Effect of microstructure on chain flexibility and glass transition temperature of polybenzofulvene
Effect of microstructure on chain flexibility and glass transition temperature of polybenzofulvene
复制标题
微观结构对聚苯并富烯链柔韧性和玻璃化转变温度的影响
DOI：
10.1016/j.polymer.2020.123276
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发表时间：
2021
期刊：
影响因子：
4.6
通讯作者：
Mays Jimmy
中科院分区：
文献类型：
--
作者：
Wang Huiqun;Wang Weiyu;Lu Wei;Osa Masashi;Kang Nam-Goo;Hong Kunlun;Mays Jimmy
聚苯并呋喃（PBF）是一种具有非常高的玻璃化转变温度（tg）的聚二烯，这使其成为高温热塑性弹性体应用的潜在候选者。已知聚二烯的T g与链的柔韧性有关。然而，尚未有研究报道将链柔韧性与PBF的微观结构联系起来。在此，我们研究了具有窄分子量分散和1,2 -添加范围从23%到99%的线性PBFs的溶液性质。在不同条件下，采用阴离子活性聚合法制备了该材料。具体而言，通过使用三检测器尺寸排除色谱（SEC）结合测量特征粘度和分子量，研究了由Flory特征比C∞定义的链柔韧性以及链柔韧性对微观结构的依赖。采用触头虫状链模型估计了其持续长度（l p）和链径（d B）。据我们所知，PBF的特征比是迄今所报道的所有聚二烯中最高的。
Polybenzofulvene (PBF) is a polydiene with a very high glass transition temperature (T g), which makes it a potential candidate for use as the hard block for high-temperature thermoplastic elastomer applications. The T g s of polydienes are known to be related to chain flexibility. However, no studies have been reported that correlate the chain flexibility to the microstructure of PBF. Herein, we present a study of solution properties of linear PBFs with narrow molacular weight dispersity and having 1, 2-addition ranging from 23% to 99%. The materials were prepared by living anionic polymerization under different conditions. Specifically, the chain flexibility as defined by the Flory's characteristic ratio, C∞, and dependence of chain flexibility on microstructure by combined measurements of intrinsic viscosity and molecular weight using triple-detector size exclusion chromatography (SEC) is studied. The persistence lengths (l p) and chain diameters (d B) were also estimated using the touched-bead wormlike chain model. To the best of our knowledge, the characteristic ratio of PBF is found to be the highest of all polydienes that have been reported so far.