Liu Jing, Wang Hsiang-Ching, Su Chean-Cheng, Yang Cheng-Fu
School of Information Engineering, Jimei University, Xiamen 361021, China.
Department of Chemical and Materials Engineering, National University of Kaohsiung, No. 700, Kaohsiung University Rd., Nan-Tzu Dist., Kaohsiung 811, Taiwan.
Materials (Basel). 2018 Sep 9;11(9):1667. doi: 10.3390/ma11091667.
An immiscible blend of poly(hydroxy ether of bisphenol-A) (phenoxy) and poly(1,4-butylene terephthalate) (PBT) with phase separation was observed in as-blended samples. The compatibilization of phenoxy/PBT blends can be promoted through chemical exchange reactions of phenoxy with PBT upon annealing. The annealed phenoxy/PBT blends had a homogeneous phase with a single that could be enhanced by annealing at 260 °C. Infrared (IR) spectroscopy demonstrated that phase homogenization could be promoted by annealing the phenoxy/PBT blend, where alcoholytic exchange occurred between the dangling hydroxyl group (⁻OH) in phenoxy and the carbonyl group (C=O) in PBT in the heated blends. The alcoholysis reaction changed the aromatic linkages to aliphatic linkages in the carbonyl groups, which initially led to the formation of a graft copolymer of phenoxy and PBT with an aliphatic/aliphatic carbonyl link. The progressive alcoholysis reaction resulted in the transformation of the initial homopolymers into block copolymers and finally into random copolymers, which promoted phase compatibilization in blends of phenoxy with PBT. As the amount of copolymers increased upon annealing, the crystallization of PBT was inhibited by alcoholytic exchange in the blends.
在共混样品中观察到聚（双酚 A 羟基醚）（苯氧基）和聚（1,4 - 丁二醇对苯二甲酸酯）（PBT）的不相容共混物存在相分离现象。通过退火时苯氧基与 PBT 的化学交换反应可促进苯氧基/PBT 共混物的增容。退火后的苯氧基/PBT 共混物具有均相结构，且在 260℃退火可增强这一结构。红外（IR）光谱表明，对苯氧基/PBT 共混物进行退火可促进相均匀化，在加热的共混物中，苯氧基中悬垂的羟基（⁻OH）与 PBT 中的羰基（C=O）之间发生醇解交换。醇解反应将羰基中的芳族键转变为脂肪族键，最初导致形成具有脂肪族/脂肪族羰基键的苯氧基和 PBT 的接枝共聚物。渐进的醇解反应导致初始均聚物转变为嵌段共聚物，最终转变为无规共聚物，这促进了苯氧基与 PBT 共混物中的相增容。随着退火后共聚物数量的增加，共混物中的醇解交换抑制了 PBT 的结晶。
