Two techniques of coating water-swellable polymer latexes (hydrogels) with an inorganic or organic layer were developed, based on interfacial polymerization. The hydrogel latexes were prepared by inverse suspension polymerization. The first kind of interfacial polymerization is hydrolysis and polycondensation of tetraethyl orthosilicate (TEOS) or 3-(trimethoxysilyl)propylmethacrylate (TMS-PMA) on the surface of hydrogel latexes. The hydrochloric acid, which is the catalyst for this reaction, was previously loaded into the hydrogel latexes. The HCl-containing hydrogel latexes were then suspended in an organic solution of TEOS or TMS-PMA. The hydrolysis and condensation occur only at the surface of each hydrogel particle and the generated SiO2 or SiO(PMA) network covers the hydrogel latexes. The second interfacial polymerization is polymerization of methylenedi-p-phenyl diisocyanate (MDI) and triethylene glycol (TEG) on the surface of hydrogel latexes. TEG was deposited on the hydrogel by suspending the hydrogel powder in a tetrahydrofuran (THF) solution of TEG and evaporating the THF. The TEG-deposited hydrogel powder was then suspended in an organic solution containing both MDI and the catalyst dibutyltin dilaurate (DBTL). The MDI and DBTL molecules react with the TEG molecules only at the surface of the hydrogel particles, and the polyurethane P(MDI-TEG) thus formed wraps the particles. Based on these two coating procedures, three kinds of materials were obtained: SiO2 coated hydrogels, SiO-(PMA) coated hydrogels and P(MDI-TEG) coated hydrogels. Soft polyether brushes were grafted to the SiO-(PAM) coated latexes. The P(MDI-TEG) coated hydrogels were used as reservoirs for beta-hydroethyltheophylline (beta-HETP), and the release of the latter molecules from the coated hydrogels was investigated. (C) 1995 John Wiley and Sons, Inc. [References: 10]
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机译：基于界面聚合，开发了两种用无机或有机层涂覆水溶胀性聚合物胶乳（水凝胶）的技术。通过逆悬浮聚合制备水凝胶胶乳。第一种界面聚合是原硅酸四乙酯（TEOS）或甲基丙烯酸3-（三甲氧基甲硅烷基）丙酯（TMS-PMA）的水解和缩聚。预先将作为该反应的催化剂的盐酸装入水凝胶胶乳中。然后将含HCl的水凝胶胶乳悬浮在TEOS或TMS-PMA的有机溶液中。水解和缩合仅发生在每个水凝胶颗粒的表面，并且生成的SiO2或SiO（PMA）网络覆盖了水凝胶胶乳。第二种界面聚合是在水凝胶胶乳表面上的亚甲基二对苯基二异氰酸酯（MDI）和三甘醇（TEG）的聚合。通过将水凝胶粉末悬浮在TEG的四氢呋喃（THF）溶液中并蒸发THF，将TEG沉积在水凝胶上。然后将沉积了TEG的水凝胶粉末悬浮在同时包含MDI和催化剂二月桂酸二丁基锡（DBTL）的有机溶液中。 MDI和DBTL分子仅在水凝胶颗粒表面与TEG分子反应，因此形成的聚氨酯P（MDI-TEG）包裹了颗粒。基于这两种涂覆程序，获得了三种材料：SiO2涂覆的水凝胶，SiO-（PMA）涂覆的水凝胶和P（MDI-TEG）涂覆的水凝胶。将软聚醚刷接枝到SiO-（PAM）涂覆的乳胶上。将P（MDI-TEG）包被的水凝胶用作β-氢乙基茶碱（β-HETP）的储库，并研究了后者分子从包被的水凝胶中的释放。 （C）1995 John Wiley and Sons，Inc. [参考：10]
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