有机硅改性有机合成树脂的研究状况

有机硅聚合物具有优异的耐候性、耐玷污性和耐高低温性,高度的疏水性,良好的透气性等被广泛应用.各种有机合成树脂有各自的优点和缺点,它们的缺点正好是有机硅聚合物的优点.将有机硅引入有机合成树脂,利用有机硅优点改进有机合成树脂的不足,使有机硅和有机合成树脂的性能更加完善,这对有机硅和有机合成树脂工业发展具有重大的意义.因此有机硅改性有机树脂是近年来研究的热点.本文简单综述了几种有机硅化学改性有机合成树脂的性能特点、制备方法及研究发展状况.     

有机硅改性UV固化水性环氧树脂的研究

以环氧树脂E-51、甲基三乙氧基硅烷为原料,用接枝共聚的方法合成了有机硅改性水溶性UV固化环氧树脂,该方法有效地改善了环氧树脂的柔韧性、水溶解性,提高了成膜物的机械性能,其拉伸强度达到53.5 MPa,断裂伸长率为46.5%,耐冲击性大于50 kg/cm。通过红外光谱、热重分析表征产物的结构和性能,结果表明,有机硅已经成功接枝到环氧树脂的分子上。有机硅改性后环氧树脂在400℃的分解率由之前的60%降至40%。文章同时讨论了有机硅改性水性UV固化环氧树脂合成中反应温度、有机硅种类以及加入量等对UV固化水性环氧树脂成膜物的附着力、耐水性及耐碱性的影响,以此获得最佳反应条件:质量分数为14.4%的甲基三乙氧基硅烷与羧酸改性的环氧树脂在90℃下反应5～6 h。     

反应性乳化剂对有机硅-丙烯酸酯乳液共聚合的影响

有机硅改性丙烯酸酯;乳液聚合;反应性乳化剂对有机硅-丙烯酸酯乳液共聚合的影响     

多乙烯基硅油改性丙烯酸酯乳液的合成及性能

以自制阳离子型乳化剂H、多乙烯基硅油和丙烯酸类单体为主要原料,采用一步法和半连续种子乳液聚合法合成有机硅改性丙烯酸酯乳液。研究了不同聚合方法、不同有机硅含量对硅丙乳液乳胶膜的吸水率、疏水性能的影响,通过纳米粒度-Zeta电位分析仪、接触角仪、红外光谱、透射电镜对乳液及聚合物结构进行了表征。结果表明有机硅单体参与了聚合,乳液稳定性好、平均粒径小。采用半连续种子乳液聚合法合成乳液,有机硅最大添加量为40%(占壳层单体总量),乳胶膜的吸水率只有3.2%,对水的接触角达到105.2o。     

室温交联型硅丙微胶乳的合成研究Ⅲ.聚合工艺对聚合稳定性及胶膜性能的影响

采用两种聚合工艺(种子微乳液聚合法和单体预乳化法)分别合成了室温交联型有机硅改性丙烯酸酯聚合物微胶乳，研完了不同工艺条件对聚合稳定性、乳胶粒径和胶膜的结构性能的影响．     

种子乳液聚合方法制备聚苯乙烯－聚硅氧烷核壳粒子

采用种子乳液聚合的方法，制备以聚苯乙烯为壳、聚有机硅氧烷为核的弹性粒子，探讨了加料和引发方式对粒子的结构及形貌的影响，并对苯乙烯种子乳液聚合的机理进行了初步的讨论。     

水性含氟聚氨酯的研究进展

水性含氟聚氨酯具有低的VOC排放,同时由于氟元素的引入,解决了传统水性聚氨酯耐水、耐油性差的缺点,大大拓展了其在涂料、皮革、油墨等领域的应用范围,因此受到广泛关注.本文综述了近年来国内外水性含氟聚氨酯的主要研究进展,综合比较了两种合成水性含氟聚氨酯主要方法,即核壳乳液聚合法和缩聚共聚法的各自特点,并对由两种不同方法制备的水性含氟聚氨的性能进行了讨论.     

