Synthesis of stereoblock poly(methyl methacrylate) via transformation of isotactic‐specific living polymer anion to syndiotactic‐specific anion
Synthesis of stereoblock poly(methyl methacrylate) via transformation of isotactic‐specific living polymer anion to syndiotactic‐specific anion
复制标题
通过等规特异性活性聚合物阴离子转化为间规特异性阴离子合成立构嵌段聚（甲基丙烯酸甲酯）
DOI：
10.1002/pi.1994.210330207
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发表时间：
1994
影响因子：
3.2
通讯作者：
K. Hatada
中科院分区：
文献类型：
--
作者：
T. Kitayama;N. Fujimoto;T. Yanagida;K. Hatada
甲基丙烯酸甲酯（MMA）在三烷基铝（R3 Al; R = CH 3、C2 H5和n-C4 H9）存在下，在−78°C下，通过全同立构聚甲基丙烯酸甲酯（PMMA）活性阴离子（由t-C4 H9 MgBr在甲苯中于−60°C制备）进行聚合，得到立构嵌段PMMA，即全同立构PMMA-嵌段-间同立构PMMA。在R3 Al中，（CH 3）3Al最有效地得到具有窄分子量分布的立体嵌段PMMA。当Al/Mg比≥ 6时，间规PMMA嵌段中rr三联体的含量达到76%左右。该方法还用于制备由全同立构PMMA嵌段和间同立构甲基丙烯酸丁酯嵌段组成的立构嵌段共聚物。研究了立构嵌段PMMA的立体复合物形成和溶液粘度。
Polymerization of methyl methacrylate (MMA) by isotactic poly(methyl methacrylate) (PMMA) living anion, prepared with t-C4H9MgBr in toluene at −60°C, was carried out at −78°C in the presence of trialkylaluminiums (R3Al; R = CH3, C2H5, and n-C4H9) to obtain a stereoblock PMMA, isotactic PMMA-block-syndiotactic PMMA. Among the R3Als, (CH3)3Al gave most effectively the steroblock PMMA with narrow molecular weight distribution. The fraction of rr triad in the syndiotactic PMMA block increased with increase in the ratio of Al/Mg and reached about 76% at a ratio of Al/Mg ≥ 6. The method was also used to prepare stereoblock copolymer comprising isotactic PMMA block and syndiotactic block of butyl methacrylate. Stereocomplex formation and solution viscosity of the stereoblock PMMA were also studied.