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Zhong J, Wen Z, Wu Y, Luo H, Liu G, Hu J, Song H, Wang T, Liang X, Zhou H, Huang W, Zhou H. A Bioinspired Design of Protective Al 2O 3/Polyurethane Hierarchical Composite Film Through Layer-By-Layer Deposition. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2402940. [PMID: 38767181 PMCID: PMC11267295 DOI: 10.1002/advs.202402940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/10/2024] [Indexed: 05/22/2024]
Abstract
Structural materials such as ceramics, metals, and carbon fiber-reinforced plastics (CFRP) are frequently threatened by large compressive and impact forces. Energy absorption layers, i.e., polyurethane and silicone foams with excellent damping properties, are applied on the surfaces of different substrates to absorb energy. However, the amount of energy dissipation and penetration resistance are limited in commercial polyurethane foams. Herein, a distinctive nacre-like architecture design strategy is proposed by integrating hard porous ceramic frameworks and flexible polyurethane buffers to improve energy absorption and impact resistance. Experimental investigations reveal the bioinspired designs exhibit optimized hardness, strength, and modulus compared to that of polyurethane. Due to the multiscale energy dissipation mechanisms, the resulting normalized absorbed energy (≈8.557 MJ m-3) is ≈20 times higher than polyurethane foams under 50% quasi-static compression. The bioinspired composites provide superior protection for structural materials (CFRP, glass, and steel), surpassing polyurethane films under impact loadings. It is shown CFRP coated with the designed materials can withstand more than ten impact loadings (in energy of 10 J) without obvious damage, which otherwise delaminates after a single impact. This biomimetic design strategy holds the potential to offer valuable insights for the development of lightweight, energy-absorbent, and impact-resistant materials.
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Affiliation(s)
- Jiaming Zhong
- State Key Laboratory of Materials Processing and Die and Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China
| | - Zhixiong Wen
- State Key Laboratory of Materials Processing and Die and Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China
| | - Yibo Wu
- Luoyang Ship Material Research InstituteLuoyang471023China
| | - Hao Luo
- Luoyang Ship Material Research InstituteLuoyang471023China
| | - Guodong Liu
- Luoyang Ship Material Research InstituteLuoyang471023China
| | - Jianqiao Hu
- LNMInstitute of MechanicsChinese Academy of SciencesBeijing100190China
| | - Hengxu Song
- LNMInstitute of MechanicsChinese Academy of SciencesBeijing100190China
- School of Engineering ScienceUniversity of Chinese Academy of SciencesBeijing100049China
| | - Tao Wang
- National Key Laboratory of Explosion Science and Safety ProtectionBeijing Institute of TechnologyBeijing100081China
| | - Xudong Liang
- School of ScienceHarbin Institute of Technology (Shenzhen)Shenzhen518055China
| | - Helezi Zhou
- State Key Laboratory of Materials Processing and Die and Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China
| | - Wei Huang
- State Key Laboratory of Materials Processing and Die and Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China
| | - Huamin Zhou
- State Key Laboratory of Materials Processing and Die and Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China
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Mansourian-Tabaei M, Majdoub M, Sengottuvelu D, Stoddard DL, Thirumalai RVKG, Ucak-Astarlioglu MG, Al-Ostaz A, Nouranian S. Polyurea/Aminopropyl Isobutyl Polyhedral Oligomeric Silsesquioxane-Functionalized Graphene Nanoplatelet Nanocomposites for Force Protection Applications. ACS APPLIED MATERIALS & INTERFACES 2024; 16:19625-19641. [PMID: 38588400 DOI: 10.1021/acsami.4c02244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Herein, the development of new nanocomposite systems is reported based on one-part polyurea (PU) and aminopropyl isobutyl polyhedral oligomeric silsesquioxane (POSS)-functionalized graphene nanoplatelets (GNP-POSS) as compatible nanoreinforcements with the PU resin. GNP-POSS was effectively synthesized via a two-step synthesis protocol, including ultrasonication-assisted reaction and precipitation, and carefully characterized with respect to its chemical and crystalline structure, morphology, and thermal stability. FTIR and XPS spectroscopy analyses revealed that POSS interacts with the residual oxygen moieties of the GNPs through both covalent and noncovalent bonding. The X-ray diffraction pattern of GNP-POSS further revealed that the crystallinity of the GNPs was not altered after their functionalization with POSS. GNP-POSS was successfully incorporated in PU at contents of 1, 3, 5, and 10 wt % to yield PU/GNP-POSS nanocomposite films. An ATR-FTIR analysis of these films confirmed the presence of strong interfacial interactions between the urea groups of PU and the GNP-POSS functionalities. Moreover, the PU/GNP-POSS nanocomposite films exhibited enhanced thermal stability and mechanical properties compared to those of the neat PU film. The quasi-static tensile testing of the PU/GNP-POSS samples revealed remarkable enhancements in the tensile strength (from 7.9 for the neat PU to 25.1 MPa for PU/GNP-POSS) and Young's modulus (238-617 MPa), while elongation at break and toughness also showed 14 and 125% improvements, respectively. Finally, the effects of GNP-POSS content on the morphological, quasistatic tensile, and high-strain-rate dynamic behavior of the PU/GNP-POSS nanocomposite films were also investigated. Overall, the tests performed using a split-Hopkinson pressure bar setup revealed a large increase in the film strength (from 147.6 for the neat PU film to 199 MPa for the PU/GNP-POSS film) and a marginal increase in the energy density of the film (38.1-40.8 kJ/m3). These findings support the suitability of the PU/GNP-POSS nanocomposite films for force protection applications.
