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Mohsenzadeh R, Soudmand BH, Najafi A, Hazzazi F. Morphology-Driven Nanofiller Size Measurement Integrated with Micromechanical Finite Element Analysis for Quantifying Interphase in Polymer Nanocomposites. ACS APPLIED MATERIALS & INTERFACES 2024; 16:39927-39941. [PMID: 39018426 DOI: 10.1021/acsami.4c02797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2024]
Abstract
This study focused on an innovative practical method using computer vision for particle size measurement, which serves as a key precursor for predicting the elastic modulus of polymer nanocomposites. This approach involved the morphological segmentation of the nanodispersed phase. It aimed, for the first time, to address the impractical conditions resulting from the assumption of idealized single-particle sizes in a monodispersed system during modeling. Subsequently, a micromechanical finite element framework was employed to determine the interphase thickness and modulus in ultrahigh molecular weight polyethylene/nanozeolite composites, following the quantification of nanoparticle sizes. The size measurement approach relied on morphological images extracted from scanning electron microscopy micrographs of impact-fractured surfaces. To compute the interphase thickness, experimental data was fitted to an interphase-inclusive upper-bound Hashin-Shtrikman model, with the measured average particle size per composition serving as a crucial input. Subsequently, the interphase elastic modulus was computed based on its thickness, employing a hybrid modified-Hashin-Hansen and Maxwell model. These estimated interfacial variables were then utilized as inputs for the finite element model to determine the tensile modulus. A comparison between the model results and measured data revealed a maximum discrepancy of 3.29%, indicating the effectiveness of the methodology employed in quantifying interfacial properties.
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Affiliation(s)
- Rasool Mohsenzadeh
- Department of Mechanical Engineering, Technical and Vocational University (TVU), Tehran 1435761137, Iran
| | | | - Amirhossein Najafi
- Computer Engineering, K. N. Toosi University of Technology, Tehran 1969764499, Iran
| | - Fawwaz Hazzazi
- Department of Electrical Engineering, College of Engineering in Al-Kharj, Prince Sattam bin Abdulaziz University, AlKharj 11492, Saudi Arabia
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2
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Wang Z, Li F, Wang L, Liu Y, Li M, Cui N, Li C, Sun S, Hu S. A dissipative particle dynamics simulation of controlled loading and responsive release of theranostic agents from reversible crosslinked triblock copolymer vesicles. Phys Chem Chem Phys 2023; 26:304-313. [PMID: 38062783 DOI: 10.1039/d3cp04190e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
To control the transport stability and release efficiency of loaded theranostic drugs in triblock copolymer carriers, the reversible crosslinking ability is of great significance. A molecular level exploration of such a function is needed to extend existing stabilizing and responsive dissociation mechanisms of carriers. Here, dissipative particle dynamics simulations were used to first demonstrate the formation of triblock copolymer vesicular carriers. Chemical crosslinking was used to strengthen the structural stability of the vesicle shell to avoid drug leakage. Reversible decrosslinking along with dissociation of the vesicle and release of loaded drugs were then explored. The structural, energetic and dynamical properties of the system were discussed at the molecular level. The regulation mechanism of drug release patterns was revealed by systematically exploring the effect of intra and intermolecular repulsive interactions. The results indicate that the chemical crosslinking of copolymers enhanced the compactness of the vesicle shell with a strengthened microstructure, increased binding energy, and limited chain migration, thus achieving more stable delivery of drugs. In terms of drug release, we clarified how the pairwise interactions of beads in the solution system affect the responsive dissociation of the vesicle and associated release patterns (speed and amount) of drugs. More efficient delivery and smart release of theranostic drugs are achieved using such reversible crosslinked triblock copolymer vesicles.
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Affiliation(s)
- Zhikun Wang
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Fengting Li
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Li Wang
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Yueqi Liu
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Miantuo Li
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Nannan Cui
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Chunling Li
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Shuangqing Sun
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
| | - Songqing Hu
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China.
- Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China
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3
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Abdul Sattar M, Patnaik A. Molecular Insights into Antioxidant Efficiency of Melanin: A Sustainable Antioxidant for Natural Rubber Formulations. J Phys Chem B 2023; 127:8242-8256. [PMID: 37708379 DOI: 10.1021/acs.jpcb.3c03523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
N-(1,3-Dimethyl butyl)-N'-phenyl-p-phenylenediamine (6-PPD) is a worldwide antioxidant commonly added to delay the thermo-oxidative degradation of tire rubbers. Unfortunately, 6PPD and its transformation product 6PPD-quinone are toxic to aquatic organisms (e.g., coho salmon). Herein, we explore the free radical scavenging activity and protective mechanism of melanin (MLN) on natural rubber's (NR's) oxidative resistance using molecular dynamics (MD) and quantum mechanical (QM) calculations. The relationship between the molecular structure and the chemical nature of the antioxidant molecules via transition state calculations is explored to unravel the reaction mechanisms of antioxidants interacting with peroxy radicals (ROO·) of NR with the estimation of reaction barriers. Following this, the radical scavenging activity of antioxidants was quantified via a hydrogen atom transfer mechanism and bond dissociation energy calculations. Parallel MD simulations were considered to study the interfacial interactions of antioxidant molecules with polymer chains and fillers with a quantifiable structure-property correlation. Given these results, the nanocomposite (NR-MLN-SiO2) with natural antioxidant melanin manifested outstanding antioxidant properties by preferentially bagging the ROO· radicals, thus improving NR's thermal-oxidative aging relative to 6-PPD. The MD results revealed that the intermolecular interactions at the NR/antioxidant interface benefited the antioxidant MLN to bind tightly to the NR in NR-MLN-SiO2 composite, thus exhibiting improved dispersion, O2 barrier properties, and thermo-oxidative stability, which could extend the service life of NR products (e.g., tires). In addition, as a sustainable antioxidant, MLN could replace toxic antioxidants like 6-PPD. More importantly, the QM/MD simulations provided a fundamental understanding of the mechanistic pathways of antioxidant molecules in NR composites, which are conducive to designing high-performance and sustainable green elastomers.
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Affiliation(s)
- Mohammad Abdul Sattar
- Colloid and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras, Chennai600036, India
| | - Archita Patnaik
- Colloid and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras, Chennai600036, India
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4
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Hu L, Wang S, Liang L. Interface damage and fracture mechanisms of a ceramic/polymer interface based on atomic-scale simulations. Phys Chem Chem Phys 2022; 24:29461-29470. [PMID: 36468435 DOI: 10.1039/d2cp04545a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The performance of ceramic/polymer composite materials is significantly affected by their internal interfaces. To reveal the intrinsic interface fracturing mechanism of ceramic/polymer interfaces, an interfacial model composed of SiO2 and polypropylene (PP) is investigated using the molecular dynamics method. The interface damage is quantified by the increase in the interface free volume and deformation of a single PP chain. As stretching speeds increase, the free volume and outflowing atoms of PP chains decrease with the same interfacial displacement, which results in the increase of the interface strength and fracture energy. At low stretching speeds, the interface damage mechanism is determined by a competition between attractions of the PP single chains from SiO2 and PP. In contrast, at higher stretching speeds, the interface fracture is more brittle and the interface strength and fracture energy are both higher owing to the smaller cavity ratio. The results of this study contribute to an in depth understanding of the fracture mechanism of ceramic/polymer interfaces in many systems.
