【摘要】 运用Monte Carlo法,模拟D,L-丙交酯(DLLA)与L-丙交酯(LLA)共聚体系,在不同投料比情况下的立体化学构型,计算了两种立体异构体在共聚高分子链中所占的比例,与各种异构体序列的长度分布;计算了轮数R;分析了竞聚率r和投料比p对DLLA-LLA共聚物的立体化学结构的影响,发现r直接影响立体异构序列的交替程度;计算了共聚链上四单元组和六单元组的含量,引用文献提供的13C NMR谱图进行验证;研究了共聚组成、重均序列长度等模拟结果与某些物性实验数据之间的关系,发现共聚物的结晶速率和一定范围内的重均序列长度有关。更多还原

【Abstract】 Monte Carlo method was used to simulate the stereochemistry configuration of DLLA-LLA copolymers with different in-feed ratio. The proportion of two kinds of isomers in the copolymer chain, the length distribution of each isomer sequence and Run numbers were also calculated. By analyzing the influence of reactivity ratio (r) and in-feed ratio (p) on the stereochemistry configuration of DLLA-LLA copolymers, it was found that r had distinct influence on alternate extent of stereoisomer sequence. The content of Tetrads and Hexads in the copolymer chain was calculated and certified by the "C NMR spectrum of the literature. Still, the relations between the simulation results, such as copolymer composition, weight-average sequence length, and some experiment results of physical properties were studied on. It was found that the crystalline rate correlates to the weight-average sequence length in some extent.更多还原