接枝位置异构的笼型两亲性分子的自组装模拟  

Dissipative Particle Dynamics Simulation of Self-assembly of Regio-isomeric Cage-type Amphiphiles in Bulk

作　　者：徐明虎 宋青亮 刘美娇 Ming-hu Xu;Qing-liang Song;Mei-jiao Liu(Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang Province,School of Chemistry and Chemical Engineering,Zhejiang Sci-Tech University,Hangzhou 310018;State Key Laboratory of Molecular Engineering of Polymers,Department of Macromolecular Science,Fudan University,Shanghai 200433)

机构地区：[1]浙江省高分子材料表面与界面科学重点实验室、浙江理工大学化学与化工学院,杭州310018 [2]复旦大学聚合物分子工程国家重点实验室、复旦大学高分子科学系,上海200433

出　　处：《高分子学报》2024年第10期1405-1413,共9页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号22373086、22303017)资助项目

摘　　要：利用耗散粒子动力学(DPD)方法模拟了接枝在笼型分子不同顶点的双链分子形成的邻、间和对3种位置异构体的自组装行为.研究结果表明,随着接枝链长增加,3种位置异构体的自组装结构的相序列和稳定相区间有显著区别,接枝链长较短时,尾链聚集的有序结构的曲率以邻、间、对位的顺序依次升高;而接枝链较长时,不同异构体中笼型分子会堆砌成不同的双连续结构.模拟结果还预测到,3种位置异构体的有序-无序相转变温度(T_(ODT))按照邻、间、对的顺序降低,且3种位置异构的两两组合异构体系的T_(ODT)也符合该变化规律;这些相行为的差异可以从分子链的堆积方式的微观角度来理解.该研究证实了微小的结构单元的差异可以对自组装结果产生深远的影响,从而为探索软物质体系的非常规的自组装结构提供了新的思路.The self-assembly behavior of three regio-isomers,namely the ortho-,meta-,and para-isomers,formed by double chains grafted at different vertices of cage-like molecules,was simulated using the dissipative particle dynamics(DPD)method.The results indicate that a long the varying length of the grafting chains the three regioisomers exhibit inconsistent regulation of the emergence and stability of self-assembled structures.Specifically,when the grafting chains are relatively short,the curvature of the ordered structures self-assembled by the tail chains increases in the order of ortho-,meta-,and para-isomer.In contrast,when the grafting chains are longer,the cage-like molecules in different isomers tend to stack into distinct bicontinuous structures.The simulation results also predict that the temperature of the order-disorder transition(T_(ODT))for the three regio-isomers decreases in the order of ortho-,meta-,and para-,and this trend is consistent with the T_(ODT) of the combined regio-isomers.The diverse phase behaviors in the regio-isomers can be understood from the different conformation of the chains and packing of the cage molecules.This study clarifies that the tiny differences in the structural unit can profoundly impact the self-assembled structures,which offers new insights into exploring unconventional order structures self-assembled in soft matters.

关 键 词：笼型分子 嵌段共聚物 耗散粒子动力学 自组装 

分 类 号：O641.3[理学—物理化学]