结晶性聚合物在熔融态冷却过程中,往往伴随着球晶的生成,球晶的密度和尺寸分布直接影响到制品的热力学、光学及力学性能。文中研究了聚合物冷却过程中球晶的形态学演变;模拟了球晶在生长过程中的形态演化过程;考察了成核诱导时间、成核密度、生长速率和碰撞对球晶形态变化的影响;比较了等温和非等温条件下聚合物的结晶过程。研究结果表明,在等温结晶过程中随着温度的降低,晶粒越来越细化,结晶程度越来越大,球晶碰撞边界为直线;非等温结晶过程中由于温度一直在降低,不断出现新的球晶,晶体大小不一,碰撞后边界为曲线。
The spherulites will be born in the crystallization process of crystalline polymer from melt. The density and dimension of spherulites have a profound effect on the polymer performance of thermodynamics, optics and mechanical behavior. In this paper , the development of spherulites morphology in quiescent crystallization process was researched and simulated. The simulations included the dfect of induction time, nuclei density, growth velocity and impingment boundary on spherulites＇ morphology. The crystallization process of polymer was analyzed in quiescent isothermal and non-isothermal crystallization. The results show that the rate o{ crystallinity increases with the decrease of the temperature, the crystalline grain is more fine, and the crystal boundary shows straight lines in the isothermal crystallization process. During non-isothermal crystallization the new spherulite is constantly emerging, the size of crystalline grain is different, and the crystal boundary shows curves.
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