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Diffusion and Morphology of Polymer

聚合物的扩散和形态

基本信息

批准号：
12127204
负责人：
MIYAJI Hideki
金额：
$ 6.98万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

In the last two years (2000 to 2001), we performed the experiment on crystal growth of polymers in thin films to obtain the following results. 1)The super-cooling (ΔT) dependence of the growth rate G of polymer crystals does not depend on the morphology and film thickness : G is proportional to exp(-K/TΔT).2) The lamellar thickness is determined by crystallization temperature ; the thickness is independent of morphology and film thickness. 3) In the crystal growth for a crystal with a finite width of the growth surface, is observed the ratio of the maximum growth rate to the minimum one to be inconsistent with that predicted by the standard nucleation theory.In 2002, we investigated thermal roughening in poly(1, 4 trans-butadiene) crystals arid kinetic roughening in poly(butene-1) crystals respectively, and established that result 1) holds universally in polymer crystallization. We confirmed result 3)for poly(vinylidene fluoride) crystals as well as for poly(para-phenylene sulfide) by observing the radial growth rate of their spherulites. On the basis of these observations, we have proposed a new model for polymer crystallization ; in the model a polymer segment experiences an activated free energy barrier due to an entropy loss before adhesion to the crystal surface.We also investigated the effect of diffusion on polymer crystallization by observing the crystallization of cross-linked polyisoprene rubber through stress-strain curve and X-ray measurement; thermodynamic analysis of these data could reproduce well the strain rate dependence of crystallization rate depending on crystallization temperature.

近两年（2000年至2001年），我们进行了薄膜中聚合物晶体生长的实验，得到了以下结果。 1) 聚合物晶体生长速率 G 的过冷 (ΔT) 依赖性不依赖于形态和膜厚度：G 与 exp(-K/TΔT) 成正比。2) 层状厚度由结晶温度决定；厚度与形态和膜厚度无关。 3) 在具有有限生长面宽度的晶体的晶体生长中，观察到最大生长速率与最小生长速率之比与标准成核理论预测的不一致。2002年，我们分别研究了聚(1, 4反式丁二烯)晶体的热粗糙化和聚(丁烯-1)晶体的动力学粗糙化，并确定结果1)在聚合物中普遍成立结晶。我们通过观察聚(偏二氟乙烯)晶体和聚(对苯硫醚)球晶的径向生长速率证实了结果3)。基于这些观察，我们提出了一种新的聚合物结晶模型；在模型中，聚合物链段在粘附到晶体表面之前由于熵损失而经历了激活的自由能势垒。我们还通过应力应变曲线和 X 射线测量观察交联聚异戊二烯橡胶的结晶，研究了扩散对聚合物结晶的影响；这些数据的热力学分析可以很好地再现依赖于结晶温度的结晶速率的应变速率依赖性。