JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 3.6
Chaogang Fan,Qingyun Ge,Shujuan Lu,Xianshe Feng,Yingfeng Tu,Li Jia,Shaohui Lin,Qinmin Pan,Flora T. T. Ng
A Salen-Co(III)-Cl catalyzed copolymerization strategy is developed for the controlled synthesis of polycarbonate- b -polyester block copolymers through a one-pot process involving CO 2 , 4-vinyl-1-cyclohexene-1,2-epoxy (VCHO), and ε-caprolactone (ε-CL). This procedure is extended to the copolymerization of CO 2 , VCHO, and lactide. The catalytic system is designed and optimized with temperature and CO 2 acting as triggers to switch between CO 2 /epoxide copolymerization and ε-CL homopolymerization. In addition, introducing water as the chain transfer agent reduced the polydispersity index (PDI) of the block copolymers. The copolymer composition can be controlled by adjusting the concentration ratio of epoxides and ε-CL, yielding copolymers with carbonate molar ratios ranging from 14% to 67%. The block copolymers exhibit enhanced thermal stability, and the glass transition temperature ( T g ) can be controlled by adjusting the block composition. Graphical Polycarbonate- b -polyester was prepared via the Salen-Cobalt complex catalyzed copolymerization of CO 2 , epoxide, and ε-caprolactone in one pot. Copolymerization of CO 2 and epoxide and homopolymerization of ε-caprolactone were switched by the control of CO 2 and temperature. By introducing H 2 O as a chain transfer agent, polyester- b -polycarbonate- b -polyester with lower PDI could be obtained.
研究领域:
材料科学
·
催化化学
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2021
·
IF 5.161
Junchao Fu,Haojie Yu,Li Wang,Ruixue Liang,Chuyin Zhang,Meijin Jin
To achieve the high dispersion of SiO 2 nanoparticles in polyurethane acrylate resin, the titanate coupling agent, PN-102, was used as the surface modifier to prepare the modified SiO 2 nanoparticles (Si-PN102-5) with small particle size and good dispersion ability in PUA-6 resin. Accordingly, hydrophilic SiO 2 (Si-380) and hydrophobic SiO 2 (Si-115) were introduced into PUA-6 resin to prepare the corresponding composite coatings, so as to investigate the effects of SiO 2 nanoparticles modified with different surface modifiers on the properties of PUA / SiO 2 composite coatings. The properties of PUA / SiO 2 composite coatings were characterized by the tests of FT-IR, AFM, SEM, DMA, TG and so on. The FT-IR and XPS results show that PN-102 had functionalized the Si-PN102-5 particle surface successfully. The TEM test displays that the particle size of SiO 2 was almost unchanged before and after modification, maintaining at about 20–30 nm. The SEM, DMA and tensile test reveal that Si-PN102-5 not only blocks the interaction and accumulation of nanoparticles, but also enhances the interface interaction with polymer chains through chain entanglement, which endows Si-PN102-5-5% composite coatings with highest mechanical strength among the other prepared coatings, reaching to 11.0 ± 0.1 MPa in tensile strength and 9.4 ± 3.0% in elongation at break. The pencil hardness of the prepared Si-PN102-5-5% composite coating could reach to 5H which is higher than the commercial PUA-6 based coating, and it also displayed good adhesion (4B) and flexibility (3 mm). The TG results show that all of prepared composite coatings display good thermal stability with a decomposition temperature of higher than 250 °C.
