Preparation of polyamide 6/polystyrene quasi-nanoblends by diffusion and subsequent polymerization of styrene in water-sorbed polyamide 6 pellets

摘要

Polyamide 6 (PA6)/polystyrene (PS) blends with an average particle size of 103 nm were prepared by diffusion and subsequent polymerization of styrene in water-sorbed PA6 pellets. The pretreatment of PA6 pellets in hot water is prerequisite for successful styrene diffusion. The diffusion process involves replacement of free water in the pellets by styrene, and should be carried out in neat styrene medium to provide concentration gradient between inside and outside of the pellets. The polymerization step was carried out in water medium with benzoic peroxide as the initiator. The diametrical distribution of PS in the blend pellets was investigated by Micro-FTIR, and molecular weight of PS was measured by GPC. DSC measurements showed that the diffusion and polymerization of styrene occur in the amorphous regions of PA6 where the pre-sorbed water locates. PA6/PS quasi-nanoblends reported in this work cannot be obtained by conventional methods. (C) 2016 Wiley Periodicals, Inc.