CAJ | 학술논문

以八甲基环四硅氧烷（D4）、苯基三（二甲基硅氧烷基）硅烷（PTDMS，俗称三氢封头剂）或四（二甲基硅氧基）硅烷（TDMS，俗称四氢封头剂）为原料，通过开环聚合法合成了三端氢基聚硅氧烷（PDMS-H3）和四端氢基聚硅氧烷（PDMS-H4）；再将其与甲基丙烯酸叔丁酯（t-BMA）在氯铂酸-四氢呋喃（THF）溶液催化下通过硅氢加成反应得到三端酯基聚硅氧烷（PDMS-t-BMA3）和四端酯基聚硅氧烷（PDMS-t-BMA4）；最后在浓硫酸催化下水解制得三端羧基聚硅氧烷（PDMS-COOH3）和四端羧基聚硅氧烷（PDMS-COOH4）。采用FT-IR、1 H NMR和GPC对各阶段产物的结构和摩尔质量及其分布进行表征。结果表明，通过开环聚合、硅氢加成、酸性水解三步反应能够获得结构清晰、摩尔质量可控的多臂端羧基聚硅氧烷，且叔丁酯基聚硅氧烷酸性水解反应效率高，后处理简单，对硅氧烷主链的影响较小。
이팔갑기배사규양완（D4）、분기삼（이갑기규양완기）규완（PTDMS，속칭삼경봉두제）혹사（이갑기규양기）규완（TDMS，속칭사경봉두제）위원료，통과개배취합법합성료삼단경기취규양완（PDMS-H3）화사단경기취규양완（PDMS-H4）；재장기여갑기병희산숙정지（t-BMA）재록박산-사경부남（THF）용액최화하통과규경가성반응득도삼단지기취규양완（PDMS-t-BMA3）화사단지기취규양완（PDMS-t-BMA4）；최후재농류산최화하수해제득삼단최기취규양완（PDMS-COOH3）화사단최기취규양완（PDMS-COOH4）。채용FT-IR、1 H NMR화GPC대각계단산물적결구화마이질량급기분포진행표정。결과표명，통과개배취합、규경가성、산성수해삼보반응능구획득결구청석、마이질량가공적다비단최기취규양완，차숙정지기취규양완산성수해반응효솔고，후처리간단，대규양완주련적영향교소。
With octamethylcyclotetrasiloxane (D4 ),tris (dimethylsiloxy) phenylsilane (PTDMS ) or tetrakis (dimethylsiloxy)-silane (TDMS )as raw materials,hydrogen terminated polydimethylsilox-anes (PDMS-Hx,x=3,4)were synthesized via ring-opening polymerization.Then tert-butyl methacry-late (t-BMA)was grafted to PDMS-Hx via hydrosilylation to prepare ester terminated polydimethylsilox-anes (PDMS-t-BMAx,x=3,4)with H2PtCl6 as catalyst,and the multi-branched carboxyl terminated polydimethylsiloxanes (PDMS-COOHx,x=3,4)were prepared by subsequent hydrolysis reaction under acid.The structures and molecular weights of the products were characterized by FT-IR,1 H NMR and GPC.Results show that multi-branched carboxyl terminated polydimethylsiloxanes with certain structures and molecular weights can be synthesized under control via a three-step procedure:ring-opening polymeri-zation,hydrosilylation reaction and acid hydrolysis reaction.The acid hydrolysis of polydimethylsiloxanes with a tertiary-butyl ester group has advantages of high efficiency,simple after-treatment and less influ-ence on siloxane backbone.