聚氧乙烯链构象性质的三级相互作用近似  

CONFIGURATION\|DEPENDENT PROPERTIES OF POLY(OXYETHYLENE) IN THE THIRD-ORDER INTERACTION APPROXIMATION

作　　者：陈英才[1] 罗孟波[2] 许健民[2] 宋栩冰[3] 

机构地区：[1]台州师范专科学校物理系,临海317000 [2]浙江大学物理系,杭州310027 [3]浙江大学化学系

出　　处：《高分子学报》2000年第6期672-675,共4页Acta Polymerica Sinica

摘　　要：基于旋转异构态近似模型 ,用半经验势函数计算了聚氧乙烯 (POE)链在三级相互作用下构象能 ,并用三级相互作用近似下的统计权重矩阵方法计算了POE链的特征比、偶极矩比等构象性质 .结果表明 ,当考虑了三级相互作用时 ,计算结果和实验值符合得比较好 ,与由二级相互作用近似得到的结果相比 。On the basis of rotational isomeric state (RIS) theory,the first\|order,second\|order,and third\|order conformational energies were calculated for poly(oxyethylene)\[(CH\-2—CH\-2—O)\-x\] (POE)chain using semiempirical potential function.Configuration\|dependent properties of POE chains,such as the characteristic ratio <r\+2>/nl\+2 ,the dipole moment ratio <μ\+2>/nm\+2 and their temperature coefficients dln <r\+2> /d T and dln <μ\+2>/ d T ,were calculated using the statistical weight matrix method,where <r\+2> is the meam\|square end\|to\|end distance, <μ\+2> is the meansquare dipole moment, n means the length of chain, l and m are the bond length and bond dipole moment,respectively.Results showed that,for long POE chains <r\+2>/nl\+2 =4 9,dln <r\+2>/ d T =-1 5×10 -3 K -1 , <μ\+2>/nm\+2 =0 49,and dln <μ\+2> d T =2 8×10 -3 K -1 .All these values are better than those obtained from the second\|order interaction approximation,and the characteristic ratio and the dipole moment ratio are in good agreement with early experimental findings.

关 键 词：聚氧乙烯链 三级相互作用近似 构象性质 RIS 

分 类 号：O633.11[理学—高分子化学] O631.12[理学—化学]