Block and Star-Block Copolymers by Mechanism Transformation. 3. S-(PTHF-PSt)4 and S-(PTHF-PSt-PMMA)4 from Living CROP to ATRP
Block and Star-Block Copolymers by Mechanism Transformation. 3. S-(PTHF-PSt)4 and S-(PTHF-PSt-PMMA)4 from Living CROP to ATRP
复制标题
DOI：
10.1021/ma991736n
复制
发表时间：
2000-06
期刊：
影响因子：
5.5
通讯作者：
Xu Yijin;C. Pan
中科院分区：
文献类型：
--
作者：
Xu Yijin;C. Pan
以四氢呋喃为原料，采用阳离子开环活性聚合法制备星形聚四氢呋喃四醇酯，并与溴乙酰基和溴异丁基氯进行酯化反应。用合成的中间体作为宏观引发剂，以CuBr/2,2′-联吡啶为催化剂，在80 ~ 110℃下引发苯乙烯原子转移自由基聚合（ATRP）和甲基丙烯酸甲酯原子转移自由基聚合（ATRP）。动力学研究和GPC分析提供了“活”聚合的证据：活性物质浓度恒定，分子量分布窄，分子量控制良好。核磁共振谱和GPC分析证实了四臂星形聚合物和共聚物的形成：S-(PTHF)4、S-(PTHF- pst)4和S-(PTHF- pst - pmma)4。对于S-(PTHF-PSt)4，通过对共聚物水解得到的PSt进行GPC分析进一步证实了这一结论。
Star-shaped poly(tetrahydrofuran) tetrols were prepared by living cationic ring-opening polymerization of tetrahydrofuran and esterified with bromoacetyl and bromoisobutyryl chloride. The intermediate produced was used as macroinitiator to initiate the atom transfer radical polymerization (ATRP) of styrene and subsequently atom transfer radical polymerization of methyl methacrylate at 80−110 °C with CuBr/2,2‘-bipyridine as catalyst. Kinetic studies and GPC analyses provided the evidences of “living” polymerization: constant concentration of active species, narrow molecular weight distribution, and well control of molecular weight. The NMR spectra and GPC analyses demonstrated the formations of four-armed star polymer and copolymers: S-(PTHF)4, S-(PTHF-PSt)4, and S-(PTHF-PSt-PMMA)4. For S-(PTHF-PSt)4, this conclusion was further confirmed by GPC analysis of the PSt obtained from hydrolysis of the copolymer.