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Bhutkar S, Millard PE, Preece JA, Zhang Z. Microplastic-Free Microcapsules Using Supramolecular Self-Assembly of Bis-Urea Molecules at an Emulsion Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:14798-14810. [PMID: 38990556 PMCID: PMC11270993 DOI: 10.1021/acs.langmuir.4c00541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 07/04/2024] [Accepted: 07/05/2024] [Indexed: 07/12/2024]
Abstract
Encapsulation technology is well established for entrapping active ingredients within an outer shell for their protection and controlled release. However, many solutions employed industrially use nondegradable cross-linked synthetic polymers for shell formation. To curb rising microplastic pollution, regulatory policies are forcing industries to substitute the use of such intentionally added microplastics with environmentally friendly alternatives. This work demonstrates a one-pot process to make microplastic-free microcapsules using supramolecular self-assembly of bis-ureas. Molecular bis-urea species generated in-situ spontaneously self-assemble at the interface of an oil-in-water emulsion via hydrogen bonding to form a shell held together by noncovalent bonds. In addition, Laponite nanodiscs were introduced in the formulation to restrict aggregation observed during the self-assembly and to reduce the porosity of the shell, leading to well-dispersed microcapsules (mean Sauter diameter d [3,2] ∼ 5 μm) with high encapsulation efficiency (∼99%). Accelerated release tests revealed an increase in characteristic release time of the active by more than an order of magnitude after encapsulation. The mechanical strength parameters of these capsules were comparable to some of the commercial, nondegradable melamine-formaldehyde microcapsules. With mild operating conditions in an aqueous environment, this technology has real potential to offer an industrially viable method for producing microplastic-free microcapsules.
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Affiliation(s)
| | | | - Jon A. Preece
- School
of Chemistry, University of Birmingham, Birmingham B15 2TT, U.K.
| | - Zhibing Zhang
- School
of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, U.K.
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2
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Ren L, Hao B, Fang W, Zhang D, Cheng H, Li Q, Yan D, Li Y, Wang Q, Zhou Z, Jin X, Cao A. Combination of modified biochar and polyurea microcapsules to co-encapsulate a fumigant via interface polymerization for controlled release and enhanced bioactivity. PEST MANAGEMENT SCIENCE 2022; 78:73-85. [PMID: 34432938 DOI: 10.1002/ps.6609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Soil fumigants-the most effective agrochemicals for managing soil-borne diseases-have been used extensively. However, high volatility, moderate toxicity and insufficient effective duration considerably limit their application. In the present study, interface polymerization was used to combine modified biochar (BC) and polyurea microcapsules (MCs) to co-encapsulate allyl isothiocyanate (AITC), developing a model fumigant for controlled release (AITC@BC-MCs). RESULTS The physical characteristics of BC modified by sand-milling were significantly improved. In addition, chemical properties and morphological features of AITC@BC-MCs characterized by integrated methods revealed successful preparation of BC-MCs. Compared with monolayer MCs, BC-MCs could significantly delay AITC release owing to the composite obstruction effect. Moreover, modifying BC endowed the cargo molecules with a pH-responsive release property. Additionally, this composite showed a longer persistent duration by prolonging AITC degradation half-life, which was 3.2-3.5-fold greater than that of the AITC technical concentrate under different soil conditions. Finally, the control efficacy of the AITC@BC-MC against pathogens, including nematodes and fungi, as well as against weeds was significantly enhanced at the same dose, but the composite did not inhibit seed germination and growth after 10 days when fumigated soil was aerated. CONCLUSION Construction of a composite encapsulation system enhanced pesticide efficacy, reduced dose via controlled release and delayed fumigant degradation in soil, indicating the great potential of this strategy for developing an effective and environmentally friendly fumigant formulation. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Lirui Ren
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- College of Science, China Agricultural University, Beijing, China
| | - Baoqiang Hao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wensheng Fang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Daqi Zhang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongyan Cheng
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qingjie Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongdong Yan
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuan Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiuxia Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhiqiang Zhou
- College of Science, China Agricultural University, Beijing, China
| | - Xi Jin
- Joint Center of Soil Remediation of Baoding University and Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Baoding, China
| | - Aocheng Cao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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3
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Polyureas Versatile Polymers for New Academic and Technological Applications. Polymers (Basel) 2021; 13:polym13244393. [PMID: 34960942 PMCID: PMC8708372 DOI: 10.3390/polym13244393] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/27/2021] [Accepted: 09/22/2021] [Indexed: 01/04/2023] Open
Abstract
Polyureas (PURs) are a competitive polymer to their analogs, polyurethanes (PUs). Whereas PUs' main functional group is carbamate (urethane), PURs contain urea. In this revision, a comprehensive overview of PUR properties, from synthesis to technical applications, is displayed. Preparative routes that can be used to obtain PURs using diisocianates or harmless reagents such as CO2 and NH3 are explained, and aterials, urea monomers and PURs are discussed; PUR copolymers are included in this discussion as well. Bulk to soft components of PUR, as well as porous materials and meso, micro or nanomaterials are evaluated. Topics of this paper include the general properties of aliphatic and aromatic PUR, followed by practical synthetic pathways, catalyst uses, aggregation, sol-gel formation and mechanical aspects.
