聚苯乙烯-b-聚丙烯酸/聚苯乙烯在水中的自组装及胶束尺寸的研究

利用动态光散射、透射电镜研究了嵌段共聚物聚苯乙烯 b 聚丙烯酸(PS b PAA)与均聚物聚苯乙烯(PS)在选择性溶剂水中的自组装行为.由于均聚物PS与PS嵌段具有相同的结构单元,均聚物PS参与胶束的形成,和嵌段共聚物的PS链段一同组成胶束的核;在适当的均聚物分子量和含量条件下,PS b PAA PS可以自组装形成单分散的纳米胶束;通过改变体系中均聚物PS的分子量和含量可在较大范围内调变胶束的尺寸.

THE SELF-ASSEMBLY OF POLYSTYRENE-b-POLY(ACRYLIC ACID)/POLYSTYRENE IN WATER

The effect of polystyrene (PS) homopolymer on the diameter of micelles self-ass emb led by polystyrene-b-poly(acrylic acid) (PS-b-PAA) in water was stud ied by dynamic laser light scattering and transmission electron microscopy .The results show that polystyrene can take part in the self-assembly of block copoly mer PS-b-PAA in water and forms part of the core of the resulting core-sh ell mic elles due to the affinity between the PS homopolymer and the PS block,because th eir structures are the same.The micelles are generally monodisperse when the co ntent of the PS homopolymer is in a given region,as well as its molecular weight .Besides,it is also found that the size of the micelles can be controlled conven ient ly by adjusting the content and the molecular weight of the PS homopolymer.The h ydrodynamic diameter of the micellels increases from 60 nm to 95 nm as the weight ratio of t h e PS homopolymer to the PS block is increased from 1/1 to 4/1,and increases from 60 nm to 120 nm as the molecular weight ratio of the PS homopolymer to the PS b lock increases from 1/2 to 4/1.