含活性硅氧烷型大分子改性剂BA-MMA-VTES的合成与表征

针对弱极性天然/丁苯橡胶复合体系,从分子设计的角度出发,选择乙烯基三乙氧基硅氧烷(VTES)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)为单体,通过自由基溶液聚合并优化了反应条件:在85℃和115℃分别加入两种不同量的引发剂BPO和DCP,均保温反应2h,合成了三元共聚物BA-MMA-VTES大分子表面改性剂,用于纳米碳化硅、氮化硅陶瓷粉体的表面改性。采用FTIR、NMR、GPC、DSC、TGA等对所合成的三元共聚物的结构、性质和数均相对分子质量进行了分析和表征。通过FTIR、NMR测试结果,证实了BA-MMA-VTES三元共聚物的结构;通过GPC测试,证明BA-MMA-VTES三元共聚物的数均相对分子质量控制在3000～10000;DSC显示合成的大分子只有一个Tg,在3.3℃左右,表明它是无规共聚物,柔性适中;TGA显示三元共聚物主要热分解区间在280～500℃,热稳定性良好。

Synthesis and Characterization of Macromolecular Modifier BA-MMA-VTES with Active Triethoxysilane

In this work,a new macromolecular modifier butyl acrylate-methyl methacrylate-vinyltriethoxysilane(BA-MMA-VTES tercopolymer)was synthesized via radical polymerization under optimum conditions adopting BPO and DCP as initiators.The modifier was used for surface modification of nano-sized ceramic material powders and designed for weak polarity natural rubber/styrene-butadiene rubber(NR/SBR)system.The structure and properties were systematically investigated by FTIR,NMR,GPC,TGA and DSC.According to the spectra of FTIR and NMR,it can be inferred that macromolecular tercopolymer has been synthesized.GPC shows that the number average molecular weight is between 3 000～10 000,which is optimum for modifier.DSC and TGA show that there is only one Tg about 3.3 ℃ and the main weight loss is between 280 and 500 ℃,indicating that it is a random tercopolymer with good stability.