有机硅-丙烯酸酯共聚乳液的合成研究

采用半连续预乳化核壳乳液聚合工艺合成了有机硅改性共聚乳液，研究了影响乳液性能的几种因素。FTIR谱图分析表明，共聚过程中，有机硅氧烷已经接枝到丙烯酸酯聚合物分子链上，并且改变了共聚树脂的性能。     

SBR-St-MMA核壳乳液接枝共聚颗粒特性

考察了SBR-St-MMA核壳乳液接枝共聚过程中乳胶粒形态、大小及分布的变化。研究了引发剂的种类及用量、乳化剂的用量、硫醇的用量对最终核壳乳液接枝聚合物胶乳粒径的影响。探讨了本核壳乳液接枝共聚过程中,乳胶粒径分布变化不大的原因。     

有机硅-丙烯酸酯共聚乳液

华南理工大学的柯跃虎等人以甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸、有机硅单体等为原料,采用半连续乳化乳液聚合工艺,合成出核壳结构的有机硅改性共聚乳液。在有机硅单体用量5 %、引发剂用量0 6%、核壳中乳化剂配比1∶2、反应温度80℃的条件下合成的乳液性能最佳。FTIR谱图分析表明,有机硅单体在聚合过程中已接枝成为共聚物的一部分,有机硅单体的引入明显地改善了乳液的诸多性能有机硅-丙烯酸酯共聚乳液     

核-壳型有机硅改性丙烯酸酯乳液的研制

采用种子乳液聚合法，以BA为壳，MMA为核，MAA、HEMA和有机硅氧烷为官能性单体，合成了内硬外软的核－壳型有机硅改性丙烯酸酯乳液。讨论了官能性单体、核－壳单体结构、乳化剂、引发剂等对乳液性能的影响。     

丙烯酸酯接枝共聚改性聚氨酯乳液的结构与性能

采用原位接枝聚合制备核壳结构的丙烯酸酯改性聚氨酯乳液。用电子显微镜测定了乳液粒子的大小和形态。DSC和TG谱图特征，以及耐水性和耐溶剂性研究证实丙烯酸酯在聚氨酯链上接枝共聚。改性聚氨酯乳液的热稳定性、耐水性和耐溶剂性明显提高。     

丙烯酸酯改性聚氨酯乳液的研究进展

介绍了丙烯酸酯改性聚氨酯乳液的物理掺混、嵌段共聚、核壳共聚、接枝共聚和互穿网络共聚等方法。并且结合实验对各种改性方法的优、缺点进行了说明。     

聚丙烯酸酯改性聚氨酯乳液的研究进展

综述了聚丙烯酸酯改性聚氨酯乳液的物理掺混法、嵌段共聚法、核壳共聚法、接枝共聚法和互穿聚合物网络共聚法的研究进展,并且结合实验对各种改性方法的优、缺点进行了讨论.     

PBA/MMA-MAA核-壳型乳液聚合研究

本文以种子乳液聚合法制备了PBA／MMA－MAA核－壳型复合取合物乳液。讨论了复合聚合物时引发剂用量和补加乳化剂用量对聚合反应及乳胶粒及其分布的影响。结果表明，引发剂用量控制在0．2％（wt)，乳化剂用量在0．75％（wt)，可制得粒径分布较窄且性能良好的核－壳型聚合物乳液用于毛面剂中。     

丙烯酸类单体改性水性聚氨酯的研究进展

对丙烯酸类单体改性水性聚氨酯的各种方法进行了归纳分类,主要介绍了对水性聚氨酯膜改性的接枝改性法及对水性聚氨酯乳液改性的物理共混法、嵌段共聚法、核-壳乳液共聚法和互穿聚合物网络聚合法.     

氧化还原引发核/壳乳液的制备及其在水性涂料中的应用

采用过硫酸盐－亚铁盐氧化还原引发体系合成具有核／壳结构的苯乙烯－丙烯酸酯乳液，通过对比不同引发体系乳液粒径粒径分布，玻璃化转变温度，乳液成膜性能等指标，表明氧化还原引发的核／壳结构的苯丙乳液性能比热引发无规共聚苯丙乳液大大提高，用此乳液配制的涂料性能也有很大提高。通过选择增稠剂及添加助剂，解决了涂料调色过程中浮色及分层现象。     

新型核-壳结构醋丙乳液的合成及性能

采用2阶段方法合成了高亲水单体含量的核-壳结构醋丙乳液,第1阶段以水溶性引发剂过硫酸钾为引发剂合成了核,第2阶段以油溶性引发剂偶氮二异丁腈在核表面引发聚合成壳。并对乳液形貌、结构及膜的性能进行了表征。结果表明,该法合成的乳液具有凝胶率低、稳定、力学性能好等特点。     