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Affiliation(s)
- Linhui Hu
- Beijing Key Lab of Health Monitoring and Self-Recovery for High-End Mechanical Equipment, School of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Shuai Wang
- Beijing Key Lab of Health Monitoring and Self-Recovery for High-End Mechanical Equipment, School of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Lihong Liang
- Beijing Key Lab of Health Monitoring and Self-Recovery for High-End Mechanical Equipment, School of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
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5
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Caglayan C, Kim G, Yun GJ. CNT-Reinforced Self-Healable Epoxy Dynamic Networks Based on Disulfide Bond Exchange. ACS OMEGA 2022; 7:43480-43491. [PMID: 36506194 PMCID: PMC9730311 DOI: 10.1021/acsomega.2c03910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
The design and utilization of polymers with healing capability have drawn increasing attention owing to their enhanced chain mobility and opportunity to heal minor cracks in composites. Rehealable thermoset polymers promise reduction in the maintenance cost and thus prolonged lifetime, reshaping, and recyclability. Introducing reversible covalent bonds is the mainstay strategy to achieve such plasticity in crosslinked polymers. Herein, we report a dynamic epoxy, which includes associative covalent adaptive networks (CANs) based on disulfide exchange bonds. Epoxy resin is chosen to study rehealing, as it is one of the most critical thermosetting polymers for various industries from aerospace to soft robotics. This study enlightens us about not only the consequences of CANs in the epoxy but also various factors such as soft segments and carbon nanotubes (CNTs). Epoxy dynamic networks are investigated in an attempt to explore the synergistic effect of the soft-segmented resins and CNTs on the healing and reshaping characteristics of epoxy networks along with varying stiffness. This research discusses epoxy dynamic networks in three main aspects: crosslink density, CAN density, and CNTs. Introducing soft segments into the epoxy network enhances the healing efficiency due to the increased chain mobility. A higher CAN density accelerates network rearrangement, improving the healing efficiency. It should also be noted that even with a low weight fraction of nanotubes, CNT-reinforced samples restored their initial strength more than neat samples after healing. The tensile strength of dynamic networks is at least 50 MPa, which is significant for their utility in primary or secondary structural components.
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Affiliation(s)
- Cigdem Caglayan
- Department
of Aerospace Engineering, Seoul National
University, Seoul08826, South Korea
| | - Geonwoo Kim
- Department
of Aerospace Engineering, Seoul National
University, Seoul08826, South Korea
| | - Gun Jin Yun
- Department
of Aerospace Engineering, Seoul National
University, Seoul08826, South Korea
- Institute
of Advanced Aerospace Engineering Technology, Seoul National University, Seoul08826, South Korea
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6
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Moradi M, Rezaei M. Corrosion protection mechanisms of graphene oxide-reinforced polypropylene coating for mild carbon steel by advanced molecular dynamics simulations with emphasis on resistance to water and chloride ion penetration. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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7
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Molecular Simulations and Network Analyses of Surface/Interface Effects in Epoxy Resins: How Bonding Adapts to Boundary Conditions. Polymers (Basel) 2022; 14:polym14194069. [PMID: 36236016 PMCID: PMC9573531 DOI: 10.3390/polym14194069] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
In this study, we unravel the atomic structure of a covalent resin near boundaries such as surfaces and composite constituents. For this, a molecular simulation analysis of epoxy resin hardening under various boundary conditions was performed. On the atomic level of detail, molecular dynamics simulations were employed to study crosslinking reactions and self-organization of the polymer network within nm scale slab models. The resulting structures were then coarsened into a graph theoretical description for connectivity analysis of the nodes and combined with characterization of the node-to-node vector orientation. On this basis, we show that the local bonding of epoxy resins near interfaces tends to avoid under-coordinated linker sites. For both epoxy–vacuum surface models and epoxy–silica/epoxy cellulose interfaces, we find almost fully cured polymer networks. These feature a local increase in network linking lateral to the surface/interface, rather than the dangling of unreacted epoxy groups. Consequently, interface tension is low (as compared to the work of separating bulk epoxy), and the reactivity of the resin surface appears negligible.
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Nguyen HK, Shundo A, Liang X, Yamamoto S, Tanaka K, Nakajima K. Unraveling Nanoscale Elastic and Adhesive Properties at the Nanoparticle/Epoxy Interface Using Bimodal Atomic Force Microscopy. ACS APPLIED MATERIALS & INTERFACES 2022; 14:42713-42722. [PMID: 36070235 DOI: 10.1021/acsami.2c12335] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The addition of a small fraction of solid nanoparticles to thermosetting polymers can substantially improve their fracture toughness, while maintaining various intrinsic thermomechanical properties. The underlying mechanism is largely related to the debonding process and subsequent formation of nanovoids at a nanoscale nanoparticle/epoxy interface, which is thought to be associated with a change in the structural and mechanical properties of the formed epoxy network at the interface compared with the matrix region. However, a direct characterization of the local physical properties at this nanoscale interface remains significantly challenging. Here, we employ a recently developed bimodal atomic force microscopy technique for the direct mapping of nanoscale elastic and adhesive responses of an amine-cured epoxy resin filled with ∼50 nm diameter silica nanoparticles. The obtained elastic modulus and dissipated energy maps with high spatial resolution evidence the existence of a ∼20-nm-thick interfacial epoxy layer surrounding the nanoparticles, which exhibits a reduced modulus and weaker adhesive response in comparison with the matrix properties. While the presence of such a soft and weak-adhesive interfacial layer is found not to affect the architecture of structural heterogeneities in the epoxy matrix, it conceivably supports the toughening mechanism related to the debonding and plastic nanovoid growth at the silica/epoxy interface. The incorporation of this soft interfacial layer into the Halpin-Tsai model also provides a good explanation for the effect of the silica fraction on the tensile modulus of cured epoxy nanocomposites.
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Affiliation(s)
- Hung K Nguyen
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo 152-8552, Japan
| | - Atsuomi Shundo
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
- Department of Automotive Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Xiaobin Liang
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo 152-8552, Japan
| | - Satoru Yamamoto
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Keiji Tanaka
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
| | - Ken Nakajima
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo 152-8552, Japan
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Li X, Liu J, Zheng Z. Recent progress of elastomer–silica nanocomposites toward green tires:simulation and experiment. POLYM INT 2022. [DOI: 10.1002/pi.6454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xiu Li
- Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Key Laboratory of Polymer Materials Hubei University Wuhan 430062 China
| | - Jun Liu
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials Beijing University of Chemical Technology Beijing 100029 China
| | - Zi‐Jian Zheng
- Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Key Laboratory of Polymer Materials Hubei University Wuhan 430062 China
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Liu B, Lv F, Fan X, Li Y, Jiang B. Molecular Dynamics Study of the Influence of Nano SiO2 on the Thermodynamic Properties of PMIA Composites. Polymers (Basel) 2022; 14:polym14153134. [PMID: 35956649 PMCID: PMC9370881 DOI: 10.3390/polym14153134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/25/2022] [Accepted: 07/28/2022] [Indexed: 12/04/2022] Open
Abstract
The poly-m-phenyleneisophthalamide (PMIA) is widely used in the electrical field due to its numerous favorable characteristics, but its poor thermal conductivity limits its application. In this study, PMIA was modified with nano-silica (SiO2) to improve its thermal and mechanical properties. Using iso-phthalic acid and m-phenylenediamine as monomers, the changes in the thermodynamic properties and microstructure parameters of SiO2-modified PMIA were analyzed using molecular dynamics before and after modification in the temperature range of 250~450 K. It was found that adding SiO2 improves the Young’s modulus and Shear modulus of PMIA, and the mechanical properties of PMIA, and SiO2/PMIA composites deteriorate with increasing temperature, but the mechanical properties of SiO2/PMIA composites are always better than those of pure PMIA in the temperature range of electrical equipment. Meanwhile, after doping SiO2 with the radius of 8 Å, the glass transition temperature of PMIA increases by 27.11 K, and its thermal conductivity increases from 0.249 W m−1 K−1 to 0.396 W m−1 K−1. When SiO2 is added to PMIA, the thermal expansion coefficient of PMIA will decrease in both glass and rubber states, and its thermal stability will improve. In terms of microstructure parameters, the free volume distribution of the SiO2/PMIA model is less easily dispersed than that of the PMIA model, indicating that the addition of SiO2 can improve the related properties of PMIA by hindering the movement of molecular chains.