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4
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Malatjie KI, Mbuli BS, Moutloali RM, Ngila CJ. An In Situ Incorporation of Acrylic Acid and ZnO Nanoparticles into Polyamide Thin Film Composite Membranes for Their Effect on Membrane pH Responsive Behavior. MEMBRANES 2021; 11:membranes11120910. [PMID: 34940411 PMCID: PMC8704247 DOI: 10.3390/membranes11120910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 11/24/2022]
Abstract
This paper focuses on an in situ interfacial polymerization modification of polyamide thin film composite membranes with acrylic acid (AA) and zinc oxide (ZnO) nanoparticles. Consequent to this modification, the modified polyamide thin film composite (PA–TFC) membranes exhibited enhanced water permeability and Pb (II) heavy metal rejection. For example, the 0.50:1.50% ZnO/AA modified membranes showed water permeability of 29.85 ± 0.06 L·m−2·h−1·kPa−1 (pH 3), 4.16 ± 0.39 L·m−2·h−1·kPa−1 (pH 7), and 2.80 ± 0.21 L·m−2·h−1·kPa−1 1 (pH 11). This demonstrated enhanced pH responsive properties, and improved water permeability properties against unmodified membranes (2.29 ± 0.59 L·m−2·h−1·kPa−1, 1.79 ± 0.27 L·m−2·h−1·kPa−1, and 0.90 ± 0.21 L·m−2·h−1·kPa−1, respectively). Furthermore, the rejection of Pb (II) ions by the modified PA–TFC membranes was found to be 16.11 ± 0.12% (pH 3), 30.58 ± 0.33% (pH 7), and 96.67 ± 0.09% (pH 11). Additionally, the membranes modified with AA and ZnO/AA demonstrated a significant pH responsiveness compared to membranes modified with only ZnO nanoparticles and unmodified membranes. As such, this demonstrated the swelling behavior due to the inherent “gate effect” of the modified membranes. This was illustrated by the rejection and water permeation behavior, hydrophilic properties, and ion exchange capacity of the modified membranes. The pH responsiveness for the modified membranes was due to the –COOH and –OH functional groups introduced by the AA hydrogel and ZnO nanoparticles.
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Affiliation(s)
- Kgolofelo I. Malatjie
- Department of Chemical Sciences, University of Johannesburg, Johannesburg 2028, South Africa; (K.I.M.); (R.M.M.); (C.J.N.)
- Department of Science and Innovation/Mintek Nanotechnology Innovation Centre-Water Research Node, University of Johannesburg, Doornfontein, Johannesburg 2028, South Africa
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Johannesburg 1710, South Africa
| | - Bhekani S. Mbuli
- Department of Chemical Sciences, University of Johannesburg, Johannesburg 2028, South Africa; (K.I.M.); (R.M.M.); (C.J.N.)
- Department of Science and Innovation/Mintek Nanotechnology Innovation Centre-Water Research Node, University of Johannesburg, Doornfontein, Johannesburg 2028, South Africa
- Correspondence:
| | - Richard M. Moutloali
- Department of Chemical Sciences, University of Johannesburg, Johannesburg 2028, South Africa; (K.I.M.); (R.M.M.); (C.J.N.)
- Department of Science and Innovation/Mintek Nanotechnology Innovation Centre-Water Research Node, University of Johannesburg, Doornfontein, Johannesburg 2028, South Africa
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Johannesburg 1710, South Africa
| | - Catherine J. Ngila
- Department of Chemical Sciences, University of Johannesburg, Johannesburg 2028, South Africa; (K.I.M.); (R.M.M.); (C.J.N.)
