Block copolymers of γ-methacryloxypropyltrimethoxysilane and methyl methacrylate by RAFT polymerization.: A new class of polymeric precursors for the sol-gel process
Block copolymers of γ-methacryloxypropyltrimethoxysilane and methyl methacrylate by RAFT polymerization.: A new class of polymeric precursors for the sol-gel process
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DOI：
10.1021/ma048143j
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发表时间：
2005-03-08
期刊：
影响因子：
5.5
通讯作者：
D'Agosto, F
中科院分区：
文献类型：
--
作者：
Mellon, W;Rinaldi, D;D'Agosto, F
以2,2′-偶氮异丁腈（AIBN）为引发剂，研究了2-氰丙基-2-基二硫苯甲酸酯（CPDB）介导的反应性单体γ -甲基丙氧基丙基三甲氧基硅烷（gamma mamps）在二氧六环中的可逆加成-裂解链转移（RAFT）聚合。优化了聚合温度为80℃的条件，合成了具有低多分散性指数（PDI < 1.3）的可控gammamps链（最高M-n = 40000 g mol(-1)）。基质辅助激光解吸电离飞行时间（MALDI-ToF）质谱分析表明，虽然二硫苯甲酸酯链端发生了降解，但得到了预期的结构。从gammaMPS （Mn = 32 100 g mol(-1), PDI = 1.16， PMMA校准）或PMMA嵌段（m = 21000 g mol(-1), PDI = 1.14）开始，合成基于gammaMPS和甲基丙烯酸甲酯（MMA）的嵌段共聚物。嵌段共聚的成功体现在嵌段共聚前后的粒径排除层析（SEC）色谱向更高摩尔质量的转变。P（MMA-b-gammaMPS）的质子核磁共振分析允许计算出gammamps块的摩尔质量（17 400 g mol-(1)），与目标块（18 150 g mol(-1)）一致。
Reversible addition-fragmentation chain transfer (RAFT) polymerization of the reactive monomer gamma-methacryloxypropyltrimethoxysilane (gammaMPS) mediated by 2-cyanoprop-2-yl dithiobenzoate (CPDB) has been studied in dioxane using 2,2'-azobis(isobutyronitrile) (AIBN) as initiator. Conditions were optimized for a polymerization temperature of 80 degreesC, and controlled PgammaMPS chains (up to M-n = 40 000 g mol(-1)) exhibiting low polydispersity indexes (PDI < 1.3) were synthesized. Their characterization by matrix-assisted laser desorption ionization time-of-flight (MALDI-ToF) mass spectrometry showed that the expected structure was obtained although degradation of the dithiobenzoate chain end occurred. Syntheses of block copolymers based on gammaMPS and methyl methacrylate (MMA) were performed starting from either the PgammaMPS (Mn = 32 100 g mol(-1), PDI = 1.16, PMMA calibration) or the PMMA block (M. = 21000 g mol(-1), PDI = 1.14). The success of the block copolymerization was showed by the shift toward higher molar mass of the size exclusion chromatography (SEC) chromatograms recorded before and after block copolymerization. Proton NMR analyses of P(MMA-b-gammaMPS) allowed to calculate the molar mass of the PgammaMPS blocks (17 400 g mol-(1)) which agreed with the targeted one (18 150 g mol(-1)).