Preparation of biaxially oriented polyamide 6/polyketone/graphene oxide films with enhanced barrier and mechanical behaviors

Abstract

AbstractIn this study, biaxially oriented polyamide 6/polyketone/graphene oxide (PA6/PK/GO) films were prepared by melt blending then simultaneously biaxially stretched process, with the aim of obtaining high barrier properties films and improvements in their mechanical properties. The oxygen transmission rate of biaxially oriented PA6/PK/GO film significantly decreased with addition of polyketone and GO. It is surprising that the biaxially oriented process can excellently improve the barrier properties of biaxially oriented PA6/PK/GO film. For example, there was 94.7% OTR reduction of the film containing 20 wt% PK and 0.08 wt% GO compared with PA6 film at a stretching ratio of 3.3 × 3.3. It is due to more tortuous permeation path of oxygen molecule owing to molecular orientation during biaxially stretching, and higher relative crystallinity with addition of GO. The tensile strength of film was remarkablly improved by stretching orientation and increase GO concentration. However, the elongation at break of film was considerably reduced by increase of stretching ratio. Although addition of GO may slightly improve the elongation at break of film at low stretching ratio, there was dramatic decline of elongation at break with increasing the content of GO at a stretching ratio of 3.3 × 3.3.