- Department of Science and Innovation/Mintek Nanotechnology Innovation Centre-Water Research Node, University of Johannesburg, Doornfontein, Johannesburg 2028, South Africa
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Yu F, Wang Y, Zhao Y, Chou J, Li X. Preparation of Polyurea Microcapsules by Interfacial Polymerization of Isocyanate and Chitosan Oligosaccharide. MATERIALS (BASEL, SWITZERLAND) 2021; 14:3753. [PMID: 34279323 PMCID: PMC8269919 DOI: 10.3390/ma14133753] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/20/2021] [Accepted: 06/30/2021] [Indexed: 01/15/2023]
Abstract
(2-((1-(4-chlorophenyl)-1H-pyrazol-3-yl)oxy)-N-(3,4-dichlorophenyl)-propanamide) is a new oil-soluble compound with good fungicidal activity against Rhizoctonia solani. Chitosan oligosaccharide (COS) is the depolymerization product of chitosan and can be developed into biological pesticides, growth regulators, and fertilizers due to its various bioactivities. COS is an oligomer of β- (1 → 4)-linked d -glucosamine and can be taken as a polyamine. In this study, microcapsules were prepared by interfacial polymerization of oil-soluble methylene diphenyl diisocyanate and water-soluble COS. The effects of several key preparation parameters, e.g., emulsifier dosage, agitation rate during emulsification, and core/shell ratio, on properties of the microcapsules such as the encapsulation efficiency, particle size, and size distribution were investigated. The microcapsules were characterized by infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy, etc., and the encapsulation efficiency and release behaviors were investigated. The results show that the microcapsules have a smooth surface and 93.3% of encapsulation efficiency. The microcapsules showed slow-release behavior following a first-order kinetic equation, and the accumulative release rates of the microcapsules with core/shell mass ratios of 8.0/4.0, 8.0/5.0, and 8.0/6.0, were 95.5%, 91.4%, and 90.1%, respectively, on day 30. Due to many high biological activities, biodegradability, and the pure nature of COS, microcapsules formed from COS are promising for applications in controlled release of pesticides, growth regulators, and fertilizer.
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Affiliation(s)
- Fuqiang Yu
- Department of Materials Physics and Chemistry, School of Materials Science and Engineering, and Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819, china
- State Key Laboratory for the Discovery and Development of Novel Pesticides, Shenyang Sinochem Agrochemicals R&D Co., Ltd., Shenyang 110021, China
| | - Ying Wang
- State Key Laboratory for the Discovery and Development of Novel Pesticides, Shenyang Sinochem Agrochemicals R&D Co., Ltd., Shenyang 110021, China
| | - Yan Zhao
- Jihua Laboratory, Nanhai, Foshan 528200, China
| | - Jingyu Chou
- State Key Laboratory for the Discovery and Development of Novel Pesticides, Shenyang Sinochem Agrochemicals R&D Co., Ltd., Shenyang 110021, China
| | - Xiaowu Li
- Department of Materials Physics and Chemistry, School of Materials Science and Engineering, and Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819, china
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6
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Rubio Hernández-Sampelayo A, Navarro R, Marcos-Fernández Á. Preparation of High Molecular Weight Poly(urethane-urea)s Bearing Deactivated Diamines. Polymers (Basel) 2021; 13:1914. [PMID: 34207525 PMCID: PMC8229936 DOI: 10.3390/polym13121914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/21/2021] [Accepted: 06/07/2021] [Indexed: 11/21/2022] Open
Abstract
The synthesis of poly(urethane-urea) (PUUs) bearing deactivated diamines within the backbone polymer chain is presented. Several deactivated diamines present interesting properties for several applications in the biomaterial field due to their attractive biocompatibility. Through an activation with Chloro-(trimethyl)silane (Cl-TMS) during the polymerization reaction, the reactivity of these diamines against diisocyanates was triggered, leading to PUUs with high performance. Indeed, through this activation protocol, the obtained molecular weights and mechanical features increased considerably respect to PUUs prepared following the standard conditions. In addition, to demonstrate the feasibility and versatility of this synthetic approach, diisocyanate with different reactivity were also addressed. The experimental work is supported by calculations of the electronic parameters of diisocyanate and diamines, using quantum mechanical methods.
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Affiliation(s)
- Alejandra Rubio Hernández-Sampelayo
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain; (A.R.H.-S.); (Á.M.-F.)
- Escuela Internacional de Doctorado de la UNED, Universidad Nacional de Educación a Distancia (UNED), C/Bravo Murillo, 38, 28015 Madrid, Spain
| | - Rodrigo Navarro
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain; (A.R.H.-S.); (Á.M.-F.)
- Interdisciplinary Platform for “Sustainable Plastics towards a Circular Economy” (SUSPLAST-CSIC, Madrid, Spain
| | - Ángel Marcos-Fernández
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain; (A.R.H.-S.); (Á.M.-F.)
