Manufacture of biaxially-oriented polyamide 6 (BOPA6) films with high transparencies, mechanical performances, thermal resistance, and gas blocking capabilities

•Lab-made PA 6 with distinct RV have been prepared from CPL.•Physical characteristics of lab-made PA 6 depend on its RV.•After extrusion-molded and biaxially stretched, lab-made BOPA6 film have been prepared.•Lab-made BOPA6 film exhibits superior physical performances to commercial BOPA6 film.•It is a promising film for electrical encapsulation and food packages. Polyamide 6 (PA 6) with different relative viscosities (RV) have been prepared and their thermal, rheological as well as crystallization properties are highly dependent on their RV. Since PA 6 with RV of 3.16 exhibits the highest crystallization speed, it has been subsequently extrusion-molded to give lab-made PA 6 film. After biaxially stretched, lab-made biaxially-oriented PA 6 (BOPA6) films have eventually manufactured. Experimental results represent that lab-made BOPA6 film with biaxially stretching ratio of 300% performs superior physical properties to lab-made PA 6 film and commercial Unitika ON-15, proving that it is a highly potential polymeric film for electrical encapsulation and food packages.