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Affiliation(s)
- Mohammad Mansourian-Tabaei
- Department of Chemical Engineering, University of Mississippi, University, Mississippi 38677, United States
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
| | - Mohammed Majdoub
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
| | - Dineshkumar Sengottuvelu
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
| | - Damian L Stoddard
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
- Department of Mechanical Engineering, University of Mississippi, University, Mississippi 38677, United States
| | - Rooban V K G Thirumalai
- Institute for Imaging and Analytical Technologies, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Mine G Ucak-Astarlioglu
- Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, Mississippi 39180-6199, United States
| | - Ahmed Al-Ostaz
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
- Department of Civil Engineering, University of Mississippi, University, Mississippi 38677, United States
| | - Sasan Nouranian
- Department of Chemical Engineering, University of Mississippi, University, Mississippi 38677, United States
- Center for Graphene Research and Innovation, University of Mississippi, University, Mississippi 38677, United States
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Zheng L, Xie Q, Hu G, Wang B, Song D, Zhang Y, Liu Y. Synthesis, Structure and Properties of Polyester Polyureas via a Non-Isocyanate Route with Good Combined Properties. Polymers (Basel) 2024; 16:993. [PMID: 38611251 PMCID: PMC11014397 DOI: 10.3390/polym16070993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
Polyureas have been widely applied in many fields, such as coatings, fibers, foams and dielectric materials. Traditionally, polyureas are prepared from isocyanates, which are highly toxic and harmful to humans and the environment. Synthesis of polyureas via non-isocyanate routes is green, environmentally friendly and sustainable. However, the application of non-isocyanate polyureas is quite restrained due to their brittleness as the result of the lack of a soft segment in their molecular blocks. To address this issue, we have prepared polyester polyureas via an isocyanate-free route and introduced polyester-based soft segments to improve their toughness and endow high impact resistance to the polyureas. In this paper, the soft segments of polyureas were synthesized by the esterification and polycondensation of dodecanedioic acid and 1,4-butanediol. Hard segments of polyureas were synthesized by melt polycondensation of urea and 1,10-diaminodecane without a catalyst or high pressure. A series of polyester polyureas were synthesized by the polycondensation of the soft and hard segments. These synthesized polyester-type polyureas exhibit excellent mechanical and thermal properties. Therefore, they have high potential to substitute traditional polyureas.