- Interdisciplinary Platform for “Sustainable Plastics towards a Circular Economy” (SUSPLAST-CSIC, Madrid, Spain
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7
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A Multi-Scale Approach to Microencapsulation by Interfacial Polymerization. Polymers (Basel) 2021; 13:polym13040644. [PMID: 33671501 PMCID: PMC7926481 DOI: 10.3390/polym13040644] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/09/2021] [Accepted: 02/15/2021] [Indexed: 11/23/2022] Open
Abstract
This work applies a multi-scale approach to the microencapsulation by interfacial polymerization. Such microencapsulation is used to produce fertilizers, pesticides and drugs. In this study, variations at three different scales (molecular, microscopic and macroscopic) of product design (i.e., product variables, process variables and properties) are considered simultaneously. We quantify the effect of the formulation, composition and pH change on the microcapsules’ properties. Additionally, the method of measuring the strength of the microcapsules by crushing a sample of microcapsules’ suspension was tested. Results show that the xylene release rate in the microcapsules decreases when the amine functionality is greater due to a stronger crosslinking. Such degree of crosslinking increases the compression force over the microcapsules and improves their appearance. When high levels of amine concentration are used, the initial pH values in the reaction are also high which leads to agglomeration. This study provides a possible explanation to the aggregation based on the kinetic and thermodynamic controls in reactions and shows that the pH measurements account for the polyurea reaction and carbamate formation, which is a reason why this is not a suitable method to study kinetics of polymerization. Finally, the method used to measure the compressive strength of the microcapsules detected differences in formulations and composition with low sensibility.
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8
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Ren L, Huang B, Fang W, Zhang D, Cheng H, Song Z, Yan D, Li Y, Wang Q, Zhou Z, Cao A. Multi-Encapsulation Combination of O/W/O Emulsions with Polyurea Microcapsules for Controlled Release and Safe Application of Dimethyl Disulfide. ACS APPLIED MATERIALS & INTERFACES 2021; 13:1333-1344. [PMID: 33351598 DOI: 10.1021/acsami.0c16613] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Dimethyl disulfide (DMDS), a promising alternative fumigant, has been highly desirable for excellent management of soil pests and diseases. However, high volatility and moderate toxicity of this sulfide limit its application. To address these issues, a novel controlled release formulation of DMDS was proposed employing multiple emulsions and polyurea microcapsules (DMDS@MEs-MCs). The successful combination of the two technologies was revealed by confocal laser scanning microscopy, scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared. According to the multiple encapsulation structure, the encapsulation efficiency decreased by only 3.13% after thermal storage, compared with a 15.21% decrease of microcapsules made with only a monolayer film. DMDS@MEs-MCs could effectively control the release of active ingredient, which increased applicator and environmental safety during application. Moreover, it could be facilely used by spraying and drip irrigation instead of a special fumigation device. The innovative formulation exhibited better control efficacy on soil pathogens (Fusarium spp. and Phytophthora spp.) and root-knot nematodes (Meloidogyne spp.) than DMDS technical concentration (DMDS TC). In addition, it did not inhibit seed germination after 10 days when the plastic film was removed from the fumigated soil. This method appears to be of broad interest for the development of safe and handy fumigant application.
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Affiliation(s)
- Lirui Ren
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- College of Science, China Agricultural University, Beijing 100193, China
| | - Bin Huang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Wensheng Fang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Daqi Zhang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Hongyan Cheng
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Zhaoxin Song
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Dongdong Yan
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Beijing Innovation Consortium of Agriculture Research System, Beijing 100029, China
| | - Yuan Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Beijing Innovation Consortium of Agriculture Research System, Beijing 100029, China
| | - Qiuxia Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Beijing Innovation Consortium of Agriculture Research System, Beijing 100029, China
| | - Zhiqiang Zhou
- College of Science, China Agricultural University, Beijing 100193, China
| | - Aocheng Cao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Beijing Innovation Consortium of Agriculture Research System, Beijing 100029, China
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9
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Yang X. Monitoring the Interfacial Polymerization of Piperazine and Trimesoyl Chloride with Hydrophilic Interlayer or Macromolecular Additive by In Situ FT-IR Spectroscopy. MEMBRANES 2020; 10:E12. [PMID: 31936126 PMCID: PMC7022637 DOI: 10.3390/membranes10010012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/26/2019] [Accepted: 01/06/2020] [Indexed: 12/01/2022]
Abstract
The interfacial polymerization (IP) of piperazine (PIP) and trimesoyl chloride (TMC) has been extensively utilized to synthesize nanofiltration (NF) membranes. However, it is still a huge challenge to monitor the IP reaction, because of the fast reaction rate and the formed ultra-thin film. Herein, two effective strategies were applied to reduce the IP reaction rate: (1) the introduction of hydrophilic interlayers between the porous substrate and the formed polyamide layer, and (2) the addition of macromolecular additives in the aqueous solution of PIP. As a result, in situ Fourier transform infrared (FT-IR) spectroscopy was firstly used to monitor the IP reaction of PIP/TMC with hydrophilic interlayers or macromolecular additives in the aqueous solution of PIP. Moreover, the formed polyamide layer growth on the substrate was studied in a real-time manner. The in situ FT-IR experimental results confirmed that the IP reaction rates were effectively suppressed and that the formed polyamide thickness was reduced from 138 ± 24 nm to 46 ± 2 nm according to TEM observation. Furthermore, an optimized NF membrane with excellent performance was consequently obtained, which included boosted water permeation of about 141-238 (L/m2·h·MPa) and superior salt rejection of Na2SO4 > 98.4%.
