Yang Jiao, McCoy Benjamin J, Madras Giridhar
Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
J Phys Chem B. 2005 Oct 6;109(39):18550-7. doi: 10.1021/jp052219b.
We adopt a cluster size distribution model to investigate the kinetics of nonisothermal polymer crystallization. The time dependencies of polymer concentration, number and size of crystals, and crystallinity (in Avrami plots) are presented for different cooling rates. The incubation period is also investigated at different cooling rates and initial temperatures. The relationship between cooling rates and incubation time is presented graphically and compared with experimental measurements. The initial temperature (relative to melting point) has a significant effect on nonisothermal crystallization. A comparison of moment and numerical solutions of the population balance equations shows the influence of Ostwald ripening. Agreement between modeling results and experimental measurements at different cooling rates supports the application of the distribution kinetics model for nonisothermal crystallization.
我们采用簇尺寸分布模型来研究非等温聚合物结晶动力学。给出了不同冷却速率下聚合物浓度、晶体数量和尺寸以及结晶度(在阿弗拉米图中)随时间的变化关系。还研究了不同冷却速率和初始温度下的诱导期。以图形方式给出了冷却速率与诱导时间之间的关系,并与实验测量结果进行了比较。初始温度(相对于熔点)对非等温结晶有显著影响。总体平衡方程的矩解和数值解的比较显示了奥斯特瓦尔德熟化的影响。不同冷却速率下建模结果与实验测量结果的一致性支持了分布动力学模型在非等温结晶中的应用。