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Affiliation(s)
- Liuchun Zheng
- School of Chemical Engineering and Technology, Xinjiang University, Urumqi 830017, China
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
- Cangzhou Insititute of Tiangong University, Cangzhou 061000, China
| | - Qiqi Xie
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
| | - Guangjun Hu
- Shenghong Advanced Materials Research Institute, Shanghai 201403, China
| | - Bing Wang
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
| | - Danqing Song
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
| | - Yunchuan Zhang
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
| | - Yi Liu
- School of Chemical Engineering and Technology, State Key Laboratory of Separation Membranes and Membrane Processes, Education Ministry Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes, Tiangong University, Tianjin 300387, China
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Toader G, Diacon A, Axinte SM, Mocanu A, Rusen E. State-of-the-Art Polyurea Coatings: Synthesis Aspects, Structure-Properties Relationship, and Nanocomposites for Ballistic Protection Applications. Polymers (Basel) 2024; 16:454. [PMID: 38399832 PMCID: PMC10893384 DOI: 10.3390/polym16040454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 02/25/2024] Open
Abstract
This review presents polyurea (PU) synthesis, the structure-properties relationship, and characterization aspects for ballistic protection applications. The synthesis of polyurea entails step-growth polymerization through the reaction of an isocyanate monomer/prepolymer and a polyamine, each component possessing a functionality of at least two. A wide range of excellent properties such as durability and high resistance against atmospheric, chemical, and biological factors has made this polymer an outstanding option for ballistic applications. Polyureas are an extraordinary case because they contain both rigid segments, which are due to the diisocyanates used and the hydrogen points formed, and a flexible zone, which is due to the chemical structure of the polyamines. These characteristics motivate their application in ballistic protection systems. Polyurea-based coatings have also demonstrated their abilities as candidates for impulsive loading applications, affording a better response of the nanocomposite-coated metal sheet at the action of a shock wave or at the impact of a projectile, by suffering lower deformations than neat metallic plates.
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Affiliation(s)
- Gabriela Toader
- Military Technical Academy “Ferdinand I”, 39-49 George Coșbuc Boulevard, 050141 Bucharest, Romania; (G.T.); (A.D.)
| | - Aurel Diacon
- Military Technical Academy “Ferdinand I”, 39-49 George Coșbuc Boulevard, 050141 Bucharest, Romania; (G.T.); (A.D.)
- Faculty of Chemical Engineering and Biotechnologies, University Politehnica Bucharest, Gh. Polizu Street, 011061 Bucharest, Romania;
| | - Sorin Mircea Axinte
- S.C. Daily Sourcing & Research SRL, 95-97 Calea Griviței, 010705 Bucharest, Romania;
| | - Alexandra Mocanu
- Faculty of Chemical Engineering and Biotechnologies, University Politehnica Bucharest, Gh. Polizu Street, 011061 Bucharest, Romania;
- National Institute for Research and Development in Microtechnologies—IMT Bucharest, 126A Erou Iancu Nicolae Street, 077190 Bucharest, Romania
| | - Edina Rusen
- Faculty of Chemical Engineering and Biotechnologies, University Politehnica Bucharest, Gh. Polizu Street, 011061 Bucharest, Romania;
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Wang Y, Ding L, Lin J, Qiu X, Wu C, Liu C, Tian Y, Zhang R, Huang W, Ma M. Recent Developments in Polyurea Research for Enhanced Impact Penetration Resistance and Blast Mitigation. Polymers (Basel) 2024; 16:440. [PMID: 38337329 DOI: 10.3390/polym16030440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024] Open
Abstract
Polyurea has gained significant attention in recent years as a functional polymer material, specifically regarding blast and impact protection. The molecular structure of polyurea is characterized by the rapid reaction between isocyanate and the terminal amine component, and forms an elastomeric copolymer that enhances substrate protection against blast impact and fragmentation penetration. At the nanoscale, a phase-separated microstructure emerges, with dispersed hard segment microregions within a continuous matrix of soft segments. This unique microstructure contributes to the remarkable mechanical properties of polyurea. To maximize these properties, it is crucial to analyze the molecular structure and explore methods like formulation optimization and the incorporation of reinforcing materials or fibers. Current research efforts in polyurea applications for protective purposes primarily concentrate on construction, infrastructure, military, transportation and industrial products and facilities. Future research directions should encompass deliberate formulation design and modification, systematic exploration of factors influencing protective performance across various applications and the integration of numerical simulations and experiments to reveal the protective mechanisms of polyurea. This paper provides an extensive literature review that specifically examines the utilization of polyurea for blast and impact protection. It encompasses discussions on material optimization, protective mechanisms and its applications in blast and impact protection.