有机硅改性丙烯酸酯乳液的合成

乳液聚合;涂料;有机硅改性丙烯酸酯乳液的合成     

化学接枝改进ZnO-有机硅纳米复合材料的光学性能

采用N-(三甲氧基硅丙基)-4-叠氮-2,3,5,6-四氟苯甲酰胺(PFPA-silane)改性纳米氧化锌,并将PFPA-silane接枝在有机硅聚合物链上.接枝反应改变了纳米复合物的折光指数,并使ZnO纳米粒子与有机硅基体的折光指数更加匹配.这减少了纳米氧化锌粒子对光的散射作用,增加了纳米ZnO-有机硅纳米复合物的透明性.所制备的复合物通过接枝改性后透光率最多可提高50%.研究结果表明无机物和聚合物的折光指数的匹配程度可以通过偶联剂与聚合物基体的反应来进行调控.     

含C60聚苯乙烯微球的制备及光电导性能研究

目前,多功能、高性能聚合物微球的合成及应用已成为研究热点.制备聚合物微球的方法有乳液聚合法、分散聚合法、无皂乳液聚合法、超微乳液聚合法和悬浮聚合法等.制备微米级微球通常采用乳液聚合法和分散聚合法.     

环氧树脂水性化体系研究进展

系统地介绍了目前国内外环氧树脂水性化的研究进展,总结了环氧树脂水性化体系的特点与应用,并提出一种水性环氧树脂乳液制备的新方法。     

The wettability of polymer films depends on the polymerization conditions

The polymerization conditions have a strong influence on the properties and time-dependent behavior of a sessile water drop on polymer films. For a given copolymer composition, the recipe components of emulsion copolymer films clearly influence the initial static water contact angle. Common emulsifiers such as sodium dodecyl sulfate lead to lower contact angles than poly(ionic liquid) dispersions which are a new class of stabilizers for emulsion polymerization. In contrast to the static contact angle, the time-dependent properties of the water contact angle reflect the particular conditions during the polymerization. It is a general conclusion of this study that waterborne emulsion copolymers show a distinctly different time-dependent behavior of the contact angle than bulk polymers of the same molecular composition regardless of the initial static contact angle.     

无皂相反转乳化法制备高分子水基分散体系

高分子树脂水基分散体系是指高分子树脂以微粒形式分散于水中 ,包括高分子乳液、高分子悬浮液等体系 .由于高分子树脂水基分散体系具有低成本 ,高性能 ,无污染等优点 ,一直受到普遍关注 .高分子树脂乳液一般通过乳液聚合制备 .该方法只适用于由含双键的单体制备的加聚产物 .而在制备缩聚产物的乳液时 ,乳液聚合方法局限性很大 ,而最近发展起来的相反转乳化技术 ,适用于制备包括加聚产物和缩聚产物在内的大多数高分子水基分散体系 ,拓宽了高聚物水基分散体系的范围 [1] .杨振忠等 [2～ 5] 利用相反转乳化技术制备了未固化和可固化的环氧树脂…     

双组分水性环氧树脂涂料

简述了双组分水性环氧树脂涂料的特点及其用途，分别介绍了水性环氧树脂乳液和水性环氧固化剂的制备方法、双组分水性环氧树脂涂料的分类、混合体系的固化成膜机理和适用期的判断。最后给出了对水性环氧树脂涂料进行配方设计时应考虑的因素。     

有机硅改性苯丙乳液的研究进展

综述了有机硅改性苯丙乳液的机理、方法和聚合技术研究进展.介绍了物理共混法和化学改性法,重点阐述了化学改性法的最新研究进展,并展望了有机硅改性苯丙乳液的发展趋势.     

