JOURNAL OF MATERIALS SCIENCE
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2019
·Vol. 55
·期 5
·1946-1958
·
IF 3.442
Mi Xue,Wang Xingrui,Gao Chunjuan,Su Weijun,Zhang Yuying,Tan Xiaoyue,Gao Jianping,Liu Yu
Polystyrene with π -conjugated end groups (BPS) synthesized by reversible addition–fragmentation transfer polymerization was used to modify the surface of reduced graphene oxide (rGO) sheets through π – π stacking (BPS–rGO) in order to increase their hydrophobicity and dispersibility. The modification of rGO makes it possible for BPS–rGO to stabilize Pickering w/o (water-in-oil) emulsions of small droplets, in which toluene is taken as the continuous phase and distilled water as the dispersed phase. The effects of the BPS–rGO concentration and the water/oil ratio on the Pickering emulsions were investigated. The results indicate that increasing hydrophobicity of BPS–rGO was favorable to forming stable w/o emulsions and the emulsion stability was increased with the increase in the BPS–rGO concentration or with the decrease in water/oil ratio. Using BPS–rGO to stabilize Pickering w/o emulsions is an effective and versatile approach to fabricate active materials that can be employed as catalysts for chemical reactions.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
MACROMOLECULES
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2022
·
IF 6.057
Chengliang Wang,Xu Zhang,Wei Zhao,Xin Liu,Qingfu Wang,Jingjiang Sun
Hyperbranched aliphatic polycarbonates (HBPCs) have attracted significant attention in the field of biomedical application owing to their abundant end groups, biocompatibility, and nontoxic degradation products. However, their practical application is hampered by tedious synthesis procedures. The present work described a novel organo-catalyzed “A1+B2”-ring-opening polymerization (ROP) using a monofunctional primary alcohol (A1) as an initiator and a bicyclic carbonate monomer (B2) for the straightforward synthesis of HBPCs under mild conditions. No gelation was observed up to 90% conversion of the cyclic carbonate ring. HBPCs with molar masses in the range from 7 to 20 kg/mol were obtained. Based on the “A1+B2”-ROP, HBPCs bearing a variety of functionalities including alkene, alkyne, aldehyde, furan, azide, and mPEG groups, which are of great significance in the field of click chemistry, have been successfully prepared by using functional alcoholic initiators. This polymerization strategy allowed for precise control over the HBPC structure: (1) the hyperbranched polymer (HBP) backbone can be adjusted by design of a bicyclic carbonate monomer with various linkages; (2) the use of an appropriate initiator leads to the introduction of functional end groups. Overall, the “A1+B2”-ROP provides an efficient method for preparing a variety of HBPs like hyperbranched polyester, polyether, polyphosphate, and poly(amino acid) with complex architectures in a single step.
研究领域:
材料科学
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生物医学工程
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高分子化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Rongxiang Hu,Fenghua Zhang,Lan Luo,Linlin Wang,Yanju Liu,Jinsong Leng
Shape memory polymers (SMPs) with elevated switching temperatures and enduring thermal properties are highly desirable yet challenging in certain aerospace applications. In this study, high-temperature shape memory phthalonitrile resins (SMPNs) were developed using an end-capping strategy with the uniphthalonitrile (UPN) as the end-capping reagent to modulate the density of the cross-linked network. The resultant SMPNs exhibit a glass transition temperature (Tg) at approximately 300 °C, with a shape fixation rate of about 98 % and a shape recovery rate around 97 %. Importantly, these SMPNs also demonstrated exceptional thermal stability, with a thermal decomposition temperature exceeding 445 °C. Additionally, an oxyacetylene ablative test revealed the SMPNs' robust ablative resistance, as the linear ablation rate remained below 0.1 mm/s and the mass ablation rate was less than 0.1 g/s. The commendable shape memory performance and superior high-temperature resistance allowed the SMPNs to successfully undergo the shape recovery process when subjected to a butane flame. Furthermore, after a high-temperature annealing process, the SMPNs exhibited electrical conductivity due to graphitization, even possessing wave-absorbing properties within a specific frequency range. It is foreseeable that these multifunctional SMPNs will have extensive applications in the aerospace sector, given the advancement of smart structures.
