有限长高分子链特征标度对溶剂性质的依赖性  

Solvent-dependence of the characteristic scaling exponent for single polymer chain with finite length

作　　者：张双双 苗兵 所同川 ZHANG Shuangshuang;MIAO Bing;SUO Tongchuan(Department of Physics,Beijing Normal University,Belting 100875,China;College of Materials Science and Opto-Electronie Technology,University of Chinese Academy of Sciences,Beifing 100049,China;College of Pharmaceutical Engineering of Traditional Chinese Medicine,Tianfin University of Traditional Chinese Medicine,Tianfin 300193,China)

机构地区：[1]北京师范大学物理系,北京100875 [2]中国科学院大学材料科学与光电技术学院,北京100049 [3]天津中医药大学中药制药工程学院,天津300193

出　　处：《中国科学院大学学报（中英文）》2018年第5期602-606,共5页Journal of University of Chinese Academy of Sciences

基　　金：国家自然科学基金(21604064)资助

摘　　要：采用自洽平均场理论并结合蒙特卡洛方法考查不同溶剂中高分子单链回转半径与聚合度的标度关系。计算结果表明,在Θ溶剂中标度指数ν≈0.495,说明此时高分子链遵循理想链的行为;另一方面,在良溶剂中标度指数ν并非普适常数,而是随着溶剂性质的变化而改变,并且总是明显低于经典理论预测值0.6。分析指出,有限链长效应是造成这一偏差的重要原因。We employ the self-consistent field theory（ SCFT） with the help of Monte Carlo technique to study the scaling behavior of the radius of gyration Rgof a single polymer chain with respect to the chain length N. The numerical results indicate the scaling exponent ν≈0. 495 for Θ-solvent,which is a typical ideal chain behavior. However,for good solvent cases,the ν value displays explicit dependence on the solvent quality and is always lower than the classical prediction of 0. 6. We argue that such a discrepancy is mainly attributed to the finite chain length effect.

关 键 词：高分子单链 回转半径 标度指数 自洽平均场理论 蒙特卡洛方法 

分 类 号：O631.1[理学—高分子化学]