聚苯乙烯微球表面的聚集态结构和苯基堆砌

用扫描隧道显微镜(STM)研究微乳液聚合法制备的聚苯乙烯微球.STM图像显示这种聚苯乙烯微球的表面具有不同的聚集态结构.在表面的某些区域,聚合物链没有相互缠结现象,而是有序地堆积在一起.在适当的情况下,同一条链上的苯基还会堆砌起来,形成一种平行移位的结构,其类似于苯双分子的最稳定结构.还用STM研究了用苯溶胀过的聚苯乙烯粒子,并观察到了类似螺旋结构的聚合物链以及扭曲的聚合物链.在聚苯乙烯微球中,聚合物链段和苯基的有序堆砌状态的存在,是因为苯乙烯单体已经在微乳液内的某些区域堆砌成有序的状态.

The Coagulation and Phenyl Stacks on the Surfaces of Polystyrene Microparticles

The scanning tunneling microscopy(STM) was used to investigate polystyrene microparticles. The STM images show that the polystyrene surfaces have different modes of coagulation. In some regions, the polymer chains are found to be orderly packed without entanglement. In some proper case, the phenyl groups in the same chain can stack up as a parallel displaced(PD) structure, similar to that predicted for benzene dimers. The polystyrene microparticles swelled with a mount of benzene was also investigated, the polymer chains with helical structures as well as the polymer chains with distortion can be observed. The existence of the orderly packed polymer chains and phenyl stacks may be due to the fact that styrene monomer stack in an orderly fashion in some parts within micromicellae.