聚亚甲基链在弹性形变时的链段取向研究  

A Study of Molecular Orientation of Polymethylene Chains

作　　者：章林溪[1] 黄有兴[1] 赵得禄[2] 

机构地区：[1]浙江大学物理系,杭州310028 [2]中国科学院化学研究所分子科学中心,高分子物理实验室,北京100080

出　　处：《高等学校化学学报》2002年第3期511-513,共3页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 98740 2 1);国家重点专项基金 (批准号 :95 -预 -12 ;G19990 64 80 0 )资助

摘　　要：In this paper, molecular orientation behavior of polymethylene chains was investigated on the basis of considering long\|distance interactions by using the enumeration calculation method and the rotational isomeric state(RIS) model. The chain lengths are from \%N\%=12 to \%N=\%24, and the Lennord\|Jennes potential was adopted in the non\|local interaction calculations. The molecular orientation function(Legendre polynomial) may be well expressed as\$\$<P\-2(ζ)>/(λ\+2-λ\+\{-1\})=a(λ\+2-λ\+\{-1\})+b\$\$here\% a\% and\% b\% only depend on the chain length, and decrease with the increase of chain length, especially for \%b\%. In the meantime, we also calculate the Helmholtz free energy change in the process of tensile deformation. Comparisons with Gaussian chains are made, and our results are close to those obtained from the Roe and Krigbaum theory.In this paper, molecular orientation behavior of polymethylene chains was investigated on the basis of considering long\|distance interactions by using the enumeration calculation method and the rotational isomeric state(RIS) model. The chain lengths are from \%N\%=12 to \%N=\%24, and the Lennord\|Jennes potential was adopted in the non\|local interaction calculations. The molecular orientation function(Legendre polynomial) may be well expressed as\$\$<P\-2(ζ)>/(λ\+2-λ\+\{-1\})=a(λ\+2-λ\+\{-1\})+b\$\$here\% a\% and\% b\% only depend on the chain length, and decrease with the increase of chain length, especially for \%b\%. In the meantime, we also calculate the Helmholtz free energy change in the process of tensile deformation. Comparisons with Gaussian chains are made, and our results are close to those obtained from the Roe and Krigbaum theory.

关 键 词：聚亚甲基链 链段取向 弹性形变 旋转异构态模型 高聚物 

分 类 号：O631.21[理学—高分子化学]