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Affiliation(s)
- Yifan Wang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Lailong Ding
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Jiayu Lin
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Xishun Qiu
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Chao Wu
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Changhao Liu
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Yicheng Tian
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Rui Zhang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Weibo Huang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Mingliang Ma
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
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6
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Wu Z, Wu JW, Michaudel Q, Jayaraman A. Investigating the Hydrogen Bond-Induced Self-Assembly of Polysulfamides Using Molecular Simulations and Experiments. Macromolecules 2023; 56:5033-5049. [PMID: 38362140 PMCID: PMC10865372 DOI: 10.1021/acs.macromol.3c01093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 06/08/2023] [Indexed: 02/17/2024]
Abstract
In this paper, we present a synergistic, experimental, and computational study of the self-assembly of N,N'-disubstituted polysulfamides driven by hydrogen bonds (H-bonds) between the H-bonding donor and acceptor groups present in repeating sulfamides as a function of the structural design of the polysulfamide backbone. We developed a coarse-grained (CG) polysulfamide model that captures the directionality of H-bonds between the sulfamide groups and used this model in molecular dynamics (MD) simulations to study the self-assembly of these polymers in implicit solvent. The CGMD approach was validated by reproducing experimentally observed trends in the extent of crystallinity for three polysulfamides synthesized with aliphatic and/or aromatic repeating units. After validation of our CGMD approach, we computationally predicted the effect of repeat unit bulkiness, length, and uniformity of segment lengths in the polymers on the extent of orientational and positional order among the self-assembled polysulfamide chains, providing key design principles for tuning the extent of crystallinity in polysulfamides in experiments. Those computational predictions were then experimentally tested through the synthesis and characterization of polysulfamide architectures.
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Affiliation(s)
- Zijie Wu
- Department
of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy St., Newark, Delaware 19716, United States
| | - Jiun Wei Wu
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Quentin Michaudel
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
- Department
of Materials Science & Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Arthi Jayaraman
- Department
of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy St., Newark, Delaware 19716, United States
- Department
of Materials Science and Engineering, University
of Delaware, 201 DuPont Hall, Newark, Delaware 19716, United States
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McLuskie A, Brodie CN, Tricarico M, Gao C, Peters G, Naden AB, Mackay CL, Tan JC, Kumar A. Manganese catalysed dehydrogenative synthesis of polyureas from diformamide and diamines. Catal Sci Technol 2023; 13:3551-3557. [PMID: 37342794 PMCID: PMC10278093 DOI: 10.1039/d3cy00284e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 05/12/2023] [Indexed: 06/23/2023]
Abstract
We report here the synthesis of polyureas from the dehydrogenative coupling of diamines and diformamides. The reaction is catalysed by a manganese pincer complex and releases H2 gas as the only by-product making the process atom-economic and sustainable. The reported method is greener in comparison to the current state-of-the-art production routes that involve diisocyanate and phosgene feedstock. We also report here the physical, morphological, and mechanical properties of synthesized polyureas. Based on our mechanistic studies, we suggest that the reaction proceeds via isocyanate intermediates formed by the manganese catalysed dehydrogenation of formamides.
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Affiliation(s)
- Angus McLuskie
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
| | - Claire N Brodie
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
| | - Michele Tricarico
- Department of Engineering Science, University of Oxford Parks Road Oxford OX13PJ UK
| | - Chang Gao
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
| | - Gavin Peters
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
| | - Aaron B Naden
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
| | | | - Jin-Chong Tan
- Department of Engineering Science, University of Oxford Parks Road Oxford OX13PJ UK
| | - Amit Kumar
- School of Chemistry, University of St. Andrews North Haugh St. Andrews KY169ST UK
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Effect of Aromatic Chain Extenders on Polyurea and Polyurethane Coatings Designed for Defense Applications. Polymers (Basel) 2023; 15:polym15030756. [PMID: 36772057 PMCID: PMC9920908 DOI: 10.3390/polym15030756] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
The present work describes the synthesis of new versatile polyurea (PU) and polyurethane (PUR) matrices, including different chain extenders, which facilitate the design of distinct, tunable properties, and high-performance derivatives. These polymers can be used for various defense and security applications, such as coatings for ballistic protection, CBRN protection, binders for energetic formulations, etc. Combining aliphatic and aromatic molecules in PU or PUR structures enables the synthesis of polymers with improved and controllable thermo-mechanical properties. Thus, for polyurea synthesis, we utilized two types of polymeric aliphatic diamines and three types of aromatic chain extenders (1,1'-biphenyl-4,4'-diamine, benzene-1,2-diamine, and 1,2-diphenylhydrazine). An analogous method was used to synthesize polyurethane films by employing one polymeric aliphatic polyol and three types of aromatic chain extenders (benzene-1,3-diol, benzene-1,4-diol, and benzene-1,2,3-triol). Subsequently, various analytic techniques (Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), single cantilever dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), frequency-dependent shear modulus survey, tensile tests, water contact angle measurements, and scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX)) have been utilized to characterize the synthesized materials and to evaluate the influence of each chain extender on their final properties.
