ABSTRACT The enthalpy transformation method, a widely accepted way to solve the phase transition related problems, was utilized to investigate the relationship between solidification behavior and crystallization kinetics of isotactic polypropylene (iPP). Our findings suggest that the cooling medium temperature is more effective in controlling the average cooling rate than the melt temperature. A generalized equation, which was obtained by plotting the cooling curves in a double-logarithmic scale, could be adopted to estimate the minimum cooling time (MCT) of the crystalline polymer to optimize the design of an injection molding (IM) cycle. Moreover, the quantitative description of the position dependence of the crystallization rate was also established. The present study will be of practical use to further exploration of the correlation between cooling parameters and the structural evolution of crystalline polymers as well as a better understanding of microstructural formation mechanisms.

中文翻译：

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等规聚丙烯 (iPP) 结晶动力学和凝固行为的焓转化研究

摘要 焓变法是一种广泛接受的解决相变相关问题的方法，用于研究等规聚丙烯 (iPP) 的凝固行为与结晶动力学之间的关系。我们的研究结果表明，冷却介质温度在控制平均冷却速率方面比熔体温度更有效。通过以双对数标度绘制冷却曲线而获得的广义方程可用于估计结晶聚合物的最小冷却时间 (MCT)，以优化注塑 (IM) 循环的设计。此外，还建立了结晶速率的位置依赖性的定量描述。