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11
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Zhao F, Zhang H, Zhang D, Wang X, Wang D, Zhang J, Cheng J, Gao F. Molecular insights into the ‘defects’ network in the thermosets and the influence on the mechanical performance. RSC Adv 2022; 12:22342-22350. [PMID: 36105946 PMCID: PMC9364173 DOI: 10.1039/d2ra03099c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/23/2022] [Indexed: 11/26/2022] Open
Abstract
The introduction of ‘defects’ to the thermoset crosslinking network is one of the most applicable strategies for improving the modulus and toughness simultaneously. However, the reinforcement effect disappears when the ‘defects’ proportion exceeds the threshold. The speculated mechanism was that the aggregation and entanglement of the ‘defects’ chains changed the matrix topology, making the stacking structure more compact. However, the ‘defects’ are hardly directly observed in the experiment. As the result, the relationship between the ‘defects’ proportion and the package state of the matrix, and the effect on the material's mechanical performance was not explored. Herein, the network of bisphenol-A diglycidyl (DGEBA) with diethyltoluenediamine (DETDA) as the hardener was constructed using MD simulation, and n-butylamine was decorated on the matrix by replacing a proportion of DETDA acting as the ‘defects’. The results indicated that the aliphatic chains aggregated and entangled at a low concentration, occupying the voids in the rigid aromatic crosslinking structure, thus lowering the free volume. The strong non-bonding interactions drew the matrix segments close together, thus reinforcing the resin. However, the microphases formed by the aliphatic chains no longer filled the voids but created a new free volume and loosened the network when the content increased, which reduced the mechanical performance of the material. The experimental results were consistent with the findings in the simulations. The moduli of the resin increased with the increase in the n-butylamine content first and then declined. The maximum moduli of the thermosets was 3.4 GPa in S30, which was about 25% higher compared with the control; the corresponding elongation at break was 8.9%, which was about 46% improved compared with the control. The introduction of ‘defects’ to the thermoset crosslinking network is one of the most applicable strategies for improving the modulus and toughness simultaneously.![]()
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Affiliation(s)
- Fugui Zhao
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Haobo Zhang
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Dujuan Zhang
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Xiaomu Wang
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Dingxuan Wang
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Junying Zhang
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Jue Cheng
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Feng Gao
- Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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Atomistic-scale analysis of the deformation and failure of polypropylene composites reinforced by functionalized silica nanoparticles. Sci Rep 2021; 11:23108. [PMID: 34845272 PMCID: PMC8630061 DOI: 10.1038/s41598-021-02460-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/12/2021] [Indexed: 12/05/2022] Open
Abstract
Interfacial adhesion between polymer matrix and reinforcing silica nanoparticles plays an important role in strengthening polypropylene (PP) composite. To improve the adhesion strength, the surface of silica nanoparticles can be modified by grafted functional molecules. Using atomistic simulations, we examined the effect of functionalization of silica nanoparticles by hexamethyldisilazane (HMDS) and octyltriethoxysilane (OTES) molecules on the deformation and failure of silica-reinforced PP composite. We found that the ultimate tensile strength (UTS) of PP composite functionalized by OTES (28 MPa) is higher than that of HMDS (25 MPa), which is in turn higher than that passivated only by hydrogen (22 MPa). To understand the underlying mechanistic origin, we calculated the adhesive energy and interfacial strength of the interphase region, and found that both the adhesive energy and interfacial strength are the highest for the silica nanoparticles functionalized by OTES molecules, while both are the lowest by hydrogen. The ultimate failure of the polymer composite is initiated by the cavitation in the interphase region with the lowest mass density, and this cavitation failure mode is common for all the examined PP composites, but the cavitation position is dependent on the tail length of the functional molecules. The present work provides interesting insights into the deformation and cavitation failure mechanisms of the silica-reinforced PP composites, and the findings can be used as useful guidelines in selecting chemical agents for surface treatment of silica nanoparticles.
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13
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Wand CR, Gibbon S, Siperstein FR. Adsorption of Epoxy Oligomers on Iron Oxide Surfaces: The Importance of Surface Treatment and the Role of Entropy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:12409-12418. [PMID: 34644491 DOI: 10.1021/acs.langmuir.1c02015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Epoxy-based coatings are widely used in a range of industries as protective coatings. The performance of the final solid-polymer system is dependent on the physicochemical properties of the interface and the interaction between the polymer and the solid substrate. In this study, we perform atomistic molecular dynamics simulations to investigate the binding of a common component in epoxy resins, diglycidyl ether of bisphenol A (DGEBA), on two iron oxide surfaces, hematite (0001) and magnetite (100), and investigate the effect of surface hydroxylation on the binding energy. We show that adsorption of DGEBA on hematite is more favorable than on magnetite and that the adsorbed molecules are highly localized on the pristine hematite surface but mobile on highly hydroxylated hematite surfaces and magnetite surfaces irregardless of surface hydroxylation fraction. A high degree of hydroxylation significantly reduces the binding energy of DGEBA on hematite but not on magnetite. The free-energy calculations confirm the trends observed upon hydroxylation, but the magnitude of the potential of mean force is lower than the binding energy due to the entropic contributions. Therefore, it can be suggested that DGEBA will adsorb more strongly on a surface containing a higher content of hematite than magnetite and that the presence of hydroxyl groups will weaken this adsorption. The presence of hydroxyl groups increases mobility of the chains, which can affect the coating rigidity.
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Affiliation(s)
- Charlie R Wand
- Department of Chemical Engineering and Analytical Science, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Simon Gibbon
- AkzoNobel Research and Development, Northallerton, North Yorkshire DL7 7BJ, U.K
| | - Flor R Siperstein
- Department of Chemical Engineering and Analytical Science, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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14
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Li H, Zhen W, Dong C, Zhao L. Preparation of nano boron nitride-trimethylolpropane tris (3-mercaptopropionate) grafted poly (L-lactic acid) based on click chemistry and its effect on the crystallization of poly (lactic acid). REACT FUNCT POLYM 2021. [DOI: 10.1016/j.reactfunctpolym.2021.104964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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15
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Houssat M, Villeneuve-Faure C, Lahoud Dignat N, Cambronne JP. Nanoscale mechanical and electrical characterization of the interphase in polyimide/silicon nitride nanocomposites. NANOTECHNOLOGY 2021; 32:425703. [PMID: 34256368 DOI: 10.1088/1361-6528/ac13ea] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Polymer nanocomposites (pNC) have attracted wide interests in electrical insulation applications. Compared to neat matrices or microcomposites, pNC provide significant improvements in combined electrical, mechanical and thermal properties. In the understanding of the reasons behind these improvements, a major role was attributed to the interphase, the interaction zone between the nanoparticles (NP) and the matrix. Because of their nanoscale dimensions, the interphase properties are mostly theoretically described but rarely experimentally characterized. The aim of this study is to propose a nanoscale measurement protocol in order to probe mechanical (Young modulus) and electrical (dielectric permittivity) interphase features using, respectively, the peak force quantitative nanomechanical (PF-QNM) and the electrostatic force microscopy (EFM) modes of the atomic force microscopy. Measurements are performed on polyimide/silicon nitride (Si3N4) nanocomposite and the effect of a silane coupling agent treatment of Si3N4NP is considered. In order to accurately probe mechanical properties in PF-QNM mode, the impacting parameters such as the applied force, the deformation and the topography are taken into account. The interphase region has shown a higher elastic modulus compared to the matrix and a higher width (WI) value for treated NP. From EFM measurements combined to a finite element model feeded with theWIvalues obtained from PF-QNM, the interphase permittivity is determined. The corresponding values are lower than the matrix one and similar for untreated and treated NP. This is in total agreement with its higher elastic modulus and implies that the interphase is a region around the NP where the polymer chains present a better organization and thus, a restricted mobility.
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Affiliation(s)
- Mohammed Houssat
- LAPLACE, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
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16
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Sajadi SM, Vásárhelyi L, Mousavi R, Rahmati AH, Kónya Z, Kukovecz Á, Arif T, Filleter T, Vajtai R, Boul P, Pang Z, Li T, Tiwary CS, Rahman MM, Ajayan PM. Damage-tolerant 3D-printed ceramics via conformal coating. SCIENCE ADVANCES 2021; 7:7/28/eabc5028. [PMID: 34233870 PMCID: PMC8262818 DOI: 10.1126/sciadv.abc5028] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 05/24/2021] [Indexed: 12/02/2022]
Abstract
Ceramic materials, despite their high strength and modulus, are limited in many structural applications due to inherent brittleness and low toughness. Nevertheless, ceramic-based structures, in nature, overcome this limitation using bottom-up complex hierarchical assembly of hard ceramic and soft polymer, where ceramics are packaged with tiny fraction of polymers in an internalized fashion. Here, we propose a far simpler approach of entirely externalizing the soft phase via conformal polymer coating over architected ceramic structures, leading to damage tolerance. Architected structures are printed using silica-filled preceramic polymer, pyrolyzed to stabilize the ceramic scaffolds, and then dip-coated conformally with a thin, flexible epoxy polymer. The polymer-coated architected structures show multifold improvement in compressive strength and toughness while resisting catastrophic failure through a considerable delay of the damage propagation. This surface modification approach allows a simple strategy to build complex ceramic parts that are far more damage-tolerant than their traditional counterparts.
