Crystollization and Morphology Central of Polymer Chains in a Nanoscale space

为了建立聚合物合金的形态控制方法，我们研究了各种晶态-非晶态两嵌段共聚物及其与均聚物共混物的形态重组过程(结晶过程和熔融过程)和最终形态。结果如下：(1)我们发现聚己内酯嵌段聚丁二烯(PCL-b-PB)/聚己内酯嵌段聚丁二烯(PCL-b-PB)的最终形态强烈地依赖于熔体中的相结构。(2)我们根据无定形嵌段的玻璃化转变温度Tg解释了聚己内酯嵌段聚苯乙烯(PCL-b-PS)的形态，其中组成嵌段的结晶性显著地依赖于Tg。(3)用同步辐射时间分辨小角X射线散射(SAXS)定性地研究了PCL-b-PB的熔融过程。与PCL-b-PB的结晶过程和结晶均聚物的熔融过程进行了比较，发现PCL-b-PB的熔融过程是非常独特的。(聚合物杂志，30,628(1998))(4)用SAXS研究了PCL-b-PS中形成的形态与共聚物组成的函数关系，发现结晶度和最终形态与共聚物组成密切相关。(聚合物杂志30,968(1998))(5)我们定量研究了不同条件下PCL-b-PB的熔融过程，试图找出结晶-非晶嵌段共聚物的熔融机理，发现两个因素对PCL-b-PB的熔融起重要作用，一是在T_c处的非平衡结晶，二是晶态与非晶态之间的构象竞争。

We have investigated the process of morphological reorganization (crystallization process and melting process) and final morphology for various crystalline-amorphous diblock copolymers and their blends with homopolymers in order to establish the method of morphological control in polymer alloys. The results are summarized as follows :(1) We have found that the final morphology of poly(epsilon -caprolactone)-block-polybutadiene (PCL-b-PB)/poly(epsilon -caprolactone) depends strongly on the phase structure in the melt.(Polymer Journal, 29, 642 (1997))(2) We explained the morphology of poly(epsilon -caprolactone)-block-polystyrene (PCL-b-PS) on the basis of the glass transition temperature Tg of the amorphous block, where the crystallizabiity of the constituent block depends significantly on Tg. (Polymer, 39, 1727 (1998))(3) We investigated qualitatively the melting process of PCL-b-PB by time-resolved small-angle X-ray scattering (SAXS) with synchrotron radiation. The results were compared with the crystallization process of PCL-b-PB and the melting process of crystalline homopolymers, It was found that the melting process of PCL-b-PB was extremely unique. (Polymer Journal, 30, 628 (1998))(4) The morphology formed in PCL- b-PS was investigated by SAXS as a function of the composition in the copolymer, It was found that the crystallinity and final morphology depends intimately on the copolymer composition. (Polymer Journal 30, 968 (1998))(5) We investigated quantitatively the melting process of PCL-b-PB under various conditions and tried to find the melting mechanism in crystalline-amorphous block copolymers, It was found that two factors, nonequilibrium crystallization at Tc and conformational competition between crystalline and amorphous blocks, were important for the melting of PCL-b-PB.(Macromolecules, in press (1999))