均聚物结晶与熔融化转变的稳态和亚稳态统计理论Ⅴ 分子分凝统计结晶动力学—结晶增长速率对结晶生长机制和高聚物起始结构的依赖性  

Statistical Theory of Stable and Meta-stable Transition for Crystallization and Fusion of Homopolymers V Statistical Dynamics of Polymeric Crystallization by Molecular Segregation—Dependence of Growth-Rate for Crystals on the Grown Mechanism and Initial

作　　者：宋名实[1] 徐强[1] 胡桂贤[1] 王海侨[1] 吴丝竹李效玉 

机构地区：[1]北京化工大学可控化学反应科学与技术基础教育部重点实验室,北京100029

出　　处：《Chinese Journal of Chemical Physics》2005年第4期495-504,共10页化学物理学报（英文）

基　　金：ProjectsupportedbytheSpecialFundsforMojorStateResearchProjectsofChina(G1999064809)

摘　　要：首先对结晶增长速率同浓度、分子量和链柔性依赖性进行总结,然后基于微晶核和粒———高分子键组网络结构模型和高分子分子分凝统计结晶动力学,根据高分子链组是微晶粒同连接链段复合体的结构特征及它们间存在的四个相关性(并存性、简并性、顺反式构象共存性和物料守恒性)的事实,成功地把连接链段缩短增长动力方程同微晶粒体积增大增长动力方程有机结合在一起,从理论上创建出一种微晶粒数增长速率和微晶粒尺寸增长速率表达的一般化计算法,推导出结晶体系的微晶粒数增长速率和微晶粒尺寸增长速率同四种增长机制(近邻折叠,近邻伸直,近邻折叠同近邻伸直并联并存和近邻折叠同近邻伸直串联并存)、结晶温度和高分子起始结构(分子量)间定量表达式.当把分子量的指数同链的构象分数相连后,就又从理论上得到了分子量指数同温度和链柔性间的关系式,并讨论了它们同增长机制间的关系.最后以大量结晶动力学实验数据对上述所得到的关系式进行了验证,结果表明它们均能同实验结果很好符合.First a short review on the dependence of growth-rate for crystals on the grown mechanism and initial structure of polymers was presented. Based on the structural model of micro-nucleus- and crystal-constituent chains and the feature of statistical dynamics for polymeric crystallization by molecular segregation, a general method for characteristics of the number growth-rate for micro-crystal-constituent chains and the size growth-rate for crystals was proposed. According to the method, a set of quantitative expressions for the correlation of the number growthrate and the size growth-rate to the four types of growth was obtained （ folding, extending and combination of folding and extending）. Their dependences of the crystalline temperature and the initial structure of polymers were also derived, then the exponential parameters of H for molecular weight were combined with the fraction of conformation on segments, a new correlation of the exponential parameter to the temperature of crystallization and the flexibility of polymeric chain was theoretically obtained, and the dependence of H on the different types of growth was also studied. Finally the relationship between the growth-rate for crystals and the molecular weight of polymers of solution was verified by a great number of experimental data, and an excellent agreement between the theoretical prediction and experimental data was obtained.

关 键 词：结晶动力学 结晶生长机制 结晶增长速率 结晶高分子的起始结构 

分 类 号：O631.1[理学—高分子化学]