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Affiliation(s)
- Seyed Mohammad Sajadi
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA
| | - Lívia Vásárhelyi
- Interdisciplinary Excellence Centre, Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
| | | | - Amir Hossein Rahmati
- Department of Mechanical Engineering, University of Houston, Houston, TX 77204, USA
| | - Zoltán Kónya
- Interdisciplinary Excellence Centre, Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary. .,MTA-SZTE Reaction Kinetics and Surface Chemistry Research Group, University of Szeged, Szeged, Hungary
| | - Ákos Kukovecz
- Interdisciplinary Excellence Centre, Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
| | - Taib Arif
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Tobin Filleter
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Robert Vajtai
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.,Interdisciplinary Excellence Centre, Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
| | | | - Zhenqian Pang
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Teng Li
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA.
| | - Chandra Sekhar Tiwary
- Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, West Bengal, India.
| | - Muhammad M Rahman
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.
| | - Pulickel M Ajayan
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.
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17
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Molecular simulation of nano polyhedral oligomeric silsesquioxane doping effect on the properties of two-component crosslinked epoxy resin. J Mol Graph Model 2021; 107:107961. [PMID: 34119953 DOI: 10.1016/j.jmgm.2021.107961] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/26/2021] [Accepted: 06/02/2021] [Indexed: 11/21/2022]
Abstract
Epoxy resin (EP) has been extensively used in the field of insulation for its excellent electrical strength, mechanical property, chemical stability, and low cost. In this paper, computer molecular simulation is used to analyze the influence of nano-POSS (Nano-Polyhedral Oligomericsils Esquioxane) doping on the properties of epoxy composite from the micro point of view, which can provide a scientific basis for the optimization of the epoxy system. Two kinds of nano-POSS fillers with different mass fractions were doped into the base material of diglycidyl ether of bisphenol A (DGEBA) and 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecar (OSC). By molecular dynamics (MD) simulation the influence of nanofillers on the microstructure, thermal and mechanical properties of the composite were analyzed. Simulation results show that the doping of nano-POSS can improve the thermal and mechanical properties of the epoxy composite. Different nano-POSS has little effect on the glass transition temperature (Tg), coefficient of thermal expansion (CTE), and mechanical properties of the epoxy system, while the filling amount has an obvious improvement effect. Compared with EP/methyl-POSS system, the thermal and mechanical properties of the EP/phenyl-POSS system are better. At the same time, the doping of nano-POSS changed the microstructure parameters of epoxy composite. With the increase of nano-POSS filler content, fractional free volume (FFV) and mean square displacement (MSD) of both EP/POSS systems increased after the first drop. Besides, when the content of nano-POSS exceeded a certain range, the aggregation of filler itself hindered the accumulation of epoxy molecular chain segments.
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18
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Lei D, Fu YZ, Hu W, Li D, He Y, Gan LH, Gan L, Huang J. Molecular dynamics research on interfacial reinforcement between ε-CL-20 and polymeric bonding agents for humidity-insensitive solid propellant systems. JOURNAL OF POLYMER RESEARCH 2021. [DOI: 10.1007/s10965-021-02571-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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19
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Mitra A, Trifkovic M, Ponnurangam S. Surface Functionalization-Induced Effects on Nanoparticle Dispersion and Associated Changes in the Thermophysical Properties of Polymer Nanocomposites. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Anindya Mitra
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Milana Trifkovic
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Sathish Ponnurangam
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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20
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Skountzos EN, Tsalikis DG, Stephanou PS, Mavrantzas VG. Individual Contributions of Adsorbed and Free Chains to Microscopic Dynamics of Unentangled poly(ethylene Glycol)/Silica Nanocomposite Melts and the Important Role of End Groups: Theory and Simulation. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02485] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Emmanuel N. Skountzos
- Department of Chemical Engineering, University of Patras & FORTH/ICE-HT, Patras, GR 26504, Greece
| | - Dimitrios G. Tsalikis
- Department of Chemical Engineering, University of Patras & FORTH/ICE-HT, Patras, GR 26504, Greece
| | - Pavlos S. Stephanou
- Department of Chemical Engineering, Cyprus University of Technology, 30 Archbishop Kyprianou Str., 3036 Limassol, Cyprus
| | - Vlasis G. Mavrantzas
- Department of Chemical Engineering, University of Patras & FORTH/ICE-HT, Patras, GR 26504, Greece
- Particle Technology Laboratory, Department of Mechanical and Process Engineering, ETH Zürich, CH-8092 Zürich, Switzerland
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21
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Zhou M, Liu J, Hou G, Yang H, Zhang L. Study on structures, dynamics and mechanical properties of styrene butadiene rubber (SBR)/silica interfaces: A fully atomistic molecular dynamics. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123523] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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22
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Li W, Zhang L, Zhang M, Chen S. Structures of Graphene-Reinforced Epoxy Coatings and the Dynamic Diffusion of Guest Water: A Molecular Dynamics Study. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04673] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wen Li
- School of Materials Science & Engineering, Ocean University of China, Qingdao 266100, P. R. China
| | - Lei Zhang
- School of Materials Science & Engineering, Ocean University of China, Qingdao 266100, P. R. China
| | - Mutian Zhang
- School of Materials Science & Engineering, Ocean University of China, Qingdao 266100, P. R. China
| | - Shougang Chen
- School of Materials Science & Engineering, Ocean University of China, Qingdao 266100, P. R. China
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23
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Enhanced self-healing performance of graphene oxide/vitrimer nanocomposites: A molecular dynamics simulations study. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122862] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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24
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Luo Z, Yang Z, Fei Z, Su G. Investigating mechanical properties of cross-linked SiO2 and polyimide through molecular dynamics simulation. Polym Bull (Berl) 2020. [DOI: 10.1007/s00289-019-03014-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Panigrahi R, Chakraborty S, Ye J, Lim GS, Lim FCH, Yam JKH, Wu LY, Chng S, Prawirasatya M, van Herk AM, Thoniyot P. Elucidating the Role of Interfacial Hydrogen Bonds on Glass Transition Temperature Change in a Poly(Vinyl Alcohol)/SiO 2 Polymer-Nanocomposite by Noncovalent Interaction Characterization and Atomistic Molecular Dynamics Simulations. Macromol Rapid Commun 2020; 41:e2000240. [PMID: 32914462 DOI: 10.1002/marc.202000240] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/02/2020] [Indexed: 11/09/2022]
Abstract
A thorough experimental investigation of polymer-glass transition temperature (Tg ) is performed on poly(vinyl alcohol) (PVA) and fumed silica nanoparticle (SiNP) composite. This is done together with atomistic molecular dynamics simulations of PVA systems in contact with bare and fully hydroxylated silica. Experimentally, PVA-SiNP composites are prepared by simple solution casting from aqueous solutions followed by its characterization using Fourier-transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), and dynamic scanning calorimetry (DSC). Both theoretical and experimentally deduced Tg are correlated with the presence of hydrogen bonding interactions involving OH functionality present on the surface of SiNP and along PVA polymer backbone. Further deconvolution of FTIR data show that inter-molecular hydrogen bonding present between PVA and SiNP surface is directly responsible for the increase in Tg . SiNP filler and PVA matrix ratio is also optimized for a desired Tg increase. An optimal loading of SiNP exists, in order to yield the maximum Tg increase arising from the competition between hydrogen bonding and crowding effect of SiNP.