研究领域:
材料科学
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航空航天工程
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2016
·
IF 2.632
Jingcheng Liu,Kuan Wang,Licheng Lin,Ren Liu,Yazhen Xie,Fei Gao,Xiaoya Liu
The fluorinated polyimides with double bond end groups (G-FPIs) based on 4,4′-(hexafluoroisopropylidene) diphthalic anhydride, 4,4′-(hexafluoroisopropylidene) dianiline, 4-aminobenzoic acid and glycidyl methacrylate were synthesized via a typical two-step imidization method. The structure and properties of G-FPIs were characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance ( 1 HNMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It was determined that all G-FPIs were the amorphous phase and easily soluble in many polar organic solvents, and the G-FPIs had high glass-transition temperature ( T g ). Then, UV-curable coatings were prepared from G-FPIs, and the properties were evaluated by real-time fourier transform infrared (RTIR), thermogravimetric analysis (TGA), UV–vis spectroscopy, water contact angle and water absorption test. Results showed that these coatings possessed favorable double bond conversion, excellent thermal stability, higher optical transparency and lower moisture uptakes. Moreover, the coatings exhibited good hardness and excellent gloss. Due to the outstanding combination properties, these UV-cured coatings based on G-FPIs could be considered as potential candidates for photoelectric, microelectronic and aerospace materials.
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
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2016
·Vol. 54
·期 15
·2413-2420
·
IF 3.114
Ye Sha,Qing Zhu,Yuanxin Wan,Linling Li,Xiaoliang Wang,Gi Xue,Dongshan Zhou
A new type of chain transfer agent used in reversible addition fragmentation chain transfer (RAFT) polymerization named 9-anthracenylmethyl (4-cyano-4-( N -carbazylcarbodithioate) pentanoate) (ACCP) was synthesized with a total yield over 75% by the incorporation of both fluorescent donor and acceptor chromophores. Polymerization of heterotelechelic α,ω end-labeled dye-functionalized polystyrene (PS), poly(methyl methacrylate) (PMMA), and poly( n -butyl methacrylate) (PBMA) with adjustable molecular weights and narrow polydispersity could be conducted by a one-pot procedure through RAFT polymerization with this bischromophore chain transfer agent. The polymerizations demonstrated “living” controlled characteristics. By taking advantage of the characteristic fluorescence resonance energy transfer (FRET) response between the polymer chain terminals, the variation of chain dimensions in solution from the dilute region to the semidilute region can be monitored by changes in the ratio of the fluorescence intensities of the carbazolyl group to the anthryl group, which lends itself to potential applications in characterizing chain dimensions in solutions for thermodynamic or dynamic studies. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54 , 2413–2420
研究领域:
高分子化学
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物理化学
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
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IF 10.383
Dou Luo,Zhengyan Jiang,Chengwei Shan,Lanqing Li,Chenghao Duan,Qian Liu,Zhaojin Wang,Kai Wang,Baomin Xu,Aung Ko Ko Kyaw
Fine-tuning the alkyl chains and end groups of non-fused ring electron acceptors (NFREAs) plays vital roles in the promotion of charge transfer (CT) and power conversion efficiency (PCE). In this work, we developed a series of A–D–A′–D–A-type NFREAs, which possess the same terminals (A), the cyclopentadithiophene unit (D), and the thieno[3,4-c]pyrrole-4,6-dione (A′). Despite the subtle difference in side chains and halogenated end groups, the six acceptors exhibit a considerable difference in the efficiency and device stability of the organic solar cells (OSCs). Among the molecules, chlorinated NFREAs show a broader light absorption than the fluorinated ones do. Compared with C8C8–4F (1-octylnonyl and fluorination) and C6C4–4Cl (2-butyloctyl and chlorination), C8C8–4Cl (1-octylnonyl and chlorination) exhibits a lower highest occupied molecular orbital level, higher electron mobility, and denser molecular packing. The OSCs based on PM6:C8C8–4Cl yield the best PCE of 14.11%, which is attributed to the faster charge transport, high miscibility, and preferable morphology. Moreover, the PM6:C8C8–4Cl devices retain 91.1% of the initial PCE after being placed in air with 67% relative humidity for 50 days. This work shows that the simultaneous optimization of side chains and end groups facilitates the CT and improves the stability in the OSCs, offering a novel view into the molecular design of A–D–A′–D–A-type NFREAs.