研究领域:
材料科学
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表面化学
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产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2019
·Vol. 77
·期 6
·2873-2887
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IF 1.858
Huang Aimin,Wei Liping,Zhao Zengyan,Wei Guodong,Zhang Yanjuan,Huang Zuqiang,Li Xuanhai,Hu Huayu,Qin Xingzhen,Yang Mei
A simple, green, and efficient mechanical activation-assisted esterification (MAE) technology was developed for the preparation of cellulose acetate butyrate (CAB), which was used as film-former for pearlescent coating. In addition, CAB was also prepared by a traditional liquid phase esterification (LPE) method for comparing the structures and characteristics of the CABs prepared by these two technologies. 1 H and 13 C NMR confirmed that CAB was successfully produced, and the degree of substitution of acetyl and butyryl groups was also calculated. The crystal structure and molar mass of the CABs prepared by MAE and LPE methods were dissimilar, ascribing to different reaction systems and characteristics. FTIR, SEM, and transparency analyses were used to investigate the chemical structure and surface characteristics of CAB films, and appearance, glossiness, rub resistance, and ethanol resistance measurements were carried out to investigate the surface and wear characteristics of CAB/pearlescent coating films. The results indicated that the surface and wear characteristics of the films based on MAE- and LPE-prepared CABs were similar to the same reaction time, and the interfacial adhesion and compatibility among components significantly affected the characteristics of the films.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 6
·51622
·
IF 3.125
Ying Li,Jun Shen,Siqi Zhang,Weidong Wang,Yu Chen,Lin Li
Biodegradable cationic waterborne polyurethanes (WPUs) were successfully prepared using poly(caprolactone) diol as the soft segment. To improve the mechanical performance, adhesive strength and water resistance of the WPU films, different amounts of trimethylol propane monooleate (TMPM) containing biodegradable long-branched aliphatic chains were incorporated in the PU structure. The T-peel strength of WPU-3 reached 42.8 N/25 mm, which was about 324% higher than that of WPU (10.1 N/25 mm) without TMPM. On the other hand, the elongation at break of WPU-5 was 811%. On enhancing the TMPM content from 0 to 7.8 wt %, the surface tension decreased from 53.6 to 41.5 mN/m and the water contact angle of the WPU films increased from 52.4 to 81.0°, whereas the water absorption was observed to decrease from 15.6% to 9.6%. The fracture mechanism of the WPU films transformed from the brittle failure to the ductile fracture. The experiment results showed the cationic WPU modified by TMPM displayed excellent film-forming property flexibility and adhesion, the surface tension of WPU dispersion and crystallinity of the resulting film were significantly reduced. For the first time, a biodegradable cationic WPU has been prepared by modification with TMPM, which can be employed for constructing the eco-friendly biodegradable cationic WPUs.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
Protection of Metals and Physical Chemistry of Surfaces
·
2019
·Vol. 55
·期 3
·495-501
·
IF 0.787
Lijun Chen,Shao Tantan,Gong Yilu,Wang Xiuming
The novel poly (VAC-VeoVa-HFMA-BZMA) latex was successfully prepared via semicontinuous seeded emulsion polymerization which vinyl acetate (VAc) and vinyl ester of neodecanoic acid (VeoVa10) were main monomer, hexafluorobutyl methacrylate (HFMA) and benzyl methacrylate (BZMA) were used as functional monomer. Dodecyl benzene sulfonic acid sodium (SDBS), octylphenol polyoxyethylene ether (OP-10) and potassium persulfate (KPS) were used to be mixed emulsifier and initiator, respectively. The structure of the resultant latex is determined by Fourier transform infrared spectroscopy spectrum (FTIR). The thermal performances of latex film are studied via the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The average particle size of the latex is characterized by the dynamic light scattering(DLS).Water contact angle (WCA) is used to test the wetting property of the novel poly (VAC-VeoVa-HFMA-BZMA) latex film. The condition of synthesizing the latex was studied in detail. The optimum condition of preparing the novel latex is that the amount of emulsifier is 8.0% (wt %) and the mass ratio of SDBS to OP-10 is 2 : 1 and the mass ratio of main monomer VAc to VeoVa10 is 3 : 1. The amount of initiator is 0.8% and the amounts of HFMA and BZMA are 6.0 and 8.0% (wt %), respectively. Results indicate that the water resistance of the latex film and thermal stability are improved when the fluorine and BZMA monomers are added.
研究领域:
高分子化学
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材料科学
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应用化学
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功能材料
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纳米材料
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 11
·2000075
·
IF 2.335
Rui Feng,Suyun Jie,Pierre Braunstein,Bo-Geng Li
(Thio)urea/base systems have been widely used in the ring-opening polymerization (ROP) of lactones based on their superior performance in activity and selectivity. Herein, a pyridyl-urea ( 6C-PU )/7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene catalytic system is used to prepare the polyesters with cyclic topology via the ROP of lactones in the absence of initiator under solvent-free conditions. The catalytic system shows high activity in the ROP of δ-valerolactone (δ-VL) and cyclic polyvalerolactones (PVLs) with high molecular weights and narrow molecular weight distribution are obtained despite the existence of some linear products generated during the precipitation process. The structure of the resulting polymers is determined by proton and carbon nuclear magnetic resonance spectra, matrix assisted laser desorption/ionization time of flight mass spectrometry, and intrinsic viscosity studies. A possible mechanism is proposed on the basis of NMR analysis and characteristics of polymerization. Thermal and mechanical properties of cyclic PVLs are investigated through differential scanning calorimetry, thermogravimetric analysis, and tensile test.
