具有极性大侧基乙烯基聚合物的分子尺寸和均方二极矩  

Dimension and dipole moment of vinyl polymers with dipolar large side groups

作　　者：马海珠[1] 蔡红红[1] 金璐师[1] 

机构地区：[1]浙江工商大学信息与电子工程学院,杭州310018

出　　处：《中国科学：化学》2012年第7期1014-1021,共8页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(20904047)资助

摘　　要：基于旋转异构态模型和生成矩阵代数方法,重新推导了大侧基聚合物均方回转半径和均方二极矩等基础量公式,应用于对聚乙烯咔唑(PVK)、聚对氯苯乙烯(PPCS)、聚乙烯砒啶(P2VP)和聚乙烯砒咯烷酮(PVP)链构象-构型依赖性质的研究.计算得到其无规链的均方二极矩特征比分别为0.55、0.57、0.48和0.37,均方回转半径特征比分别为2.07、1.74、1.11和1.52,全同链温度系数在?6.1×10?3～2.1×10?3K?1之间,范围比间同和无规链大.比较各特征比变化曲线规律,发现PPCS、PVP和P2VP的基础量分别受聚合物聚合度、规整程度和构象能的影响相对比较明显,而大侧基使PVK的均方二极矩和均方回转半径特征差异显著;对照改进的计算结果表明,在计算均方二极矩和回转半径时考虑极性侧基的方向和尺寸是十分重要的,在聚合物极性和柔性分析中不能忽略极性大侧基的影响.The formulas of basic quantities,mean-square radius of gyration and mean-square dipole moment,are re-deduced by the rotational-isomeric-state model and the generator matrix method with considering large side groups of polymers.From investigation for the configuration-conformation dependent properties of poly（N-vinylcarbazole）（PVK）,poly（p-chlorostryere）（PPCS）,poly（2-vinyl pyridine）（P2VP） and poly（vinyl pyrrolidone）（PVP）,the characteristic ratios of mean-square dipole moment are obtained 0.55,0.57,0.48 and 0.37,respectively,and the ratios of mean-square radius of gyration are 2.07,1.74,1.11 and 1.52,respectively.The temperature coefficients of the isotactic chains,in range of ？6.1×10？3～ 2.1×10？3 K？1,are more than that of the syndiotactic chains and atactic chains.From comparing the constrained relation of the ratios,it is found that effect of polymerization degree of chains,the chain tacticity and conformational energies on the basic quantities of PPCS,PVP and P2VP are obvious relatively.Moreover,the larger side groups of PVK chain result in the greater characteristic differences between the mean-square dipole moment and mean-square radius of gyration.From contrasting the results of improved calculation,it is concluded that the consideration of orientation and dimension of dipolar side groups in calculation of mean-square dipole moment and radius of gyration are very significant.Therefore,it suggests that the effect of large dipolar side groups on the polarity and flexibility of polymers cannot be neglected.

关 键 词：聚乙烯咔唑 聚对氯苯乙烯 聚乙烯砒啶 聚乙烯砒咯烷酮 均方二极矩 均方回转半径 

分 类 号：O631.3[理学—高分子化学]