Orientation of Crystals and Novel Functionality Produced by Control of Polymer-Solvent Molecular Compounds

点击翻译按钮获取中文摘要

The formation processes of gels and clathrate cocrystals have been studied by focusing on polymer-solvent molecular compounds formed in syndiotactic polystyrene (SPS), syndiotactic poly(p-tert-butylstyrene)(SPTBS), and isotactic polystyrene (IPS). The important results are as follows: (1) SPTBS was first proved to show sol conversion induced by light irradiation, suggesting that this novel phenomenon is a general reaction process in physical gels formed by way of the formation of polymer-solvent molecular compounds with side-chain chromophores of stereoregular polymers. It has been assured that this photo-induced sol conversion takes place only when polymer chains take fibrillar networks. The process can be explained by the excitation energy, which was absorbed by side-chain chromophore and was transferred non-radiatively to the solvent molecule in a molecular compound, swaying the molecular compound to dissociate. The sol conversion by light can be used as a new effective photo-responsive system. (2) Many physical gels of SPS, IPS and SPTBS with various solvents including fragrance have been examined in detail by determining temperature-concentration phase diagrams in order to study on morphology and stabilization. Consequently the morphology of polymer chains in these gels is clarified to depend on (i) rate of crystallization and (H) compatibility between solvent molecules and side-chain phenyl groups. (3) The conditions where guest molecules are highly oriented have been examined and monitored by our method of measuring angular distribution of polarized fluorescence by rotating sample films around the excitation light beam. Finally we have succeeded to show the preparation method of clathrate cocrystalline films where guest molecules have nearly the same arrangements all over the film, suggesting that we can prepare the novel films where functional molecules are highly oriented.