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Affiliation(s)
- Ritwik Panigrahi
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A:STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - Souvik Chakraborty
- Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A:STAR), 1 Fusionopolis Way #16-16 Connexis, 138632, Singapore
| | - Jun Ye
- Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A:STAR), 1 Fusionopolis Way #16-16 Connexis, 138632, Singapore
| | - Geraldine S Lim
- Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A:STAR), 1 Fusionopolis Way #16-16 Connexis, 138632, Singapore
| | - Freda C H Lim
- Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A:STAR), 1 Fusionopolis Way #16-16 Connexis, 138632, Singapore
| | - Joachim Khin Hun Yam
- Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A:STAR), 2 Fusionopolis Way #08-04 Innovis, 138634, Singapore
| | - Linda Yongling Wu
- Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A:STAR), 2 Fusionopolis Way #08-04 Innovis, 138634, Singapore
| | - Shuyun Chng
- Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A:STAR), 2 Fusionopolis Way #08-04 Innovis, 138634, Singapore
| | - Melissa Prawirasatya
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A:STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - Alexander M van Herk
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A:STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - Praveen Thoniyot
- Institute of Chemical and Engineering Sciences (ICES), Agency for Science, Technology and Research (A:STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
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26
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Sattar M, Patnaik A. Role of Interface Structure and Chain Dynamics on the Diverging Glass Transition Behavior of SSBR-SiO 2-PIL Elastomers. ACS OMEGA 2020; 5:21191-21202. [PMID: 32875255 PMCID: PMC7450647 DOI: 10.1021/acsomega.0c02929] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 07/28/2020] [Indexed: 05/03/2023]
Abstract
Intermolecular interactions between the constituents of a polymer nanocomposite at the polymer-particle interface strongly affect the segmental mobility of polymer chains, correlated with their glass transition behavior, and are responsible for the improved dynamical viscoelastic properties. In this work, we emphasized on the evolution of characteristic interfaces and their dynamics in silica (SiO2 NP)-reinforced, solution-polymerized, styrene butadiene rubber (SSBR) composites, whose relative prevalence varied with the phosphonium ionic liquid (PIL) volume fraction, used as an interfacial modifier. The molecular origins of such interfaces were examined through systematic dielectric spectroscopy, molecular dynamics (MD) simulations, and dynamic-mechanical analyses. The PIL facilitated H-bonding, cation-π, surface-phenyl, and van der Waals interfacial interactions between SSBR and SiO2 NP, thereby regulating the polymer chain dynamics, orientation, and mean-square displacement. Specifically, the mass density profiles from MD simulations revealed the dynamic gradient of polymer chains in the interfacial region as a function of radial distance from the center of mass of the SiO2 NP surface. The results showed a structuring effect to result in well-resolved density peaks at specific radial distances with the tangential orientation of styrene monomers in the vicinity of the SiO2 NP surface. These domino effects highlighted strong interfacial interactions to have an indispensable effect on the viscoelastic performance and thermal motion of SSBR molecular chains, leading to a higher glass transition temperature (T g) by ∼15 K, validating the experimental data. More importantly, our results gave new insights into the fundamental understanding of the fact that the strength of intermolecular interactions induced by PIL at the polymer-particle interface is the key to control the α-relaxation dynamics and T g optimization, desired for specific applications.
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Affiliation(s)
- Mohammad
Abdul Sattar
- Colloid
and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras, Chennai600036, India
- R&D
Centre, MRF Limited, MRF Road, Tiruvottiyur, Chennai 600019, India
| | - Archita Patnaik
- Colloid
and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras, Chennai600036, India
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27
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Hosseini E, Zakertabrizi M, Habibnejad Korayem A, Zaker Z, Shahsavari R. Orbital Overlapping through Induction Bonding Overcomes the Intrinsic Delamination of 3D-Printed Cementitious Binders. ACS NANO 2020; 14:9466-9477. [PMID: 32491835 DOI: 10.1021/acsnano.0c02038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
3D printing of cementitious materials holds a great promise for construction due to its rapid, consistent, modular, and geometry-controlled ability. However, its major drawback is low cohesion in the interlayer region. Herein, we report a combined experimental and computational approach to understand and control fabrication of 3D-printed cementitious materials with significantly enhanced interlayer strength using multimaterial 3D printing, in which the composition, function, and structure of the materials are programmed. Our results show that the intrinsic low interlayer cohesion is caused by excess moisture and time lag that block the majority of valuable interactions in the interlayer zone between the adjacent cement matrices. As a remedy, a thin epoxy layer is introduced as an intermediator between the adjacent extruded layers, both to improve the interlayer cohesion and to extend the possible time delay between printed adjacent layers. Our ab initio calculations demonstrate that an orbital overlap between the calcium ions, as the main electrophilic part of the cement structure, and the hydroxyl groups, as the nucleophilic part of the epoxy, create strong interfacial absorption sites. These electronic absorptions lead to several iono-covalent bonds between the cement matrix and epoxy, leading to significant improvements in tensile, shear, and compressive strengths as well as ductility of the 3D-printed composites. This is verified by our experimental data, which showed an average of 84% improvement in interlayer bonding. The upward augmentation of interlayer bonding helps 3D printing cementitious material to overcome their intrinsic limitation of weak interlayer cohesion, thereby mitigating/eliminating the key bottleneck of additive manufacturing in constructing materials.
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Affiliation(s)
- Ehsan Hosseini
- Nanomaterials Research Centre, School of Civil Engineering, Iran University of Science and Technology, Tehran 1684613114, Iran
| | - Mohammad Zakertabrizi
- Nanomaterials Research Centre, School of Civil Engineering, Iran University of Science and Technology, Tehran 1684613114, Iran
| | - Asghar Habibnejad Korayem
- Nanomaterials Research Centre, School of Civil Engineering, Iran University of Science and Technology, Tehran 1684613114, Iran
- Department of Civil Engineering, Monash University, Melbourne, VIC 3800, Australia
| | - Zafar Zaker
- Nanomaterials Research Centre, School of Civil Engineering, Iran University of Science and Technology, Tehran 1684613114, Iran
| | - Rouzbeh Shahsavari
- Department of Civil and Environmental Engineering, Rice University, Houston, Texas 77005, United States
- C-Crete Technologies LLC, Stafford, Texas 77477, United States
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28
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Effects of Different Grafting Density of Amino Silane Coupling Agents on Thermomechanical Properties of Cross-Linked Epoxy Resin. Polymers (Basel) 2020; 12:polym12081662. [PMID: 32722595 PMCID: PMC7463438 DOI: 10.3390/polym12081662] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/16/2020] [Accepted: 07/22/2020] [Indexed: 02/01/2023] Open
Abstract
In order to study the influences of amino silane coupling agents with different grafting densities on the surface of nano silica on the thermomechanical properties of cross-linked epoxy resin, the molecular dynamics method was used to establish an amorphous model and calculate the mechanical properties, glass transition temperature, mean square displacement, hydrogen bond, binding energy, and radial distribution function of the composite models in this paper. The results are as follows: with the increase of the grafting density of an amino silane coupling agent on the surface of nano silica particles, the mechanical properties and glass transition temperature of epoxy resin showed a trend of increasing first and then decreasing. When the grafting ratio was 9%, the mechanical properties and glass transition temperature of the epoxy resin were the largest, and the glass transition temperature was increased by 41 K. At the same time, it was found that the higher the grafting ratio, the lower the chain movement ability, but the higher the binding energy. Besides, the binding energy between the nanoparticles of the grafted silane coupling agent and epoxy resin was negatively correlated with the temperature. By analyzing the hydrogen bond and radial distribution function, the results showed that the improvement of the grafted silane coupling agent on the surface of the nanoparticle to the thermomechanical properties of the epoxy resin was related to the OH···O and NH···O hydrogen bonds. The analysis results indicated that the proper grafting density should be selected based on the established model size, selected nanoparticle diameter, and epoxy resin materials in order to better improve the thermomechanical properties of the epoxy resin.
