The oxygen transmission rate, average volume of free-volume cavities (Vf) and fractional free volume (Fv) of polyamide 6,10 (PA610)/poly(vinyl alcohol) (PVA) (i.e. PA610xPVA05 y, PA610xPVA08 y and PA610xPVA14 y) blend films reduced to minimum values when their PVA contents reached corresponding optimal values. Oxygen transmission rate, Vf and Fv values obtained for optimal PA610xPVAz y blown films were reduced considerably with decreasing PVA degrees of polymerization. The oxygen transmission rate of the optimal bio-based PA61080PVA05 20 blown film was only 2.4 cm3 (m2·day·atm)−1, which is about the same as that of the most often used high-barrier polymer, ethylene–vinyl alcohol copolymer. Experimental findings from dynamic mechanical analysis, differential scanning calorimetry, wide-angle X-ray diffraction and Fourier transform infrared spectroscopy of the PA610xPVAz y blends indicate that PA610 and PVA in the blends are miscible to some extent at the molecular level when the PVA contents are less than or equal to the corresponding optimal values. The considerably enhanced oxygen barrier properties of the PA610xPVAz y blend films with optimized compositions are attributed to the significantly reduced local free-volume characteristics.
All Science Journal Classification (ASJC) codes
- Polymers and Plastics
- Organic Chemistry
- Materials Chemistry