研究领域:
材料科学
·
有机化学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Chunhong Li,Hang Xiao,Xianfeng Wang,Tao Zhao
The energy consumption and environment pollution play an important role to the sustainable development in the dyeing and finishing industry. The aim of this study is to synthesize a series of acrylated epoxidized soybean oil based UV-curable polyurethane pigment adhesives and to reduce the consumption of energy and environment pollution in pigment printing process. The chemical composition was evaluated using fourier transform infrared spectra and nuclear magnetic resonance hydrogen spectroscopy. The thermal properties of UV-cured films were discussed by thermalgravimetric analysis (TGA) and differential scanning calorimetry (DSC). In addition, the effects of AESO content on particle size, water swelling properties and contact angles of the emulsions and films were investigated. Furthermore, the color yield, the rubbing fastness and washing fastness of the printed fabrics with acrylated epoxidized soybean oil based UV-curable polyurethane as adhesive were evaluated. The application of vegetable oil-based urethane acrylate pigments of cotton fabrics is a cleaner method that can reduce the consumption of energy and environment pollution. Compared to conventional thermally curable coatings, the UV-curable vegetable oil-based urethane acrylate pigment prints adhesive does not require a large amount of water and energy, indicating that vegetable oil-based urethane acrylate pigments have potential application in the cleaner production of textile industry .
研究领域:
纺织化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
STARCH-STARKE
·
2019
·
IF 1.795
Wei Meng,Fangping Chen,Chenhao Zhang,Ruihua Cui,Peilei Wang,Changsheng Liu
In this study, a high-efficiency polyurethane prepolymer (PUP) compatibilizer is developed to improve the compatibility between cassava starch and poly(butylene adipate-co-terephthalate) with higher molecular weight (MPBAT). Preferentially, modified starch (MS) is prepared by reacting isocyanate groups of PUP with hydroxyl groups of starch in a high-speed mixer, and then starch-based MPBAT composites (MSPT) with PUP as a compatibilizer are continuously extruded using twin-screw extruder. The mechanical properties, water absorption, and thermodynamic properties as well as morphology of MSPT are investigated with different PUP contents and at the same mass ratio of MPBAT to starch (1:1). Samples of MSPT-2 provide satisfactory mechanical properties comparable to control samples. Addition of 13 wt.% PUP to MSPT, improves tensile strength from 3.8 to 11.9 MPa and increases elongation at break from 93.3 to 580.4% at room temperature compared with control without the PUP. The hydrophobicity and thermostability properties of MSPT-2 composites are also enhanced. The results further prove that MSPT-2 composites possess excellent compatibility, not only because of the urethane bonds of the PUP and starch, but also stemming from the physical crosslinking between soft segment of PUP and aliphatic segment of MPBAT. Starch-based MPBAT composites with excellent compatibility and high toughness will help broaden the application field of biodegradable plastics.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2020
·Vol. 77
·期 4
·2129-2141
·
IF 3.75
Li-Sha Bai,Jing-Jing Xu,Cai-Xia Zhao,Ya-Li Chang,Yan-Ling Dong,Kai-Ge Zhang,Yong-Qiang Li,Yi-Ping Li,Zhi-Qing Ma,Xi-Li Liu
BACKGROUND Carboxylesterase (CarE) is a major class of enzyme involved in the detoxification of toxic xenobiotics in various insect species. Previous work has shown that the carboxylesterase gene CarE001G found in Helicoverpa armigera is more active and can metabolize synthesized pyrethroids, such as β -cypermethrin, one of the commonly used commercial insecticides for lepidopteran pest control. In addition, CarE001G is very special as it has a very specific glycine-rich region located adjacent to its C-terminal. But whether mutations in this unique sequence can change the biochemistry and function of CarE001G are unknown. RESULTS In this study, four variants of CarE001G with different deletions in the glycine-rich region were obtained and functionally expressed in Escherichia coli . The recombinant proteins were purified and