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Microscopic Structure and Orientation in Solids and Gels of syndiotactic Polystyrene Revealed Using Luminescent Probe Method

用发光探针法揭示间同立构聚苯乙烯固体和凝胶的微观结构和取向

基本信息

批准号：
15550183
负责人：
ITAGAKI Hideyuki
金额：
$ 1.98万
依托单位：
Shizuoka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

1.Syndiotactic polystyrene (sPS) films including naphthalene (Np) as guest of its nanoporous δ crystalline phase have been prepared and characterized by fluorescence depolarization, X-ray diffraction, and infrared linear dichroism techniques. A nearly perpendicular orientation of the fused rings of Np guest molecules with respect to the chain axis of the δ crystalline structure has been established by an analysis of directions of transition moment vectors of infrared absorption peaks. Moreover, in some sPS films prepared under the aim to orientate the direction of each δ clathrate form crystals in sPS films, the intensities of the polarized fluorescence components of Np were found to change with the angles of the films set against the vibrational direction of polarized light. This method was found to be quite effective to clarify how guest molecules are oriented in films.2.Whether sPS forms gel or not is dependent on solvents. Our fluorescence probe technique clarified that in the case of solvents such as chloroform, benzene, and toluene there are some free volume for them to stay among sPS chains because of the formation of polymer-solvent molecular compounds. Conversely, in the case of solvents such as trans-decalin that are too large to stay among sPS chains, sPS cannot form polymer-solvent molecular compounds and consequently cannot form a perfect gel.3.We found the noble phenomenon that an excitation light beam of a fluorometer can make a sort of hole in gels of sPS. This photo-deformation of the gels has turned out to be related to the formation of a polymer-solvent compound. The vibrational motion of side-chain phenyl groups of sPS excited to the singlet excited state by light is concluded to sweep out solvent molecules having stayed among sPS chains, resulting that the irradiated part changes to a sol form.

1.制备了以萘(NP)为客体的间规聚苯乙烯(PS)纳米孔δ晶相，并用荧光消偏、X射线衍射和红外线性二色性技术对其进行了表征。通过对红外吸收峰跃迁矩矢量方向的分析，确定了NP客体分子稠环相对于δ晶体结构链轴的近乎垂直的取向。此外，在一些旨在定向δ包合物形成晶体方向的SPS薄膜中，发现NP的偏振荧光成分的强度随着薄膜与偏振光振动方向相反的角度而变化。这种方法被发现是非常有效地阐明客体分子在薄膜中的取向。2.SPS是否形成凝胶取决于溶剂。我们的荧光探针技术表明，在氯仿、苯和甲苯等溶剂中，由于形成了聚合物-溶剂分子化合物，它们有一定的自由体积停留在SPS链之间。反之，在反式十氢萘这样的溶剂太大而不能留在SPS链上的情况下，SPS不能形成聚合物-溶剂分子化合物，因此不能形成完美的凝胶。3.我们发现了荧光计的激发光束可以在SPS凝胶上打洞的崇高现象。凝胶的这种光变形被证明与聚合物-溶剂化合物的形成有关。SPS的侧链苯基受光激发到单重态的振动运动，扫除了停留在SPS链之间的溶剂分子，导致辐照部分转变为溶胶态。