【作者】 沈俊芳；

【导师】 申长雨； 陈静波；

【作者基本信息】 郑州大学 ， 材料加工工程， 2006， 硕士

【摘要】 结晶性聚合物从熔融态冷却结晶过程中，往往伴随着球晶的生成。球晶的密度和尺寸分布直接影响着制品的热力学、光学及机械性能。为了描述在静态结晶条件下球晶的生长过程，本文围绕结晶过程中球晶的形态学演变进行了研究，主要工作如下： 1．基于球晶在静态结晶过程中对称生长的假设，建立了结晶性聚合物在静态等温和非等温结晶过程中的成核诱导时间模型、成核密度模型、晶体长大模型、碰撞模型和相对结晶度预测模型。为后面的工作奠定理论基础。 2．在理论工作的基础上，借助Visual C++编程工具开发了球晶长大过程动态显示程序。显示程序的主要功能是实现球晶在静态等温和非等温条件下的生长过程可视化模拟，从成核到球晶长大乃至球晶碰撞过程都可以通过程序动态显示。 3．考察了成型条件对球晶生长过程的影响。等温结晶过程通过分析三种不同结晶温度下球晶的生长情况，比较了结晶温度对球晶生长过程的影响。非等温结晶过程以温度场为基础，分析了制品厚度、边界温度及熔体温度对球晶长大过程中形态演变的影响。更多还原

【Abstract】 The spherulites will be born in the crystallization process of crystalline polymer from melt. The spherulites’ density and dimension have a profound effect on the polymer performance of thermodynamics/optics and mechanical behavior. The objective of this thesis is to build a model for the spherulites growth process in quiescent crystallization and dynamic display the growth process. The following works have been finished:1. Based on the assumption of symmetry growth in quiescent crystallization, the crystal morphology model (the induction time model/nuclei model/growth model/impingement model/the relative crystallinity mode) is established for crystalline polymer in quiescent isothermal and nonisothermal crystallization process.2. Based on the theory study, compile the program to dynamic display the process of spherulites growth from nuclei stage to impinge stage with Visual C++. Then, the spherulite’s size change will be displayed in picture from small nuclei to a spherulite with big dimension in time.3. Analyze the effect of confectioning condition on the spherulite morphology in quiescent isothermal and no-isothermal crystallization. In isothermal crystallization, analyzed the process in three crystallization temperature .The result indicated the spherulites’ density decrease and size increase with the crystallization temperature increasing. In nonisothermal crystallization, calculated the temperature field at the beginning, and then, analyzed the growth process of spherulite in different thickness, boundary temperature and melt temperature. The result indicated that the part’s thickness, boundary and melt temperature have a notable effect on the crystallization process.更多还原