Novel Core–Shell of Polymethyl Methacrylate/butyl Acrylate/vinyl Silica Nanocomposite Particles through Seed Emulsion Polymerization

A new core–shell structure of polymethyl methacrylate/butyl acrylate copolymer/vinyl silica nanocomposite was successfully prepared in aqueous solution through seed emulsion polymerization. Vinyl-functionalized silica nanoparticles were synthesized using sol–gel technique of triethoxyvinylsilane in aqueous solution. New established covalent bond between the vinyl groups located on the surface of vinyl-functionalized silica nanoparticles and vinyl group of monomers and the encapsulation into methyl methacrylate/butyl acrylate copolymer through seed emulsion polymerization process. The prepared core–shell latex polymers were characterized by Fourier transform infrared, UV–vis, thermal analyses, tensile strength, elongation at break, field emission scanning electron microscope, transmission electron microscope, and zeta potential. The tensile strength improved by introducing vinyl silica into the matrix up to 5%, which proved the reinforcing role of vinyl silica in the matrix of polymer.     

核壳型醋丙乳液胶黏剂的制备及其性能研究

乳胶粒子形态控制是聚合物乳液研究的重要领域,几十年中在聚合物材料、涂料、胶黏剂等诸多领域的成功的应用使得核壳结构聚合物复合粒子备受关注。采用种子乳液聚合法,采用复配乳化剂体系合成了以醋酸乙烯酯为核,醋酸乙烯酯和丙烯酸丁酯为壳的乳液,并重点研究了单体滴加速率、SDS与OP-10质量比、引发剂用量对乳液性能的影响,通过透射电镜和红外光谱仪表征了乳胶粒子核壳结构的存在。     

ACR中壳层PMMA相对分子质量对PVC／ACR共混物性能的影响

采用种子乳液法制备了核壳型聚丙烯酸酯(ACR),并分别采用十二烷基硫醇和正辛基硫醇作为链转移剂对 ACR壳层的聚甲基丙烯酸甲酯(PMMA)进行相对分子质量调节,并用于PVC共混改性。黏度法对PMMA的相对分子质量测定表明,正辛基硫醇的相对分子质量调节能力较强。采用差示扫描量热分析测定PMMA的玻璃化转变温度(Tg),并对共混树脂进行动态力学性能测试。当ACR壳层PMMA平均相对分子质量低于12×104时,PVC/ACR 共混树脂的缺口冲击强度大大提高。与纯PVC相比,共混树脂的Tg均略有提高,其增量随ACR壳层PMMA平均相对分子质量的降低而减小。动态力学性能测试结果表明,ACR壳层聚合物平均相对分子质量越低,共混物分子链段运动活化能提高越少。     

氯乙烯/丙烯酸酯二元及多元共聚物的研究进展

介绍了氯乙烯/丙烯酸酯多元共聚物、聚氯乙烯树脂/丙烯酸酯/顺丁烯二酰亚胺接枝共聚物、聚氯乙烯树脂/N-取代马来酸胺/丙烯酸酯接枝共聚树脂、氯乙烯/乙酸乙烯/丙烯酸羟丙酯共聚物、氯乙烯/乙酸乙烯/丙烯酸丁酯共聚乳液、聚丙烯酸酯-氯乙烯接枝共聚物、氯乙烯/乙烯/丙烯酸羟乙酯共聚涂料树脂、氯乙烯/丙烯酸甲酯共聚乳液的特点、生产工艺及其性能和用途.     

Preparation of polystyrene/poly(vinyl acetate) nanocomposites with a core–shell structure via emulsifier‐free emulsion polymerization

Polystyrene/poly(vinyl acetate) latex nanoparticles with a core–shell morphology in an emulsifier‐free emulsion polymerization system were prepared with purified styrene and vinyl acetate (VAc) as monomers and 2,2′‐azo bis(2‐amino propane) dihydrochloride (ABA,2HCl) as the initiator and emulsifier. The optimized conditions of polymerization of VAc, on top of the already‐formed polystyrene as a core polymer, with a core–shell morphology were obtained using various parameters such as volume ratio of the first and second stages, type of process, and reaction time. The morphologic structure of the nanoparticles was studied by scanning electron microscopy and transmission electron microscopy. The latex nanoparticles and polymers were characterized by differential scanning calorimetry. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2409–2414, 2006     

The toughness and morphology of (chlorinated poly[vinyl chloride])/(methyl methacrylate‐butadiene‐styrene) blends