confirmed by Western blot and mass spectrometry analyses. These mutant enzymes showed high catalytic efficiency toward the model substrate α -naphthyl acetate. Inhibition study showed that β -cypermethrin had relatively strong inhibition on CarE activities. In vitro metabolism assay showed that the mutant enzymes significantly enhanced their metabolic activities toward β -cypermethrin with specific activities between 4.0 and 5.6 nmol L -1 min −1 mg −1 protein. Molecular docking analyses consistently demonstrated that deletion mutations in the glycine-rich region may facilitate the anchoring of the β -cypermethrin molecule in the active binding pocket of the mutant enzymes. CONCLUSION The data show that deletion mutations can cause qualitative change in the capacity of CarEs in the detoxification of β -cypermethrin. This indicates that deletion mutations in the glycine-rich region may have the potential to cause synthesized pyrethroid (SP) resistance in H. armigera in the future. © 2020 Society of Chemical Industry
研究领域:
昆虫学
·
分子生物学
·
农药毒理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Wang Jun,Zhu Tianlong,Deng Ziwen,Liu Haicheng,Huang Chunxiang,Li Na,Sun Xueni,Shao Hui,Qi Lv
Isobaric vapour-liquid equilibrium (VLE) data for binary systems containing methyl chloroacetate (MC) + methyl 2-chloropropionate (M2C), MC + methyl dichloroacetate (MDC), and M2C + MDC at 101.33 kPa and the saturated vapour pressure data of these components were measured by using a modified Othmer still. The VLE data showed that these binary systems were all slightly positive deviation solutions compared with the ideal system. Herington area and point tests were used to confirm the thermodynamic consistency for these binary systems, and the results showed good thermodynamic consistency. The interaction energy ( E inter ) between these components was calculated by molecular simulation to explain the normal boiling point and VLE behavior. The simulation results showed weak hydrogen bonds between these chlorinated esters. In addition, the binary VLE experimental data were correlated by the Wilson, NRTL, and UNIQAC models. The correlated results agreed well with the experimental values.
研究领域:
化学工程
·
物理化学
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产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2021
·Vol. 33
·期 4
·1100-1108
·
IF 3.665
Kaiqi Li,Xiliang Liu,Long Chen,Zuochun Xiong,Chengdong Xiong,Dongliang Chen
Amino-functionalized six-membered cyclic carbonate 5-((2-nitrobenzyl) amino)-1,3-dioxan-2-one (NBAC) was synthesized with 2-nitrobenzyl group as photolabile protecting group. The following copolymerization was carried out by using l -lactide as comonomer and Sn (Oct) 2 as catalyst. The amino-functionalized polymer P(LA- co -AC) was obtained by ultraviolet irradiation of P(LA- co -NBAC) to remove the protecting group. The structures of products were confirmed by 1 H nuclear magnetic resonance (NMR) and 13 C NMR analysis. The pendant amino groups not only resulted in an enhancement of the hydrophilicity, but also played a role of antibacterial effect due to the positive charge imparted to the material.
研究领域:
材料科学
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生物医学工程
·
有机化学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2023
·
IF 5
Xu Pan,Wei Bai,Jinfang Liu,Wenfu Zhang,Xuefeng Sheng,Yang Zhou,Jianfu Zhang
Acrylate-modified aqueous polyurethane has become a widely used material due to its good physical and versatile chemical properties. However, owing to damage resulting from daily use, which often limits polymer performance, it is important to prepare a transparent and repairable polyurethane material. In this work, an acrylate-modified aqueous polyurethane based on the reversible structure of oxime–carbamate of butanedione oxime (POU) was prepared. The visible-light transmittance of the POU film could exceed 70%; its tensile strength and elongation at break could reach 3.0 MPa and 493%, respectively, and the POU film had a tensile strength of 3.9 MPa and elongation at break of 589% after repair. In addition, the POU has adjustable fluorescence properties, which makes this material suitable for potential application in the field of information encryption.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）