研究领域:
材料科学
·
化学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 3
·e56365
·
IF 2.7
Jingbo Wu,Jianghua Lin,Wenhao Xiao,Ruijie Xu,Caihong Lei
Nucleating agents are crucial for modifying semi-crystalline polymers, but the impact of different end-group structures on crystallization behavior remains unclear. This study synthesized succinic dihydrazide nucleating agents with various end groups (methyl, ethyl, and tert -butyl) for PET composite materials. The tert -butyl-terminated nucleating agent showed the best performance, increasing the crystallization peak temperature to 203.8°C, crystallinity to 27.3%, and reducing half-crystallization time to 2.8 min at 220°C. It also enhanced the impact strength to 47.2 kJ·m −2 and flexural modulus to 2623 MPa, while improving Vicat softening temperature and heat distortion temperature by 41 and 8°C, respectively. The results from FTIR and Raman Spectroscopy indicate that the interactions between the end groups of the nucleating agent and the C H bonds in the PET structure, the π–π interactions between the nucleating agent and the PET molecular structure, as well as the modulation of the PET chain conformation by the nucleating agent, are the primary factors contributing to the enhanced crystallinity of PET. This study provides a new approach for designing efficient nucleating agents for high-performance materials.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Li Xu,Suyun Jie,Zhiyang Bu,Bo-Geng Li
As a telechelic polymer, the primary amine-terminated cis -polybutadiene (AmTPB) has a wide application prospect due to its active hydrogens in both end groups and high cis 1,4-chain structure. In this work, the AmTPB with high cis -1,4 content (>96%) was prepared for the first time by taking cis -polybutadiene as a starting material. Firstly, the aldehyde-terminated polybutadiene (ATPB) in a molecular weight range of 600–8000 g/mol was successfully synthesized by oxidative degradation of epoxidized polybutadiene prepared by reaction-controlled phase-transfer catalysis. After a simple post-processing, the AmTPB was prepared via two steps, i.e. the efficient synthesis of oxime-terminated polybutadiene (OTPB) from ATPB and the subsequent selective reduction of OTPB. The results showed that the high cis 1,4-chain structure of polybutadiene did not change in all the reactions.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2020
·
IF 3.862
Youjun He,Jiming Chen,Irum Rafique,Zaijun Lu
The catechol groups in mussel adhesive proteins exhibit excellent adhesion property to the skin and tissue surfaces. Inspired by catechol groups, the aim of this study is to synthesize the star-shaped polycaprolactone bio-adhesive bearing catechol end-groups (s-PCL 19 -CA 9 ). Firstly, star-shaped polycaprolactone was synthesized through ring-opening polymerization of caprolactone monomers initiated by β-cyclodextrin, and then the s-PCL 19 -CA 9 was obtained through end-group functionalization using succinic anhydride and dopamine. The structure of s-PCL 19 -CA 9 was characterized by 1 H NMR, FTIR, and static light scattering. Adhesive strength measurements demonstrate that the incorporation of multifunctional catechol groups endows the crosslinked s-PCL 19 -CA 9 with an excellent adhesion property (102 ± 10 kPa). The swelling ratio of crosslinked s-PCL 19 -CA 9 is as low as 3.4 ± 0.2% owing to the hydrophobicity of PCL and the crosslinking structures. Besides, the cytotoxicity studies show that s-PCL 19 -CA 9 is noncytotoxic. The TGA measurements indicate that s-PCL 19 -CA 9 possesses a good thermal stability. Therefore, this work provides a new way for developing multifunctional bio-adhesives with excellent adhesion property and low swelling ratio.
