平行板间高分子链构象熵的动力学Monte Carlo模拟  

DYNAMICAL MONTE CARLO SIMULATIONS ON THE ENTROPY OF POLYMER CHAINS CONFINED BETWEEN TWO PARALLEL PLATES

作　　者：陈英才[1] 王超[1] 罗孟波[2] 

机构地区：[1]台州学院物理系 [2]浙江大学物理系

出　　处：《高分子学报》2010年第9期1082-1087,共6页Acta Polymerica Sinica

基　　金：国家自然基金(基金号20874088)资助项目

摘　　要：用动力学Monte Carlo方法模拟了受限于两平行板之间的高分子链,并用扫描法计算了链的构象熵S,研究了构象熵相对于自由链的减小量(S0-S)与平行板间距D和高分子链长n的关系.结果证实了de Gennes的自由能标度关系,并给出了标度关系适用的范围.当D非常小时,高分子链受到强烈限制,S0-S与n成正比,表明单链节受到平行板的平均排斥作用力与链长无关.随着D增大,平行板对构象熵的影响越来越弱,单链节受到平行板的平均排斥作用力随链长的增长而增大.当D比较大时,平行板对构象熵的影响近似可以忽略,高分子链构象熵与自由空间中的结果一致.Dynamic Monte Carlo simulations are performed for polymer chains confined between two parallel plates.The configurational entropy S of the polymer chain is calculated by using the scanning method,and the influence of the distance D between the two parallel plates and chain length n on the entropy is studied.The dependence of entropy reduction（S0-S） on D verifies the scaling results of de Gennes.Moreover,our results give the regime of the scaling results.When D is very small,the polymer chains are confined markedly,and S0-S is proportional to the polymer chain length.The latter indicates that the average repulsive force of the two plates exerting on one segment tends to be independent of the chain length.With the increase of D,the influence of the two parallel plates on the entropy becomes weaker and weaker,and the average repulsive force exerting on one segment increases with the chain length.At large D,the influence of the plates on the entropy can be ignored,and the configurational entropy becomes the same as that in the free space.

关 键 词：受限高分子链 Monte CARLO模拟 扫描法 构象熵 

分 类 号：O631.3[理学—高分子化学]