Crystalline Regio-/Stereoregular Glycine-Bearing Polymers from ROMP: Effect of Microstructures on Materials Performances
Crystalline Regio-/Stereoregular Glycine-Bearing Polymers from ROMP: Effect of Microstructures on Materials Performances
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ROMP 结晶区域/立构规整甘氨酸聚合物：微观结构对材料性能的影响
DOI：
10.1021/acs.macromol.6b02244
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发表时间：
2016-12-27
期刊：
影响因子：
5.5
通讯作者：
Wang, Xianhong
中科院分区：
文献类型：
--
作者：
Li, Maosheng;Cui, Fengchao;Wang, Xianhong
与具有精确控制微观结构的天然生物聚合物（如蛋白质和DNA）相比，合成具有控制微观结构的氨基酸或多肽聚合物仍然是聚合物化学领域的一个长期挑战。本文设计并合成了一系列新的甘氨酸取代环烯单体。用Grubbs第二代催化剂对所有3取代单体进行开环复分解聚合（ROMP），可获得具有高头尾区域规整性和高反式立体规整性的含甘氨酸聚合物，而5取代单体的ROMP既不具有区域选择性，也不具有立体选择性。理论研究表明，在聚合过程中，3位上的立体笨重的甘氨酸取代基对高区域化学和立体化学是至关重要的。重要的是，差示扫描量热法和广角x射线散射测量表明，不饱和3-取代聚合物由于其高度的结构规整性和较强的化学性质，是半结晶的。
Synthesis of amino acid or peptide-bearing polymers with controlled microstructures is still a long-going challenge in polymer chemistry in contrast to natural biopolymers with exactly controlled microstructures like proteins and DNA. Here, a series of new glycine-substituted cyclooctenes monomers were designed and synthesized. Ring-opening metathesis polymerizations (ROMP) of all 3-substituted monomers with Grubbs second-generation catalyst afford glycine-bearing polymers with high head-to-tail regioregularity and high trans-stereoregularity, whereas ROMP of 5-substituted monomers is neither regio- nor stereoselective. Theoretical study revealed that sterically cumbersome glycine substituent in the 3-position is crucial for the high regio- and stereochemistry in the polymerization. Of importance, differential scanning calorimetry and wide-angle X-ray scattering measurements show that unsaturated 3-substituted polymers are semicrystalline due to their high degrees of structure regularity and the strong hy...