Short-Range Order in Polymer Liquids and Glasses

主要投资者先前的研究表明， 短程有序在确定 聚合物玻璃 为了证实这一点并获得进一步的信息， 关于聚合物液体和玻璃中的短程有序， 将采取以下三条方针。 一是 研究人员将对玻璃状样品进行X射线散射测量， 聚合物样品经受不同的机械和热 历史 他将使用中间人的技术- 角散射测量，他已经开发了较早，以及 能量色散X射线衍射技术。 二是他 将使用四种类型的中子散射测量 聚苯乙烯- -普通聚苯乙烯，全氘代聚苯乙烯， 仅在脂族基团上氘化的聚苯乙烯，和聚苯乙烯 仅在芳环上氘化。 结果可以提供 关于原子对类型的更多详细信息 负责短期订单的人 第三，分子 真实本体聚苯乙烯模型的动力学模拟， 进行，并将分析结果，以帮助 X射线和中子散射结果的解释。

The prior study by the principal investgator indicates the importance of short-range order in determining the properties of polymer glasses. To confirm this and obtain further information about the short-range order in polymer liquids and glasses, the following three lines of approach will be pursued. First, the investgator will perform X-ray scattering measurements on glassy polymer samples subject to different mechanical and thermal histories. He will empoly the technique of the intermediate- angle scattering measurement he had developed earlier, as well as the technique of energy-dispersive X-ray diffraction. Second, he will perform neutron-scattering measurement with four types of polystyrene - - ordinary polystyrene, perdeuteriated polystyrene, polystyrene deuteriated on aliphatic groups only, and polystyrene deuteriated on aromatic rings only. The results can provide more detailed information about the types of atomic pairs responsible for the short-rang order present. Third, molecular dynamics simulation of models of realistic bulk polystyrene will be performed and the result will be analyzed to aid the interpretation of the X-ray and neutron-scattering results.