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Affiliation(s)
- Xi Yang
- Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China
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10
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Li BX, Li XX, Liu Y, Zhang DX, Lin J, Mu W, Liu F. Easily Tunable Membrane Thickness of Microcapsules by Using a Coordination Assembly on the Liquid-Liquid Interface. Front Chem 2018; 6:387. [PMID: 30246007 PMCID: PMC6137620 DOI: 10.3389/fchem.2018.00387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/09/2018] [Indexed: 11/23/2022] Open
Abstract
A model solvent, 1,3,5-trimethylbenzene, was encapsulated using coordination assembly between metal ions and tannic acid to reveal the deposition of coordination complexes on the liquid-liquid interface. The deposition was confirmed by zeta potential, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Scanning electron microscopy and transmission electron microscopy were integrated to characterize the microcapsules (MCs). According to atomic force microscopy height analysis, membrane thickness of the MCs increased linearly with sequential deposition. For MCs prepared using the Fe3+-TA system, the average membrane thicknesses of MCs prepared with 2, 4, 6, and 8 deposition cycles were determined as 31.3 ± 4.6, 92.4 ± 15.0, 175.4 ± 22.1, and 254.8 ± 24.0 nm, respectively. Dissolution test showed that the release profiles of all the four tested MCs followed Higuchi kinetics. Membrane thicknesses of MCs prepared using the Ca2+-TA system were much smaller. We can easily tune the membrane thickness of the MCs by adjusting metal ions or deposition cycles according to the application requirements. The convenient tunability of the membrane thickness can enable an extensive use of this coordination assembly strategy in a broad range of applications.
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Affiliation(s)
- Bei-xing Li
- Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an, China
- Research Center of Pesticide Environmental Toxicology, Shandong Agricultural University, Tai'an, China
| | - Xiao-xu Li
- Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an, China
| | - Yang Liu
- Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an, China
| | - Da-xia Zhang
- Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an, China
- Research Center of Pesticide Environmental Toxicology, Shandong Agricultural University, Tai'an, China
| | - Jin Lin
- Research Center of Pesticide Environmental Toxicology, Shandong Agricultural University, Tai'an, China
| | - Wei Mu
- Research Center of Pesticide Environmental Toxicology, Shandong Agricultural University, Tai'an, China
| | - Feng Liu
- Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an, China
- Research Center of Pesticide Environmental Toxicology, Shandong Agricultural University, Tai'an, China
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11
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Nowbahar A, Mansard V, Mecca JM, Paul M, Arrowood T, Squires TM. Measuring Interfacial Polymerization Kinetics Using Microfluidic Interferometry. J Am Chem Soc 2018; 140:3173-3176. [PMID: 29432004 DOI: 10.1021/jacs.7b12121] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A range of academic and industrial fields exploit interfacial polymerization in producing fibers, capsules, and films. Although widely used, measurements of reaction kinetics remain challenging and rarely reported, due to film thinness and reaction rapidity. Here, polyamide film formation is studied using microfluidic interferometry, measuring monomer concentration profiles near the interface during the reaction. Our results reveal that the reaction is initially controlled by a reaction-diffusion boundary layer within the organic phase, which allows the first measurements of the rate constant for this system.
