Ultrafast Form Ⅱ to Ⅰ Transition of Isotactic Polybutene-1  

作　　者：Xing Qiu Umair Azhar Jing-Qing Li Ding-Hai Huang Shi-Chun Jiang 

机构地区：[1]School of Materials Science and Engineering, Tianjin University

出　　处：《Chinese Journal of Polymer Science》2019年第7期633-636,共4页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 51673147, 51573131, and 21374077)

摘　　要：Isotactic polybutene-1 (iPB-1) is a semi-crystalline polymer with polymorph and puzzled structural transitions. The stable form I of iPB-1 with excellent physical and mechanical properties can hardly be obtained directly from the melt;instead, metastable form II will spontaneously and slowly transform into form I. Bypassing the unstable form II formation is of great significance in polymer processing, which inspires extensive research on seeking the pathways to direct formation of form I. Methods for accelerating form II to I transition are another main focus in terms of practical approach for directly obtaining form I. Taking advantage of the solvent, an ultrafast transition of iPB-1 from form II to I within minutes has been achieved at room temperature. Such an ultrafast transition is detected after treating with dichloromethane (DCM) at 30 ℃, though the framework of isothermally crystalized iPB-1 spherulite morphology could not be fully modified. The ultrafast II-I transition of iPB-1 is attributed to the solvent-induced packed-mesophase and temperature-selected chain conformation adjustment.This ultrafast transition would shed light on understanding the mechanisms of polymorphic transitions in iPB-1.Isotactic polybutene-1(i PB-1) is a semi-crystalline polymer with polymorph and puzzled structural transitions. The stable form I of i PB-1 with excellent physical and mechanical properties can hardly be obtained directly from the melt; instead, metastable form II will spontaneously and slowly transform into form I. Bypassing the unstable form II formation is of great significance in polymer processing, which inspires extensive research on seeking the pathways to direct formation of form I. Methods for accelerating form II to I transition are another main focus in terms of practical approach for directly obtaining form I. Taking advantage of the solvent, an ultrafast transition of i PB-1 from form II to I within minutes has been achieved at room temperature. Such an ultrafast transition is detected after treating with dichloromethane(DCM) at 30 °C, though the framework of isothermally crystalized i PB-1 spherulite morphology could not be fully modified. The ultrafast II-I transition of i PB-1 is attributed to the solvent-induced packed-mesophase and temperature-selected chain conformation adjustment.This ultrafast transition would shed light on understanding the mechanisms of polymorphic transitions in i PB-1.

关 键 词：POLYBUTENE-1 ULTRAFAST TRANSITION MESOPHASE CONFORMATION 

分 类 号：O6[理学—化学]