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29
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Suganuma Y, Mitsuoka T, Yamamoto S, Kinjo T, Yoneyama H, Umemoto K. Wettability of Primer-Treated Al 2O 3 Surfaces by Bisphenol A Diglycidyl Ether: Determination of the Mechanism from Molecular Dynamics Simulations and Experiments. J Phys Chem B 2019; 123:4434-4442. [DOI: 10.1021/acs.jpcb.9b00680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yoshitake Suganuma
- Toyota Central R&D Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192, Japan
| | - Takuya Mitsuoka
- Toyota Central R&D Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192, Japan
| | - Satoru Yamamoto
- Dassault Systèmes K. K., 2-1-1, Osaki, Shinagawa, Tokyo 141-6020, Japan
| | - Tomoyuki Kinjo
- Toyota Central R&D Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192, Japan
| | - Hiroaki Yoneyama
- Toyota Central R&D Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192, Japan
| | - Kazuhiko Umemoto
- Toyota Central R&D Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192, Japan
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30
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Thermodynamic simulations of SrTiO3/epoxy nanocomposites with different mass fractions. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0363-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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31
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Gao J, Wang P, Wang Z, Li C, Sun S, Hu S. Self-assembly of DCPD-loaded cross-linked micelle from triblock copolymers and its pH-responsive behavior: A dissipative particle dynamics study. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2018.09.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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32
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Ghasem Zadeh Khorasani M, Silbernagl D, Platz D, Sturm H. Insights into Nano-Scale Physical and Mechanical Properties of Epoxy/Boehmite Nanocomposite Using Different AFM Modes. Polymers (Basel) 2019; 11:E235. [PMID: 30960219 PMCID: PMC6419076 DOI: 10.3390/polym11020235] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 11/16/2022] Open
Abstract
Understanding the interaction between nanoparticles and the matrix and the properties of interphase is crucial to predict the macroscopic properties of a nanocomposite system. Here, we investigate the interaction between boehmite nanoparticles (BNPs) and epoxy using different atomic force microscopy (AFM) approaches. We demonstrate benefits of using multifrequency intermodulation AFM (ImAFM) to obtain information about conservative, dissipative and van der Waals tip-surface forces and probing local properties of nanoparticles, matrix and the interphase. We utilize scanning kelvin probe microscopy (SKPM) to probe surface potential as a tool to visualize material contrast with a physical parameter, which is independent from the mechanics of the surface. Combining the information from ImAFM stiffness and SKPM surface potential results in a precise characterization of interfacial region, demonstrating that the interphase is softer than epoxy and boehmite nanoparticles. Further, we investigated the effect of boehmite nanoparticles on the bulk properties of epoxy matrix. ImAFM stiffness maps revealed the significant stiffening effect of boehmite nanoparticles on anhydride-cured epoxy matrix. The energy dissipation of epoxy matrix locally measured by ImAFM shows a considerable increase compared to that of neat epoxy. These measurements suggest a substantial alteration of epoxy structure induced by the presence of boehmite.
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Affiliation(s)
- Media Ghasem Zadeh Khorasani
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
- Department Polymertechnik/Polymerphysik, Technical University of Berlin, D-10587 Berlin, Germany.
| | - Dorothee Silbernagl
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
| | - Daniel Platz
- TU Wien, Institute of Sensor and Actuator Systems, A-1040 Vienna, Austria.
| | - Heinz Sturm
- Bundesanstalt für Materialforschung und -prüfung (BAM), Div. 6.6, D-12205 Berlin, Germany.
- Department Mechanical Engineering and Transport Systems, Technical University of Berlin, D-10587 Berlin, Germany.
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33
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Xu J, Zhang J, Xiong D, Lin W, Wen L, Zhang L. Enhanced stability of crosslinked and charged unimolecular micelles from multigeometry triblock copolymers with short hydrophilic segments: dissipative particle dynamics simulation. SOFT MATTER 2019; 15:546-558. [PMID: 30644512 DOI: 10.1039/c8sm01941j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
High micellar stability and well-performed drug loading and release are two conflicting factors for unimolecular micelles as an ideal drug delivery system. Achieving the formation of unimolecular micelles with short hydrophilic blocks is a challenging and promising approach to solve this bottleneck and limitation of current unimolecular micelle systems. In this work, dissipative particle dynamics (DPD) simulation is used to study the synergetic effect of crosslinking and electrostatic repulsion on stability of unimolecular micelles and to analyze the micro-mechanism and factors influencing this synergetic stabilization strategy. The strategy can generate unimolecular micelles with extremely high stability for various supramolecular polymers with short hydrophilic chains. Protonation of DEAEMA blocks leads to a large improvement in micellar hydrophilicity. The protonated middle layer further shrinks through crosslinking to produce the largest charge density, enlarging the electrostatic repulsion between colloidal particles. Additionally, the crosslinking and protonation treatment maximizes the extension degree of hydrophilic EO segments due to the increasing steric hindrance and poor compatibility between DEAHEMA and EO blocks. In this study, the relation between shrinkage degree of hydrophobic cores and stability of unimolecular micelles is first reported. The above-mentioned transition of micellar structures and properties results in the maximum degree of core shrinkage (Rg of MMA blocks) corresponding to the high stability of unimolecular micelles. Further study shows that the increasing cyclization degree, the mode of end cyclization, and the crosslinking and electrostatic repulsion of the middle layer all exert favorable effects on the stability of unimolecular micelles due to controlled shrinkage of hydrophobic cores.
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Affiliation(s)
- Jianchang Xu
- Guangdong Provincial Key Lab of Green Chemical Product Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Jing Zhang
- Guangdong Provincial Key Lab of Green Chemical Product Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Di Xiong
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China
| | - Wenjing Lin
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
| | - Liyang Wen
- Guangdong Provincial Key Lab of Green Chemical Product Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Lijuan Zhang
- Guangdong Provincial Key Lab of Green Chemical Product Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
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Tang Y, Tang C, Hu D, Gui Y. Effect of Aminosilane Coupling Agents with Different Chain Lengths on Thermo-Mechanical Properties of Cross-Linked Epoxy Resin. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 8:E951. [PMID: 30463219 PMCID: PMC6266079 DOI: 10.3390/nano8110951] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/08/2018] [Accepted: 11/11/2018] [Indexed: 11/22/2022]
Abstract
In this paper, a molecular dynamics simulation method was used to study the thermo-mechanical properties of cross-linked epoxy resins doped with nano silica particles that were grafted with 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and 3-[2-(2-aminoethylamino)ethylamino]-propyl-trimethoxysilane with different chain lengths. Firstly, a set of pure epoxy resin models, and four sets of SiO₂/EP composite models were established. Then, a reasonable structure was obtained through a series of optimizations using molecular dynamics calculations. Next, the mechanical properties, hydrogen bond statistics, glass transition temperature, free volume fraction, and chain spacing of the five models were studied comparatively. The results show that doped nano silica particles of surfaces grafted with 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and 3-[2-(2-aminoethylamino)ethylamino]-propyl-trimethoxysilane with different chain lengths enhanced mechanical properties such as elastic modulus, shear modulus, and volume modulus obviously. The glass transition temperature increased by 15⁻16 K, 40⁻41 K, and 24⁻27 K, respectively. Finally, the data show that the cross-linked epoxy resin modified by nanoparticles grafted with N-(2-aminoethyl)-3-aminopropyl trimethoxysilane had better effects for improving thermo-mechanical properties by the comparatively studying the five groups of parameter models under the same conditions.
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Affiliation(s)
- Yujing Tang
- College of Engineering and Technology, Southwest University, Chongqing 400715, China.
| | - Chao Tang
- College of Engineering and Technology, Southwest University, Chongqing 400715, China.
| | - Dong Hu
- College of Engineering and Technology, Southwest University, Chongqing 400715, China.
| | - Yingang Gui
- College of Engineering and Technology, Southwest University, Chongqing 400715, China.
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35
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Guo L, Safi ZS, Kaya S, Shi W, Tüzün B, Altunay N, Kaya C. Anticorrosive Effects of Some Thiophene Derivatives Against the Corrosion of Iron: A Computational Study. Front Chem 2018; 6:155. [PMID: 29868558 PMCID: PMC5949371 DOI: 10.3389/fchem.2018.00155] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 04/19/2018] [Indexed: 11/13/2022] Open
Abstract
It is known that iron is one of the most widely used metals in industrial production. In this work, the inhibition performances of three thiophene derivatives on the corrosion of iron were investigated in the light of several theoretical approaches. In the section including DFT calculations, several global reactivity descriptors such as EHOMO, ELUMO, ionization energy (I), electron affinity (A), HOMO-LUMO energy gap (ΔE), chemical hardness (η), softness (σ), as well as local reactivity descriptors like Fukui indices, local softness, and local electrophilicity were considered and discussed. The adsorption behaviors of considered thiophene derivatives on Fe(110) surface were investigated using molecular dynamics simulation approach. To determine the most active corrosion inhibitor among studied thiophene derivatives, we used the principle component analysis (PCA) and agglomerative hierarchical cluster analysis (AHCA). Accordingly, all data obtained using various theoretical calculation techniques are consistent with experiments.