A series of methyl methacrylate‐butadiene‐styrene (MBS) graft copolymers were synthesized via seeded emulsion polymerization techniques by grafting styrene and methyl methacrylate on poly(butadiene‐co‐styrene) (SBR) particles. The chlorinated poly(vinyl chloride) (CPVC)/MBS blends were obtained by melting MBS graft copolymers with CPVC resin, and the effect of the core/shell ratio of MBS graft copolymer and SBR content of CPVC/MBS blends on the mechanical properties and morphology of CPVC/MBS blends was studied. The results showed that, with the increase in the core/shell ratio, the impact strength of the blend increased and then decreased. It was found that, when the core/shell ratio was 50/50, the impact strength was about 155 J/m, and the tensile strength evidently increased. The toughness of the CPVC/MBS blend was closely related to the SBR content of the blend, and with the increasing of SBR content of blend, the impact strength of the blend increased. The morphology of CPVC/MBS blends was observed via scanning electron microscopy. Scanning electron microscopy indicated that the toughness of CPVC/MBS blend was consistence with the dispersion of MBS graft copolymers in the CPVC matrix. J. VINYL ADDIT. TECHNOL., 22:501–505, 2016. © 2015 Society of Plastics Engineers     

乙烯基硅氧烷改性丙烯酸酯乳液聚合的动力学及成核机理分析

用种子乳液聚合法研究了硅氧烷改性丙烯酸酯的乳液聚合,对影响种子乳液聚合动力学的因素进行讨论,并分析了乳液聚合的成核机理.实验结果表明：反应温度、引发剂浓度、乳化剂浓度和有机硅氧烷用量对有机硅改性丙烯酸酯乳液聚合动力学有较大的影响.反应温度越高,引发剂浓度越高、乳化剂浓度越高、有机硅氧烷用量相对较小,乳液聚合反应的转化率越高;此外,体系的pH值在6～8之间时也有利于反应的进行.种子乳液聚合中R_P∝［E］^0.72,R_P∝［I］^0.56,表观活化能E_a为143.92 kJ•mol^-1.种子乳液聚合初期,反应主要是单体液滴成核;进入壳层反应时,反应成核主要是以胶束成核为主.     

Preparation and characterization of composite resin by vinyl chloride grafted onto poly(BA-EHA)/poly(MMA-St)

Crosslinked poly(butyl acrylate-co-2-ethylhexyl acrylate)/poly(methyl methacrylate-co-styrene) (ACR I) latex was synthesized by multi-stage emulsion polymerization. A series of grafting vinyl chloride (VC) composite latices were prepared by emulsion copolymerization in the presence of core-shell ACR I latex. The effects of ACR I amount and its core/shell ratio on particle diameters of the composite latices and mechanical properties of the prepared materials were investigated. The grafting efficiency (GE) of VC grafted onto ACR I increases with an increasing ACR I content. Transmission electron microscope (TEM) study indicates that ACR I latex particles have a regular core-shell structure obviously. However, when styrene content in the shell of ACR I is more than 70 percent of the shell by weight, ACR I latex particles have an irregular core-shell morphology like sandwich. The composite latex particles synthesized by core-shell ACR I latex grafting VC have a clear three-layered core-shell structure. Dynamic mechanical analysis (DMA) study reveals that the compatibility between ACR I and PVC is well improved. With increasing ACR I content, the loss peak in low temperature range for every composite sample becomes stronger and stronger and gradually shifts to a higher temperature. Scanning electron microscope (SEM) graphs showed that the fractured surface of the composite sample exhibited better toughness of the material. TEM graphs showed that ACR I was uniformly dispersed in the PVC matrix.     

Effect of ethyleneglycol dimethacrylate crosslinker on the performance of core‐double shell structure poly(vinyl acetate‐butyl acrylate) emulsion

Core‐double shell structure poly(vinyl acetate‐butyl acrylate) emulsion was prepared by semicontinuous emulsion polymerization, and the effects of ethyleneglycol dimethacrylate crosslinker (EGDMA) on the emulsion particle structure and film performance were studied systematically. The emulsion particles' structure was characterized by transmission electron microscopy and Fourier transform infrared spectroscopy, and the particle size and distribution were characterized by Zeta potential—particle analyzer, as well as analysis of the film mechanical properties, water resistance, thermal properties, and so on. The results show that, when 0.1 and 0.5% EGDMA were added to the inner‐shell and outer‐shell reaction stage under the core‐double shell P(VAc‐BA) emulsion preparation process, respectively, it led to a more clear core‐double shell structure and a larger particle size (about 500–800 nm) of emulsion particles, and the comprehensive performance of the P(VAc‐BA) emulsion showed better. This work provided some insight into modifying the surface properties of the emulsion particles, which may expand the application field of the emulsion. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41899.