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Tensile Properties and Fracture Mechanism of Thermal Spraying Polyurea. Polymers (Basel) 2022; 15:polym15010041. [PMID: 36616390 PMCID: PMC9824430 DOI: 10.3390/polym15010041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
In this study, polyurea was experimentally tested under various spraying temperatures and pressures. The number of holes and the pore size produced after the tensile fracture of the polyurea were counted to illustrate the effect of the various spraying temperatures and pressures on the performance of the polyurea. The tensile characteristics of polyurea were greatly influenced by the spraying temperatures and pressures, according to the experimental findings and statistical analysis. The polyurea tensile performance was best when the spraying pressure was 17.25 MPa with a spraying temperature of 70 °C. The fracture mechanism was illustrated by the silver streaking phenomenon generated during the tensile stretching process. The fracture energy was absorbed by the fracture holes and pores during silver streaking, thus creating the huge gap in tensile properties.
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An JH, Song JH, Jang HS, Roh PS, Eun HC. Comparison of Dynamic Vibration Control Techniques by the GFRPU and/or LTMD System. Polymers (Basel) 2022; 14:polym14224979. [PMID: 36433105 PMCID: PMC9696104 DOI: 10.3390/polym14224979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 11/19/2022] Open
Abstract
Reinforced concrete (RC) structures with non-seismic reinforcement details are vulnerable to earthquakes. This experimental study evaluates the efficiency of three techniques to alleviate the dynamic responses of existing structures: glass fiber-reinforced polyurea (GFRPU) reinforcement, a lever-typed tuned mass damper (LTMD) system, and a hybrid system of GFRPU and LTMD reinforcements. The lateral-resisting capacity and ductility of the GFRPU reinforcement specimen were enhanced by the material characteristics, and the dynamic responses were alleviated. The LTMD control specimen controlled the dynamic responses by the passive control system of the tuned mass damper (TMD), and the control forces to sustain its geometric motion were exerted on the specimen. The hybrid system was designed to control the dynamic responses by the GFRPU reinforcement and the LTMD control system. Four specimens, including an unreinforced specimen, were tested under external excitations, including the El Centro earthquake. The vibrations were more controlled in the order of the GFRPU reinforcement specimen, the LTMD control specimen, and the hybrid control specimen. The hybrid system was evaluated as excellent for seismic reinforcement, such as preventing abrupt failure with the lateral-resisting capacity and ductility of GFRPU and improving the dynamic control capacity by LTMD.
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Affiliation(s)
- Jae-Hyoung An
- Department of Architectural Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Jun-Hyeok Song
- Department of Architectural Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Hye-Sook Jang
- Department of Architectural Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Pil-Sung Roh
- R&J Structural Engineering Consultants, Wonju-si 26392, Republic of Korea
| | - Hee-Chang Eun
- Department of Architectural Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea
- Correspondence:
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11
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Huang W, Zhang R, Wang X, Lyu P, Ju J, Gao F, Yan S. Study of Blast Mitigation Performance and Fracture Mechanism of Polyurea under Contact Explosion. Polymers (Basel) 2022; 14:polym14173458. [PMID: 36080530 PMCID: PMC9460234 DOI: 10.3390/polym14173458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/19/2022] [Accepted: 08/19/2022] [Indexed: 11/20/2022] Open
Abstract
In order to further study the blast mitigation performance of polyurea and to investigate the protection mechanism and damage characteristics of polyurea-protected structures under contact explosion loads, based on earlier work, this paper investigated the response and energy absorption performance of polyurea under various frequency loads. Qtech T26 blast mitigation polyurea (T26 polyurea) was adopted to protect the reinforced concrete (RC) slab and damage analysis of the post-explosion specimens was carried out at micro and macro levels. The response and energy absorption capacity of the material towards different frequency loads were investigated by dynamic mechanical analysis (DMA). Protective performance of T26 polyurea on RC slab was examined with a 10 kg TNT contact explosion test. Scanning electron microscopy (SEM) was employed to analyze the microscopic fracture morphology of the typical areas of the coating after the explosion. The chemical structure changes of the blast-face coating before and after the explosion were compared by Fourier transform infrared spectroscopy (FTIR). The results show that the glass transition region of T26 polyurea is −40 °C to 10 °C, which is a large temperature range, and the microphase separation of T26 polyurea is low. It is significantly influenced by the ambient temperature and loading frequency. The energy absorption of T26 polyurea is realized through the interaction between the hard and soft segments. When the frequency is between 102 Hz and 106 Hz, the loss factor of T26 polyurea is between 0.20 and 0.31, which exhibits a good energy dissipation performance. In the contact explosion of 10 kg TNT, the fragmentation rate of the coated specimen decreased significantly compared with that of the unprotected specimen, realizing the zero fragmentation protection effect on the back-blast face. The maximum deformation area and the main energy absorption area of T26 polyurea under contact explosion is the ring area outside the longitudinal deformation area. The chemical structure of T26 polyurea changed significantly after the explosion; typically the N-H bonds, etc., were broken and the percentage of hydrogen bonding was reduced. T26 polyurea has realized the protection effect of zero fragmentation of large-equivalent contact explosion, which has a high application value for blast mitigation and blast-fragmentation prevention in actual engineering.