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Affiliation(s)
- Lei Guo
- School of Material and Chemical Engieering, Tongren University, Tongren, China
| | - Zaki S Safi
- Chemistry Department, Faculty of Science, Al Azhar University-Gaza, Gaza City, Palestine
| | - Savas Kaya
- Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas, Turkey
| | - Wei Shi
- School of Material and Chemical Engieering, Tongren University, Tongren, China
| | - Burak Tüzün
- Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas, Turkey
| | - Nail Altunay
- Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas, Turkey
| | - Cemal Kaya
- Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas, Turkey
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36
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Origin of Modulus Improvement for Epoxide-terminated Hyperbranched Poly(ether sulphone)/DGEBA/TETA Systems. CHINESE JOURNAL OF POLYMER SCIENCE 2018. [DOI: 10.1007/s10118-018-2114-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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37
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Zheng Z, Li F, Liu J, Pastore R, Raos G, Wu Y, Zhang L. Effects of chemically heterogeneous nanoparticles on polymer dynamics: insights from molecular dynamics simulations. SOFT MATTER 2018; 14:1219-1226. [PMID: 29350725 DOI: 10.1039/c7sm02414b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The dispersion of solid nanoparticles within polymeric materials is widely used to enhance their performance. Many scientific and technological aspects of the resulting polymer nanocomposites have been studied, but the role of the structural and chemical heterogeneity of the nanoparticles has just started to be appreciated. For example, simulations of polymer films on planar heterogeneous surfaces revealed unexpected, non-monotonic activation energy to diffusion on varying the surface composition. Motivated by these intriguing results, here we simulate via molecular dynamics a different, fully three-dimensional system, in which the heterogeneous nanoparticles are incorporated in a polymer melt. The nanoparticles are roughly spherical assemblies of strongly and weakly attractive sites, in fractions of f and 1 - f, respectively. We show that the polymer diffusion is still characterized by a non-monotonic dependence of the activation energy on f. The comparison with the case of homogeneous nanoparticles clarifies that the effect of the heterogeneity increases on approaching the polymer glass transition.
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Affiliation(s)
- Zijian Zheng
- Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 100029 Beijing, China.
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38
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Zhao J, Wu L, Zhan C, Shao Q, Guo Z, Zhang L. Overview of polymer nanocomposites: Computer simulation understanding of physical properties. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.10.035] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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39
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Molecular dynamics simulation of the glass transition temperature of fullerene filled cis-1,4-polybutadiene nanocomposites. CHINESE JOURNAL OF POLYMER SCIENCE 2017. [DOI: 10.1007/s10118-018-2015-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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40
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Computational Thermomechanical Properties of Silica⁻Epoxy Nanocomposites by Molecular Dynamic Simulation. Polymers (Basel) 2017; 9:polym9090430. [PMID: 30965735 PMCID: PMC6418791 DOI: 10.3390/polym9090430] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/31/2017] [Accepted: 09/04/2017] [Indexed: 11/16/2022] Open
Abstract
Silica⁻epoxy nanocomposite models were established to investigate the influence of silane coupling agent on the structure and thermomechanical properties of the nanocomposites through molecular dynamics simulation. Results revealed that incorporating silica nanoparticles into a polymer matrix could improve thermomechanical properties of the composites and increase their glass transition temperature and thermal conductivity. Their thermomechanical properties were further enhanced through silane coupling agent modification on the surface of fillers. Compared with that of pure epoxy, the glass transition temperatures of the silica⁻epoxy composites with grafting ratios of 5% and 10% increased by 17 and 28 K, respectively. The thermal conductivities of the two models at room temperature respectively increased by 60.0% and 67.1%. At higher temperature 450 K, thermal conductivity of the nanocomposite model with a high grafting ratio of 10% demonstrated a considerable increase of approximately 50% over the pure epoxy resin (EP) model. The elastic and shear modulus of the nanocomposite models decreased at temperatures below their glass transition temperatures. These observations were further addressed in the interpretation from three aspects: segmental mobility capability, radial distribution function, and free volume fraction. Our computational results are largely consistent with existing experimental data, and our simulation model got fully validated.
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41
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Wang Z, Gao J, Ustach V, Li C, Sun S, Hu S, Faller R. Tunable Permeability of Cross-Linked Microcapsules from pH-Responsive Amphiphilic Diblock Copolymers: A Dissipative Particle Dynamics Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7288-7297. [PMID: 28661159 DOI: 10.1021/acs.langmuir.7b01586] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Using dissipative particle dynamics simulation, we probe the tunable permeability of cross-linked microcapsules made from pH-sensitive diblock copolymers poly(ethylene oxide)-b-poly(N,N-diethylamino-2-ethyl methacrylate) (PEO-b-PDEAEMA). We first examine the self-assembly of non-cross-linked microcapsules and their pH-responsive collapse and then explore the effects of cross-linking and block interaction on the swelling or deswelling of cross-linked microcapsules. Our results reveal a preferential loading of hydrophobic dicyclopentadiene (DCPD) molecules in PEO-b-PDEAEMA copolymers. Upon reduction of pH, non-cross-linked microcapsules fully decompose into small wormlike clusters as a result of large self-repulsions of protonated copolymers. With increasing degree of cross-linking, the morphology of the microcapsule becomes more stable to pH change. The highly cross-linked microcapsule shell undergoes significant local polymer rearrangement in acidic solution, which eliminates the amphiphilicility and therefore enlarges the permeability of the shell. The responsive cross-linked shell experiences a disperse-to-buckle configurational transition upon reduction of pH, which is effective for the steady or pulsatile regulation of shell permeability. The swelling rate of the cross-linked shell is dependent on both electrostatic and nonelectrostatic interactions between the pH-sensitive groups as well as the other groups. Our study highlights the combination of cross-linking structure and block interactions in stabilizing microcapsules and tuning their selective permeability.
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Affiliation(s)
- Zhikun Wang
- Department of Chemical Engineering, University of California , Davis, California 95616, United States
| | | | - Vincent Ustach
- Department of Chemical Engineering, University of California , Davis, California 95616, United States
| | | | | | | | - Roland Faller
- Department of Chemical Engineering, University of California , Davis, California 95616, United States
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42
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Perchacz M, Donato RK, Seixas L, Zhigunov A, Konefał R, Serkis-Rodzeń M, Beneš H. Ionic Liquid-Silica Precursors via Solvent-Free Sol-Gel Process and Their Application in Epoxy-Amine Network: A Theoretical/Experimental Study. ACS APPLIED MATERIALS & INTERFACES 2017; 9:16474-16487. [PMID: 28443326 DOI: 10.1021/acsami.7b02631] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
This work describes the solvent-free sol-gel synthesis of epoxy-functionalized silica-based precursors in the presence of 1-butyl-3-methylimidazolium-based ionic liquids (ILs) containing different anions: chloride (Cl-) and methanesulfonate (MeSO3-). The IL-driven sol-gel mechanisms were investigated in detail using experimental characterizations (29Si NMR and ATR FTIR spectroscopy) and a theoretical computational method based on density functional theory (DFT). We observed complex IL influence on both hydrolysis and condensation steps, involving especially H-bonding and Coulomb coupling stabilization of the process intermediates. The obtained IL-silica precursors and their further xerogels were widely characterized (rheology measurements, MALDI TOF, 29Si NMR, ATR FTIR, and DFT simulation), which allowed observation of their precise silica structures and established their most energetically favorable conformations. The detected silica structures were dependent on the IL type and varied from highly condensed 3D cage-like to branched ladder-like and cyclic ones. The application of prepared IL-silica precursors as reinforcing additives into the epoxy-amine network led to an improvement in the organic/inorganic interphase interactions through chemical and physical bonding. Uniform and well-dispersed silica aggregates, in the size of ∼30 nm, were formed when ≤6.8 wt % of each IL-silica precursor was applied into the epoxy-amine network. The use of imidazolium-based ILs contributed to a significant improvement in thermomechanical properties of hybrids and reduced their UV absorption ability compared to that of the reference matrix. All hybrids exhibited an increase in energy to break (up to ∼53%), elongation at break (up to ∼43%), shear storage modulus in the rubbery region (up to 4 times), and thermo-oxidative stability.