自乳化水性环氧树脂乳液的研制

利用化学改性的方法制备自乳化型水性环氧树脂乳液。采用二乙醇胺部分开环环氧树脂,并采用聚醚多胺进行扩链,制备可自分散的阳离子水性环氧树脂乳液。本文研究了乳液研制时共溶剂丙二醇甲醚、环氧树脂分子量、二乙醇胺用量、不同的聚醚多胺、聚醚多胺D-230用量、HAC用量对乳液稳定性的影响。并对乳液性能进行测试,结果表明,该乳液具有良好的贮存稳定性,VOC含量低,涂膜综合性能优良等特点,该乳液为环保型产品。     

主链掺杂氧原子聚硅烷的研究进展

介绍了一类新型有机硅聚合物主链掺杂氧原子聚硅烷的合成与性质.该类聚合物是通过氧原子有规律地插入聚硅烷主链,形成具有氧杂低聚硅烷的序列结构(-[(SiMe2)mO]n-).聚合物的主链呈现了聚硅烷以及聚硅氧烷的杂化体结构.通过对此类聚合物性质的研究,能够获得有关此类聚合物行为的知识,从而进一步促进人们对聚硅烷和聚硅氧烷化学性质的了解.总结了此类聚合物的两类有效合成方法:通过α,ω-二功能基封端的线性硅烷低聚体缩聚反应法以及氧杂环硅烷单体的开环聚合反应法,包括氧杂环硅烷单体的开环聚合平衡和反应机理.讨论了此类聚合物的表征、热稳定性及其结构形态.在结论部分展望了此类聚合物的预期应用前景.     

Silicone‐based impact modifiers for poly(vinyl chloride), engineering resins,and blends

Silicone‐based impact modifiers were prepared in a previous study. The modifiers were composed of silicone/acrylic rubber cores and grafted acrylic shells. They improved the toughness of poly(vinyl chloride) (PVC) and poly(methyl methacrylate). The silicone emulsion that was used to produce the silicone‐based impact modifiers was prepared via two routes: emulsion polymerization and bulk polymerization of octamethyltetracyclosiloxane. Many silicone‐based impact modifiers were produced that had different silicone/acrylic rubber characteristics. Through a toughness examination of modified PVC, the best composition of the silicone‐based impact modifiers was obtained, and the silicone content in the rubber composition was 25 wt %. The morphology of the silicone‐based impact modifiers, determined by transmission electron microscopy, was as follows: core and second shell polymers were mainly poly(butyl acrylate), and the first shell polymer was silicone. The silicone‐based impact modifiers were blended with engineering resins such as PVC, polycarbonate (PC), poly(butylene terephthalate) (PBT), and PC/PBT mixtures. The impact strength under standard conditions and after weathering test conditions for blends of the silicone‐based impact modifiers were investigated with respect to two commercially available acrylic and methyl methacrylate/butadiene/styrene impact modifiers. The results showed good weatherability and good toughness under low‐temperature conditions for the silicone‐based impact modifiers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1112–1119, 2004     

A novel approach to graft acrylates onto commercial silicones for release film fabrications by two-step emulsion synthesis

In this study, a two-step emulsion polymerization method was specially designed so as to effectively graft acrylate monomers onto commercial silicones and improve the properties of release films. FT-IR, DSC and grafting ratio tests showed that the grafting reaction happened and a high grafting ratio can be achieved when the silicone content was more than 20%. According to SEM-EDX result, the “sea-island” structure on the surface of release films made by acrylate-modified silicone latexes was proven. The silicones formed the continuous “sea” structure and the grafted acrylate polymers formed the segregated “island” structure. The carbon and silicon distributions were not uniform through the cross-section of release films made by acrylate-modified silicone latexes. After acrylate modification, the surface tension of silicone release films increased from 19-21 mN/m (before acrylate modification) to 30 mN/m and the release force increased from 8.1 g/in. to 47 g/in. As a result, the properties of release films have been effectively improved by our novel method for advanced applications.     

PREPARATION AND STUDY ON SILICONE ACRYLATE MICRO-EMULSION OF MULTIPOLYMER

1. INTRODUCTION The silicone acrylate emulsion with excellent weather resistance, contamination resistance and water resistance is applied widely. The majority of silicone acrylate emulsion is ordinary emulsion, larger particle size. If the particle size of emulsion is larger, the compactability and smoothness of its film formation becomes more defective. The micro-emulsion is a kind of emulsion with 10~100nm particle size, transparent or semitransparent disperse system with favorabl…