中文摘要：

以2种完全相容的多分散的聚合物树脂为研究对象,利用动态流变学手段实现了界面分子链扩散过程的实时检测.研究结果发现,完全相容的聚合物树脂之间的扩散动力学参数α具有相对分子质量差异的依赖性,两者之间相对分子质量差异越大,α值越大.通过流变学参数还可获得另一扩散动力学参数—特征时间tc,从而得以计算出组分之间扩散系数,研究结果表明所获得的扩散系数具有频率依赖性.

英文摘要：

A sandwich-like sample configuration of three polymer layers was designed and used for rheological probing of the chain interdiffusion of two miscible polydisperse polymers in the melt state. It was found that the interdiffusion process can be probed by the growth of the rheological responses with time as long as the polymer pair constituting the interface has an adequate difference in rheological properties and is miscible. To understand the rheological signal of the interdiffusion process, a phenomenal rheological model combined with a fitted model for the experimental data was proposed. With the two models, two important model parameters concerning the interdiffusion dynamics were discussed. The results show that the interdiffusion process can be probed by rheological properties and the dynamics of inter diffusion is greatly affected by the difference in the molecular weight between the polymer pair. The first parameter, the exponent a for the time dependent behavior of the interpenetration distance ,was found to be larger than the typical value of 1/2 ,which is ascribed to the dynamic dilution process as proposed in tube theories. While, by the other parameter,the characteristic time to, the interdiffusion coefficient can be estimated. It is noted that these two parameters were found to be frequency- dependent,which can be mainly ascribed to the polydispersity of the molecular weight. Finally, the results indicate that the fast-mode model is reasonable for the understanding of the interdiffusion process.