Oxygen barrier properties of organic montmorillonite modified polyamide 11/Poly (vinyl alcohol) films

Organic montmorillonite (OMMT) nano‐platelets were exfoliated and well dispersed in fully bio‐based polyamide 11/Poly(vinyl alcohol) (PA11/PVA) blends. Significantly lower oxygen permeation rates (OTR) were detected for the PA11 72.5 PVA 27.5 OMMT x films than those of PA11 and PA11 72.5 PVA 27.5 films. An extremely low OTR of 0.218 cm 3 /m 2 ·day·atm was found for PA11 72.5 PVA 27.5 OMMT 1 film modified with 1 PHR optimum concentration of well dispersed OMMT nano‐platelets. Similarly, the free volume characteristics evaluated for PA11 72.5 PVA 27.5 OMMT x film series reduced to a minimum as the OMMT concentration reached the optimum value. As revealed by dynamic mechanical and differential scanning calorimetric analyses of PA11 72.5 PVA 27.5 OMMT x film series, all dynamic glass transition temperature ( T g ), melting temperature ( T m ) and percentage crystallinity ( W c ) values of PA11 72.5 PVA 27.5 OMMT x films were noticeably higher than those of PA11 72.5 PVA 27.5 film without addition of OMMT. In fact, T g s, T m s and W c s evaluated for PA11 72.5 PVA 27.5 OMMT x films increased to a maximum, as their OMMT reached the optimum concentration. The considerably enhanced oxygen barrier resistance found for PA11 72.5 PVA 27.5 OMMT x films was ascribed to the considerably reduced free volume characteristics and much longer permeation path caused by impermeably OMMT nano‐platelets well dispersed in PA11 72.5 PVA 27.5 OMMT x films.