共查询到18条相似文献,搜索用时 82 毫秒
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以角鲨烯作为天然橡胶的模型物合成了ATRP引发剂,即先通过双键的部分环氧化得到环氧化角鲨烯(ESq),ESq再与2-溴代异丁酸发生开环反应合成溴功能化角鲨烯(ESq-Br).采用FT-IR和1 H-NMR研究了ESq与ESq-Br的结构,并结合GC-MS和13C-NMR分析了环氧基、溴功能基等官能团的分布情况.结果表明:ESq中含有3种环氧结构,且环氧基是均匀分布的;环氧基开环的同时伴随着重排副反应,通过研究剩余环氧基的分布,可推测ESq-Br中溴功能化单元(即引发点)的分布也是均匀的. 相似文献
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原子转移自由基聚合(ATRP)是一种新型的可控/活性聚合技术,现已广泛应用于聚合物分子结构设计、无机材料表面修饰、蛋白质检测以及生物大分子的分离和杀菌防污等.在此类反应过程中涉及的三大要素:单体、引发体系(引发剂、催化剂、配位剂)及反应介质,其中核心要素为ATRP引发剂,其结构与性质是ATRP反应成败的决定因素之一.本文在综述了小分子引发剂的种类与性质及ATRP的反应机理的基础上,着重综述了近年来官能团反应法、偶联反应法及自由基聚合法制备ATRP大分子引发剂的最新进展.同时还综述了大分子引发剂通过ATRP反应在聚合物结构设计中的应用,以及对无机材料和生物材料的表面修饰的最新进展,最后对ATRP引发体系的未来发展与应用进行了展望. 相似文献
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Chuan Jie Cheng Quan Lei Fu Xiong Xiong Bai Shao Jin Liu Liang Shen Wu Qin Fan Hong Xia Li 《Chemical Papers》2013,67(3):336-341
A novel cationic gemini surfactant has been readily synthesised in 70 % total yield. The functional gemini surfactant can act both as an emulsifier and an atom transfer radical polymerisation (ATRP) initiator in mini-emulsion polymerisation of methyl methacrylate (MMA), in which no other emulsifier was required. 1-(Dimethylamino)dodecane (N,N-dimethyldodecylamine, DMDA) was found to be a good ligand in the activator generated by electron transfer (AGET) ATRP reaction. Kinetic studies indicated that the polymerisation featured controlled/living radical polymerisation. 相似文献
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This study presents styrene emulsion polymerization initiated in aqueous media through an atom transfer radical polymerization (ATRP) mechanism. The water-soluble initiator employed in this process has been synthesized by our team by reacting diethanolamine with α-bromoisobutyryl bromide. The complexation of CuBr was realized by using a bicomponent complexation system comprised of 2,2′-bipyridine and N,N,N′,N′,N″-pentamethyldiethylenetriamine. The initiator ratio influence on the obtained emulsion was studied. The obtained latexes and polymer particles have been characterized by dynamic light scattering, scanning electron microscopy, and gel permeation chromatography. 相似文献
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David S. Spencer Bryan C. Luu David W. Beckman Nicholas A. Peppas 《Journal of polymer science. Part A, Polymer chemistry》2018,56(14):1536-1544
Crosslinked cationic nanoscale networks with hydrophobic cores are an environmentally robust alternative to self‐assembled polymeric drug delivery carriers with respect to therapeutic encapsulation and stability to dilution. However, the ability to tune the degree of PEG incorporated into nanogels during synthesis is more challenging. In this work, biodegradable cationic nanogels were synthesized by ARGET ATRP emulsion polymerization in a single step. The density of PEG in the final nanogels ranged from zero to 40 wt % and was dependent on the feed concentration of PEG monomer, surfactant concentration, surfactant hydrophilic–lipophilic balance, and the ratio of cationic to nonionic surfactant. A comprehensive analysis of nanogel material properties as a function of PEG graft density is presented including analysis of composition, monomer conversion, thermal properties, size, surface charge, and degradation. This study provides a robust analysis for the synthesis of degradable cationic nanogels via a controlled radical polymerization with predictable degrees of PEGylation. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1536–1544 相似文献
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Polytetrafluoroethylene (PTFE)/polyacrylate core-shell nanoparticles were produced via the emulsifier-free seeded emulsion
polymerization of acrylate monomers with PTFE latex as seed. The monomer conversions under different synthesis parameters
were monitored by a gravimetric method. The polymerization conditions for preparing PTFE/polyacrylate core-shell nanoparticles
were surveyed and optimized. The chemical component of the PTFE/polyacrylate particles was confirmed by comparing the Fourier-transform
infrared spectra of PTFE and PTFE/polyacrylate particles. The core-shell structure of the resulting PTFE/polyacrylate nanocomposite
particles was investigated by transmission electron microscopy. The water contact angles of the films prepared from PTFE/polyacrylate
nanocomposite particles showed that the films were hydrophilic, which confirmed that polyacrylate covered the surface of the
PTFE particles. This kind of PTFE/polyacrylate core-shell nanoparticles might advance the compatibility of PTFE with other
materials due to the covering of the polyacrylate shell on the surface of PTFE, which would make them promising in various
fields. 相似文献
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Stoffelbach F Griffete N Bui C Charleux B 《Chemical communications (Cambridge, England)》2008,(39):4807-4809
This communication describes the first example of the efficient use of a simple amphiphilic molecule as both a surfactant and an initiator in the miniemulsion polymerization of methyl methacrylate under AGET and ARGET ATRP conditions. 相似文献
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The synthesis of poly(methyl acrylate)-block-poly(gamma-benzyl-L-glutamate) (PMA-b-PBLG) diblock copolymers, using atom-transfer radical polymerization (ATRP) of methyl acrylate and living polymerization of gamma-benzyl-L-glutamate-N-carboxyanhydride (Glu-NCA) is described. Amido-amidate nickelacycle end groups were incorporated onto amino-terminated poly(methyl acrylates), and the resulting complexes were successfully used as macroinitiators for the growth of polypeptide segments. This method allows the controlled preparation of polypeptide-block-poly(methyl acrylate) diblock architectures with control over polypeptide chain length and without the formation of homopolypeptide contaminants. 相似文献
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Initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) of acrylonitrile was first conducted at various ambient temperatures (30-45 ℃). The key to success is ascribed to the usage of an appropriate low temperature radical initiator (2,2'-azobis(2,4-dimethylvaleronitrile)) and a high reactivity catalytic system (CuBr2/Me6TREN). The molar ratio of Cu catalyst tO AN as low as 1:20000 wa.s used to prepare well-defined polyacrylonitrile with controlled molecular weight and a narrow polydispersity index range of 1.08-1.30, while the monomer conversion was up to ca. 98%. The apparent activation energy of the polymerization was calculated to be 128.45 kJ/mol, suggesting that the polymerization strongly depended on reaction temperature. The very high chain-end functionality of the resultant polymer was confirmed by ^1H-NMR and GPC analyses as well as chain extension reaction. 相似文献
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The hydrophobic monomer dodecafluoroheptyl methacrylate has been copolymerized with hydrophilic monomer methacrylic acid in aqueous solution without any additional emulsifier used via a two-step polymerization process of RAFT. The FTIR and GPC results indicated that amphiphilic copolymers with a narrow molecular weight distribution and well-defined blocks have been synthesized successfully. And the copolymers are likely to form steady micelles in the emulsion. Indicated by TEM, it is clear that micelles with a diameter of 70-120 nm have been formed. Despite a content of 22 wt% of hydrophilic carboxyl, films formed by casting the emulsion onto the baseplate can be hydrophobic after heating treatment. 相似文献