Mesomorphic Structures of Blended Biodegradable Polymers and their Morphologies

可生物降解聚合物包括合成的脂肪族聚酯和天然纤维素。近年来，这些聚合物在防止环境污染方面受到了很大的关注。特别是脂肪族聚酯的可得性得到了各行业的认可。本研究的目的是研究几种生物可降解聚合物，聚l -丙交酯（PLLA）、聚ε-己内酯（PCL）、聚琥珀酸乙酯（乙烯）及其共混物的精细结构。结果表明：(1)在等温结晶过程中，将聚四氟乙烯薄膜夹在两层聚四氟乙烯薄膜之间，建立了形成跨晶薄膜的特殊方法。在聚合物的TC结构中，层状生长主要发生在膜中心方向。(2) TC薄膜可达到最大拉伸比xi0。这种良好的可拉伸性与那些由三维多瓣球晶组成的薄膜有些不同。在绘制的TC膜表面观察到一种羊肉串结构。(3)在剪切作用下，采用稀溶液结晶技术获得了分离的羊肉串结构。通过透射电镜分析证实了与羊肉串结构相关的形态学特征。然而，我们无法从这些溶液培养的沉淀中获得ED模式。(4)我们还尝试通过改变PLLA/PCL共混物的混合比来形成TC结构。从共混聚合物中获得TC薄膜是非常困难的。预计一些表面因素会影响混合膜中核的形成。(5)利用DSC装置对混合膜的结晶动力学进行了研究。这条路线的工作将在未来继续进行，并形成TC结构。(6)本研究可获得溶液生长的聚琥珀酸乙烯晶体。我们检查了它们的形态和ED模式来确定晶格常数。少

Biodegradable polymers includes the group of synthesized aliphatic polyesters and natural cellulose. In recent years these polymers are very much interested in preventing from environmental pollutions. Especially the aliphatic polyesters are recognized in their availability by various industries. The purpose of this research is to investigate the fine structures of several kinds of biodegradable polymers, poly(L-lactide) (PLLA), poly(ε-caprolactone)(PCL), poly(ethylene succinate) and also their polymer blends.The results obtained are summarized as follows:(1) We established the special method in forming transcrystal (TC) films of PLLA, which had been sandwiched between two Teflon sheets during isothermal crystallization. In the TC structures of the polymers, the lamellar growth occurs mainly in the direction to the center of films.(2) The TC films could be dawn to the maximum draw ratio ofXI0. This good drawability is somewhat different from those films composed of 3-dimentionally deve … More loped spherulites. A kind of shish-kebab structures were observed on the drawn TC film surfaces.(3) The trial was made to obtain the isolated shish-kebab structure of the PLLA by 'dilute solution crystallization techniques under shearing forces. Morphological features related to the shishi-kebab structures were confirmed by transmission electron microscopy. However we could not obtain the ED patterns from those solution grown precipitants.(4) We also tried to form the TC structure of PLLA/PCL blends where their mixing ratio were changed in various values. It was very difficult to obtain the TC films from the blend polymers. Some surface factors were anticipated to influence the formation of nuclei in the blended films.(5)The crystallization kinetics studies were performed in the blended films using DSC apparatus. The works along this line will be continued in future as well as the TC structure formation.(6) Solution grown crystals of poly(ethylene succinate) could be obtained in this study. We examined their morphologies and ED patterns to determine the lattice constants. Less