研究领域:
材料科学
·
生物医学工程
·
化学
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产品关联
DOI
高影响因子
LIQUID CRYSTALS
·
2021
·
IF 0
Haonan Lin,Shuaifeng Zhang,Moshin Hassan Saeed,Le Zhou,Hongqi Gao,Junyi Huang,Lanying Zhang,Huai Yang,Jiumei Xiao,Yanzi Gao
In this work, the effects of the methacrylate monomers with various end groups (methyl, hydroxyl, epoxy, tetrahydrofuran, cyclohexane, benzene and siloxane) on the morphologies, electro-optical and mechanical properties of polymer dispersed liquid crystal (PDLC) composite films were systematically investigated. The polymer network morphologies of the samples prepared with the monomers butyl methacrylate, tetrahydrofurfuryl methacrylate, cyclohexyl methacrylate or benzyl methacrylate were observed, and interestingly the polymer balls and polymer ball-networks morphologies were formed by introducing the hydroxypropyl methacrylate and glycidyl methacrylate, respectively. Meanwhile, the films obtained the optimal electro-optical properties with low driving voltage (10.7 V), fast response time (5.0 ms). Finally, the largest shearing force of the prepared PDLC composite films was two to three times better than that of the pristine sample with 3-(trimethoxysilyl)propyl methacrylate (TPMA) monomer doping or surface treatment methods. Thus, this work offers a new way to optimise the overall performance of PDLC films for practical applications.
研究领域:
材料科学
·
光学
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产品关联
DOI
DYES AND PIGMENTS
·
2017
·
IF 3.473
Ying Song,Hongyan Yao,Haiwei Tan,Shiyang Zhu,Bo Dong,Shaowei Guan
Three aromatics endcapped hyperbranched polyimides (HBPIs), with triphenylamine derivative (A 3 ) as core, 4,4-(hexafluoroisopropylidene)diphthalic anhydride as B 2 monomer , phthalic anhydride (PA), 1,8-Naphthalic anhydride (NA) and 3,4-perylenedicarboxylic anhydride (PDA) as endcapping reagents are explored as polymer memory materials. All these HBPIs showed excellent solubility in various organic solutions. Tunable memory characteristics from volatile to nonvolatile were obtained by adjusting the endcapping groups. Compared to PA endcapped HBPI, NA and PDA endcapped HBPIs exhibited enhanced nonvolatile memory behaviors with switch voltages low to 0.8 V and 1.0 V, and outstanding thermal stability with 5% weight loss temperatures reaching up to 533 °C and 554 °C, respectively. Such superior performance can be attributed to the introduced polycyclic arenes end-groups, which leads to stronger conjugation intensity, better hole transport ability and higher charge separation stability.
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
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2019
·Vol. 57
·期 13
·1460-1466
·
IF 2.591
Wentong Gao,Jianwei Xu,Pengfei Zuo,Hao Dong,Yiwu Quan,Pengshan Chang
The dynamic chemistry of disulfide bonds has emerged as one of the most powerful tools used for the fabrication of organic compounds and self-healing materials. In this article, a novel aromatic amine-terminated polysulfide oligomer is first synthesized from thiol-terminated polysulfide oligomer and bis(4-aminophenyl) disulfide via disulfide metathesis mechanism. The resulting oligomer is confirmed by FTIR and 1 H NMR spectra and then successfully applied in constructing self-healable polyurea material (A-LP23-I), which combines the advantages of higher strength of polyureas and excellent self-healing ability of polysulfide-based materials. After subjecting to a temperature of 75 °C for 48 h, both the tensile strength and ultimate elongation of A-LP23-I restore to more than 90% of the original values (3.32 MPa and 396%). This study demonstrates a novel strategy for synthesizing aromatic amine-terminated oligomer. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1460–1466
研究领域:
材料科学
·
有机化学
✓ 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）