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Affiliation(s)
- Arash Nowbahar
- Department of Chemical Engineering , University of California , Santa Barbara , California 93106 , United States
| | - Vincent Mansard
- Laboratory for Analysis and Architecture of Systems (LAAS-CNRS) Toulouse , 31400 Toulouse , France
| | - Jodi M Mecca
- Formulation Science, Core Research and Development , Dow Chemical Company , Midland , Michigan 48674 , United States
| | - Mou Paul
- Dow Water & Process Solutions , Dow Chemical Company , Edina , Minnesota 55439 , United States
| | - Tina Arrowood
- Dow Water & Process Solutions , Dow Chemical Company , Edina , Minnesota 55439 , United States
| | - Todd M Squires
- Department of Chemical Engineering , University of California , Santa Barbara , California 93106 , United States
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12
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Sriramulu D, Turaga SP, Bettiol AA, Valiyaveettil S. Oriented perylene incorporated optically anisotropic 2D silica films. RSC Adv 2017. [DOI: 10.1039/c7ra05036d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Structurally oriented, optically anisotropic silica films prepared at the liquid–liquid interface.
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Affiliation(s)
- Deepa Sriramulu
- Materials Research Laboratory
- Department of Chemistry
- National University of Singapore
- Singapore 117543
| | | | | | - Suresh Valiyaveettil
- Materials Research Laboratory
- Department of Chemistry
- National University of Singapore
- Singapore 117543
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13
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DSouza R, Sriramulu D, Valiyaveettil S. Topology and porosity modulation of polyurea films using interfacial polymerization. RSC Adv 2016. [DOI: 10.1039/c5ra27108h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Polyurea films with controllable topologies and porosities were obtained by reacting different amines with hexamethyl diisocyanate at the liquid–liquid interface.
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Affiliation(s)
- Roshan DSouza
- Materials Research Laboratory
- Department of Chemistry
- National University of Singapore
- Singapore 117543
| | - Deepa Sriramulu
- Materials Research Laboratory
- Department of Chemistry
- National University of Singapore
- Singapore 117543
| | - Suresh Valiyaveettil
- Materials Research Laboratory
- Department of Chemistry
- National University of Singapore
- Singapore 117543
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14
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Piradashvili K, Alexandrino EM, Wurm FR, Landfester K. Reactions and Polymerizations at the Liquid–Liquid Interface. Chem Rev 2015; 116:2141-69. [DOI: 10.1021/acs.chemrev.5b00567] [Citation(s) in RCA: 156] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Keti Piradashvili
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | | | - Frederik R. Wurm
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Katharina Landfester
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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15
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Li B, Guan L, Wang K, Zhang D, Wang W, Liu F. Formula and process optimization of controlled-release microcapsules prepared using a coordination assembly and the response surface methodology. J Appl Polym Sci 2015. [DOI: 10.1002/app.42865] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- BeiXing Li
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
- Research Center of Pesticide Environmental Toxicology; Shandong Agricultural University; Tai'an Shandong People's Republic of China
| | - Lei Guan
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
| | - Kai Wang
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
| | - DaXia Zhang
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
- Research Center of Pesticide Environmental Toxicology; Shandong Agricultural University; Tai'an Shandong People's Republic of China
| | - WeiChang Wang
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
| | - Feng Liu
- Key Laboratory of Pesticide Toxicology & Application Technique, Department of Plant Protection; Shandong Agricultural University; Tai'an Shandong People's Republic of China
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16
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Rosa N, Martins GV, Bastos MMSM, Gois JR, Coelho JFJ, Marques J, Tavares CJ, Magalhães FD. Preparation of robust polyamide microcapsules by interfacial polycondensation of p-phenylenediamine and sebacoyl chloride and plasticization with oleic acid. J Microencapsul 2015; 32:349-57. [PMID: 26052719 DOI: 10.3109/02652048.2015.1028494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Microcapsules produced by interfacial polycondensation of p-phenylenediamine (PPD) and sebacoyl chloride (SC) were studied. The products were characterized in terms of morphology, mean diameter and effectiveness of dodecane encapsulation. The use of Tween 20 as dispersion stabilizer, in comparison with polyvinyl alcohol (PVA), reduced considerably the mean diameter of the microcapsules and originated smoother wall surfaces. When compared to ethylenediamine (EDA), microcapsules produced with PPD monomer were more rigid and brittle, prone to fracture during processing and ineffective retention of the core liquid. The use of diethylenetriamine (DETA) cross-linker in combination with PPD did not decrease capsule fragility. On the other hand, addition of a small fraction of oleic acid to the organic phase remarkably improved wall toughness and lead to successful encapsulation of the core-oil. Oleic acid is believed to act as a plasticizer. Its incorporation in the polymeric wall was demonstrated by FTIR and (1)H-NMR.