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Affiliation(s)
- Weibo Huang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
- Correspondence: (W.H.); (P.L.); Tel.: +86-13906485186 (W.H.)
| | - Rui Zhang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Xu Wang
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Ping Lyu
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
- Correspondence: (W.H.); (P.L.); Tel.: +86-13906485186 (W.H.)
| | - Jiahui Ju
- Qingdao Shamu Advanced Material Co., Ltd., Qingdao 266000, China
| | - Fuyin Gao
- Army Infantry Academy of PLA, Nanchang 330103, China
| | - Shuai Yan
- School of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China
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Qiao J, Zhang Q, Wu C, Wu G, Li L. Effects of Fiber Volume Fraction and Length on the Mechanical Properties of Milled Glass Fiber/Polyurea Composites. Polymers (Basel) 2022; 14:polym14153080. [PMID: 35956593 PMCID: PMC9370809 DOI: 10.3390/polym14153080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 02/04/2023] Open
Abstract
Composites of polyurea (PU) reinforced with milled glass fiber (MGf) were fabricated. The volume fraction and length of the milled glass fiber were varied to study their effects on the morphological and mechanical properties of the MGf/PU composites. The morphological attributes were characterized with scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The SEM investigations revealed a uniform distribution and arbitrary orientation of milled glass fiber in the polyurea matrix. Moreover, it seems that the composites with longer fiber exhibit better interfacial bonding. It was found from the FTIR studies that the incorporation of milled glass fiber into polyurea leads to more phase mixing and decreases the hydrogen bonding of the polyurea matrix, while having a negligible effect on the H-bond strength. The compression tests at different strain rates (0.001, 0.01, 0.1, 1, 2000 and 3000 s−1) and dynamic mechanical properties over the temperature range from −30 to 100 °C at 1 Hz were performed. Experimental results show that the compressive behavior of MGf/PU composites is nonlinear and strain-rate-dependent. Both elastic modulus and flow stress at any given strain increased with strain rate. The composites with higher fiber volume fraction and longer fiber length are more sensitive to strain rate. Furthermore, the elastic modulus, stress at 65% strain and energy absorption capability were studied, taking into account both the effect of fiber volume fraction and mean fiber length. It is noted that an increase in fiber volume fraction and fiber length leads to an increase in elastic modulus, stress at 65% strain and absorbed energy up to ~103%, 83.0% and 137.5%, respectively. The storage and loss moduli of the composites also increase with fiber volume fraction and fiber length. It can be concluded that the addition of milled glass fiber into polyurea not only improves the stiffness of the composites but also increases their energy dissipative capability.
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Affiliation(s)
- Jing Qiao
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; (Q.Z.); (C.W.); (G.W.)
- Correspondence: (J.Q.); (L.L.); Tel.: +86-451-86412164 (J.Q. & L.L.)
| | - Quan Zhang
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; (Q.Z.); (C.W.); (G.W.)
| | - Chong Wu
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; (Q.Z.); (C.W.); (G.W.)
| | - Gaohui Wu
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; (Q.Z.); (C.W.); (G.W.)
| | - Longqiu Li
- School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China
- Correspondence: (J.Q.); (L.L.); Tel.: +86-451-86412164 (J.Q. & L.L.)
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