Preparation and characterization of LDPE/PVA blend films filled with glycerin‐plasticized polyvinyl alcohol

ABSTRACT A series of LDPE/PVA blend films were prepared via a twin‐screw extruder, and their morphology, thermal property, oxygen and water vapor permeation, surface properties, and mechanical properties were investigated as a function of the PVA content. During the extrusion process of the blend films, glycerin improved the compatibility and processing conditions between LDPE and PVA. The melting temperature ( T m ), melting enthalpy (Δ H m ), crystallinity (%), and thermal stability of the thermal decomposition temperature ( T 5% ) of the LDPE/PVA blend films decreased with increasing PVA content. The oxygen permeabilities of the blend films decreased from 24.0 to 11.4 cm 3 ·cm (m 2 ·day·atm) − 1 at 23°C. The WVTR increased from 7.8 to 15.0 g(m 2 day) −1 and the water uptake increased from 0.13 to 9.31%, respectively. The mechanical properties of blend films were slightly enhanced up to 2% PVA and then decreased. The physical properties of the blend films strongly varied with the chemical structure and morphology depending on the PVA and glycerin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41985.