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Affiliation(s)
- Natacha Rosa
- LEPABE, Faculdade de Engenharia, Universidade do Porto , rua Dr. Roberto Frias , Portugal
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17
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Polenz I, Brosseau Q, Baret JC. Monitoring reactive microencapsulation dynamics using microfluidics. SOFT MATTER 2015; 11:2916-23. [PMID: 25705975 PMCID: PMC4424838 DOI: 10.1039/c5sm00218d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 02/16/2015] [Indexed: 05/24/2023]
Abstract
We use microfluidic polydimethylsiloxane (PDMS) devices to measure the kinetics of reactive encapsulations occurring at the interface of emulsion droplets. The formation of the polymeric shell is inferred from the droplet deformability measured in a series of expansion-constriction chambers along the microfluidic chip. With this tool we quantify the kinetic processes governing the encapsulation at the very early stage of shell formation with a time resolution of the order of the millisecond for overall reactions occurring in less than 0.5 s. We perform a comparison of monomer reactivities used for the encapsulation. We study the formation of polyurea microcapsules (PUMCs); the shell formation proceeds at the water-oil interface by an immediate reaction of amines dissolved in the aqueous phase and isocyanates dissolved in the oil phase. We observe that both monomers contribute differently to the encapsulation kinetics. The kinetics of the shell formation process at the oil-in-water (O/W) experiments significantly differs from the water-in-oil (W/O) systems; the component dissolved in the continuous phase has the largest impact on the kinetics. In addition, we quantified the retarding effect on the encapsulation kinetics by the interface stabilizing agent (surfactant). Our approach is valuable for quantifying in situ reactive encapsulation processes and provides guidelines to generate microcapsules with soft interfaces of tailored and controllable interfacial properties.
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Affiliation(s)
- Ingmar Polenz
- Max-Planck Institute for Dynamics and Self-Organization , Am Fassberg 17 , Göttingen , Germany . ; Tel: +49 551 5176 291
| | - Quentin Brosseau
- Max-Planck Institute for Dynamics and Self-Organization , Am Fassberg 17 , Göttingen , Germany . ; Tel: +49 551 5176 291
| | - Jean-Christophe Baret
- Max-Planck Institute for Dynamics and Self-Organization , Am Fassberg 17 , Göttingen , Germany . ; Tel: +49 551 5176 291
- CNRS , Univ. Bordeaux , CRPP , UPR 8641 , Soft Micro Systems , 115 Avenue Schweitzer , 33600 Pessac , France .
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18
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Yang Y, Jiang X, Zhu X, Kong XZ. A facile pathway to polyurea nanofiber fabrication and polymer morphology control in copolymerization of oxydianiline and toluene diisocyanate in acetone. RSC Adv 2015. [DOI: 10.1039/c4ra15309j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Polyurea nanofibers, of high thermal stability and solvent resistance, were obtained through simple precipitation polymerization of TDI and ODA in acetone at 30 °C.
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Affiliation(s)
- Yanan Yang
- College of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
| | - Xubao Jiang
- College of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
| | - Xiaoli Zhu
- College of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
| | - Xiang Zheng Kong
- College of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
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19
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Locatelli P, Woutters S, Lindsay C, Schroeder SLM, Hobdell JH, Saiani A. Synthesis of polyurea–polyether nanoparticles via spontaneous nanoprecipitation. RSC Adv 2015. [DOI: 10.1039/c5ra03662c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synthesis of polyurea–polyether core–shell nano-particles via spontaneous precipitation.