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Affiliation(s)
- Magdalena Perchacz
- Institute of Macromolecular Chemistry AS CR , v.v.i., Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
| | - Ricardo Keitel Donato
- MackGraphe-Graphene and Nanomaterials Research Center, Mackenzie Presbyterian University , Rua da Consolação 896, São Paulo 01302-907, SP Brazil
| | - Leandro Seixas
- MackGraphe-Graphene and Nanomaterials Research Center, Mackenzie Presbyterian University , Rua da Consolação 896, São Paulo 01302-907, SP Brazil
| | - Alexander Zhigunov
- Institute of Macromolecular Chemistry AS CR , v.v.i., Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
| | - Rafał Konefał
- Institute of Macromolecular Chemistry AS CR , v.v.i., Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
| | - Magdalena Serkis-Rodzeń
- Institute of Macromolecular Chemistry AS CR , v.v.i., Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
| | - Hynek Beneš
- Institute of Macromolecular Chemistry AS CR , v.v.i., Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic
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43
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Demir B, Henderson LC, Walsh TR. Design Rules for Enhanced Interfacial Shear Response in Functionalized Carbon Fiber Epoxy Composites. ACS APPLIED MATERIALS & INTERFACES 2017; 9:11846-11857. [PMID: 28317383 DOI: 10.1021/acsami.6b16041] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Carbon-fiber reinforced composites are ideal light-weighting candidates to replace traditional engineering materials. The mechanical performance of these composites results from a complex interplay of influences operating over several length and time scales. The mechanical performance may therefore be limited by many factors, one of which being the modest interfacial adhesion between the carbon fiber and the polymer. Chemical modification of the fiber, via surface grafting of molecules, is one possible strategy to enhance interactions across the fiber-polymer interface. To achieve systematic improvements in these modified materials, the ability to manipulate and monitor the molecular structure of the polymer interphase and the surface grafted molecules in the composite is essential, but challenging to accomplish from a purely experimental perspective. Alternatively, molecular simulations can bridge this knowledge gap by providing molecular-scale insights into the optimal design of these surface-grafted molecules to deliver superior mechanical properties. Here we use molecular dynamics simulations to predict the interfacial shear response of a typical epoxy/carbon-fiber composite for both pristine fiber and a range of surface graftings. We allow for the dynamic curing of the epoxy in the presence of the functionalized surface, including cross-link formation between the grafted molecules and the polymer matrix. Our predictions agree with recently reported experimental data for these systems and reveal the molecular-scale origins of the enhanced interfacial shear response arising from functionalization. In addition to the presence of interfacial covalent bonds, we find that the interfacial structural complexity, resulting from the presence of the grafted molecules, and a concomitant spatial homogeneity of the interphase polymer density are beneficial factors in conferring high interfacial shear stress. Our approach paves the way for computational screening processes to design, test, and rapidly identify viable surface modifications in silico, which would enable rapid systematic progress in optimizing the match between the carbon fiber treatment and the desired thermoset polymer matrix.
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Affiliation(s)
- Baris Demir
- Institute for Frontier Materials, Deakin University , Geelong, Victoria 3216, Australia
| | - Luke C Henderson
- Institute for Frontier Materials, Deakin University , Geelong, Victoria 3216, Australia
| | - Tiffany R Walsh
- Institute for Frontier Materials, Deakin University , Geelong, Victoria 3216, Australia
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44
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Mun S, Bowman AL, Nouranian S, Gwaltney SR, Baskes MI, Horstemeyer MF. Interatomic Potential for Hydrocarbons on the Basis of the Modified Embedded-Atom Method with Bond Order (MEAM-BO). J Phys Chem A 2017; 121:1502-1524. [DOI: 10.1021/acs.jpca.6b11343] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sungkwang Mun
- Center for Advanced
Vehicular Systems (CAVS), Mississippi State University, Mississippi
State, Mississippi 39762, United States
| | - Andrew L. Bowman
- Center for Advanced
Vehicular Systems (CAVS), Mississippi State University, Mississippi
State, Mississippi 39762, United States
| | - Sasan Nouranian
- Department of Chemical Engineering, The University of Mississippi, University, Mississippi 38677, United States
| | - Steven R. Gwaltney
- Department
of Chemistry, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Michael I. Baskes
- Department of Aerospace Engineering, Mississippi State University, Mississippi State, Mississippi 39762, United States
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Department
of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, United States
- Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203, United States
| | - Mark F. Horstemeyer
- Center for Advanced
Vehicular Systems (CAVS), Mississippi State University, Mississippi
State, Mississippi 39762, United States
- Department
of Mechanical Engineering, Mississippi State University, Mississippi State, Mississippi 39762, United States
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45
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Huang H, Dobryden I, Ihrner N, Johansson M, Ma H, Pan J, Claesson PM. Temperature-dependent surface nanomechanical properties of a thermoplastic nanocomposite. J Colloid Interface Sci 2017; 494:204-214. [PMID: 28160705 DOI: 10.1016/j.jcis.2017.01.096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/24/2017] [Accepted: 01/24/2017] [Indexed: 11/26/2022]
Abstract
In polymer nanocomposites, particle-polymer interactions influence the properties of the matrix polymer next to the particle surface, providing different physicochemical properties than in the bulk matrix. This region is often referred to as the interphase, but detailed characterization of its properties remains a challenge. Here we employ two atomic force microscopy (AFM) force methods, differing by a factor of about 15 in probing rate, to directly measure the surface nanomechanical properties of the transition region between filler particle and matrix over a controlled temperature range. The nanocomposite consists of poly(ethyl methacrylate) (PEMA) and poly(isobutyl methacrylate) (PiBMA) with a high concentration of hydrophobized silica nanoparticles. Both AFM methods demonstrate that the interphase region around a 40-nm-sized particle located on the surface of the nanocomposite could extend to 55-70nm, and the interphase exhibits a gradient distribution in surface nanomechanical properties. However, the slower probing rate provides somewhat lower numerical values for the surface stiffness. The analysis of the local glass transition temperature (Tg) of the interphase and the polymer matrix provides evidence for reduced stiffness of the polymer matrix at high particle concentration, a feature that we attribute to selective adsorption. These findings provide new insight into understanding the microstructure and mechanical properties of nanocomposites, which is of importance for designing nanomaterials.
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Affiliation(s)
- Hui Huang
- Key Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China; KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden.
| | - Illia Dobryden
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden
| | - Niklas Ihrner
- KTH Royal Institute of Technology, Department of Fiber and Polymer Technology, Teknikringen 56-58, SE-10044 Stockholm, Sweden
| | - Mats Johansson
- KTH Royal Institute of Technology, Department of Fiber and Polymer Technology, Teknikringen 56-58, SE-10044 Stockholm, Sweden
| | - Houyi Ma
- Key Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Jinshan Pan
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden
| | - Per M Claesson
- KTH Royal Institute of Technology, School of Chemical Sciences and Engineering, Department of Chemistry, Surface and Corrosion Science, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden; SP Technical Research Institute of Sweden, SP Chemistry, Materials and Surfaces, Box 5607, SE-11486 Stockholm, Sweden.
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46
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Gao L, Zhang Q, Li H, Yu S, Zhong W, Sui G, Yang X. Effect of epoxy monomer structure on the curing process and thermo-mechanical characteristics of tri-functional epoxy/amine systems: a methodology combining atomistic molecular simulation with experimental analyses. Polym Chem 2017. [DOI: 10.1039/c7py00063d] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A methodology, which combined molecular simulation with experimental research, was established to expound the performance of a tri-functional epoxy/amine system.
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Affiliation(s)
- Liang Gao
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Qingjie Zhang
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Hao Li
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Siruo Yu
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Weihong Zhong
- School of Mechanical and Materials Engineering
- Washington State University
- Pullman
- USA
| | - Gang Sui
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Xiaoping Yang
- State Key Laboratory of Organic–Inorganic Composites
- College of Materials Science and Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
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47
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Guo L, Qi C, Zheng X, Zhang R, Shen X, Kaya S. Toward understanding the adsorption mechanism of large size organic corrosion inhibitors on an Fe(110) surface using the DFTB method. RSC Adv 2017. [DOI: 10.1039/c7ra04120a] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Compared with the conventional DFT approach, SCC-DFTB method is more effective to deal with the adsorption issues of large size organic corrosion inhibitors on metal surface.
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Affiliation(s)
- Lei Guo
- College of Material and Chemical Engineering
- Tongren University
- Tongren 554300
- China
| | - Chengwei Qi
- School of Petroleum Engineering
- Chongqing University of Science and Technology
- Chongqing 401331
- China
| | - Xingwen Zheng
- Material Corrosion and Protection Key Laboratory of Sichuan Province
- Zigong 643000
- China
| | - Renhui Zhang
- College of Material and Chemical Engineering
- Tongren University
- Tongren 554300
- China
| | - Xun Shen
- College of Material and Chemical Engineering
- Tongren University
- Tongren 554300
- China
| | - Savaş Kaya
- Cumhuriyet University
- Faculty of Science
- Department of Chemistry
- Sivas 58140
- Turkey
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