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Affiliation(s)
- Pietro Locatelli
- School of Materials
- The University of Manchester
- M13 9PL Manchester
- UK
| | | | | | | | | | - Alberto Saiani
- School of Materials
- The University of Manchester
- M13 9PL Manchester
- UK
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20
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Perignon C, Ongmayeb G, Neufeld R, Frere Y, Poncelet D. Microencapsulation by interfacial polymerisation: membrane formation and structure. J Microencapsul 2014; 32:1-15. [DOI: 10.3109/02652048.2014.950711] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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21
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Wu X, Zhao Q, Zhao G, Liu J, Wang X. Tribological Properties of Alkylphenyl Diphosphates as High-Performance Antiwear Additive in Lithium Complex Grease and Polyurea Grease for Steel/Steel Contacts at Elevated Temperature. Ind Eng Chem Res 2014. [DOI: 10.1021/ie500105v] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xinhu Wu
- State
Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical
Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
| | - Qin Zhao
- State
Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical
Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
- Graduate School of Chinese Academy of Sciences, Beijing 100039, People’s Republic of China
| | - Gaiqing Zhao
- State
Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical
Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
| | - Junming Liu
- State
Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical
Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
| | - Xiaobo Wang
- State
Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical
Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
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22
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Mbuli BS, Nxumalo EN, Krause RW, Pillay VL, Oren Y, Linder C, Mamba BB. Modification of polyamide thin-film composite membranes with amino-cyclodextrins and diethylamino-cyclodextrins for water desalination. Sep Purif Technol 2013. [DOI: 10.1016/j.seppur.2013.09.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Matthews TD, Yan H, Cahill DG, Coronell O, Mariñas BJ. Growth dynamics of interfacially polymerized polyamide layers by diffuse reflectance spectroscopy and Rutherford backscattering spectrometry. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2012.11.040] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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24
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Yuan F, Wang Z, Li S, Wang J, Wang S. Formation–structure–performance correlation of thin film composite membranes prepared by interfacial polymerization for gas separation. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.07.035] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Zhang Y, Rochefort D. Characterisation and applications of microcapsules obtained by interfacial polycondensation. J Microencapsul 2012; 29:636-49. [DOI: 10.3109/02652048.2012.676092] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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26
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Cai M, Liang Y, Zhou F, Liu W. Tribological properties of novel imidazolium ionic liquids bearing benzotriazole group as the antiwear/anticorrosion additive in poly(ethylene glycol) and polyurea grease for steel/steel contacts. ACS APPLIED MATERIALS & INTERFACES 2011; 3:4580-4592. [PMID: 22026637 DOI: 10.1021/am200826b] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The imidazolium ionic liquids (ILs) bearing benzotriazole group were synthesized and evaluated as antiwear (AW) and anticorrosion additive in poly(ethylene glycol) (PEG) and polyurea grease for steel/steel contacts at room temperature and 150 °C. The physical properties of the synthetic ILs and PEG with the additive were measured. The anticorrosion property of the synthetic ILs was assessed via the accelerated corrosion test and copper strip corrosion test, which reveals the excellent anticorrosion properties in comparison with pure PEG and the selected conventional ILs having no benzotriazole group. Tribological results indicated that these ILs as the additives could effectively reduce friction and wear of sliding pairs in PEG and also in polyurea grease. The tribological properties were generally better than the normally used zincdialkyldithiophosphate-based additive package (T204) in polyurea grease. The wear mechanisms are tentatively discussed according to the morphology observation of worn surfaces of steel discs by scanning electron microscope (SEM) and the surface composition analysis by X-ray photoelectron spectroscopy (XPS).
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Affiliation(s)
- Meirong Cai
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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27
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Understanding interfacial polycondensation: Experiments on polyurea system and comparison with theory. POLYMER 2010. [DOI: 10.1016/j.polymer.2010.01.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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28
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Oizerovich-Honig R, Raim V, Srebnik S. Simulation of thin film membranes formed by interfacial polymerization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:299-306. [PMID: 19824686 DOI: 10.1021/la9024684] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Interfacial polymerization is widely used today for the production of ultrathin films for encapsulation, chemical separations, and desalination. Polyamide films, in particular, are employed in manufacturing of reverse osmosis and nanofiltration membranes. While these materials show excellent salt rejection, they have rather low water permeability, both properties that apparently stem from the rigid cross-linked structure. An increasing amount of experimental research on membranes of different chemistries and membrane characterization suggests the importance of other factors (such as unreacted functional groups and surface roughness) in determining membrane performance. We developed a molecular simulation model to qualitatively study the effects of various synthesis conditions on membrane performance, in terms of its estimated porosity and permeability. The model is of an interfacial aggregation process of two types of functional monomers. Film growth with time and structural characteristics of the final film are compared with predictions of existing theories and experimental observations.
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Affiliation(s)
- Rachel Oizerovich-Honig
- Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa, Israel 32000
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29
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A comprehensive model for kinetics and development of film structure in interfacial polycondensation. POLYMER 2009. [DOI: 10.1016/j.polymer.2009.09.072] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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30
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Tadjoa O, Cassagnau P, Chapel JP. Two-dimensional sol-gel transition in silica alkoxides at the air/water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:11205-11209. [PMID: 19739619 DOI: 10.1021/la901980n] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have investigated the 2D viscoelastic behavior of the reactive sol-gel transition of silica alkoxides deposited at the air/acidic water interface of a Langmuir trough by oscillatory interfacial rheology. The storage and loss moduli increased with time as the hydrolysis-condensation reaction took place. There was evidence of a 2D gel point, which was discussed within the percolation theory framework. The power law dependence value of n=0.63 was similar to those found for bulk systems. The final network had a low fractal dimension value of df=1.17 (for a 2D system) indicating a rather open structure, in agreement with acidic catalysis, and a somewhat low effective modulus of 20 MPa.
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