Enhanced oxygen-barrier and water-resistance properties of poly(vinyl alcohol) blended with poly(acrylic acid) for packaging applications

Abstract

To enhance the oxygen-barrier and water-resistance properties of poly(vinyl alcohol) (PVA) and expand its food packaging applicability, five crosslinked poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) blend films were prepared via esterification reactions between hydroxyl groups in PVA and carboxylic acid groups in PAA. The physical characteristics of the blends, including the thermal, barrier, mechanical and optical properties, were investigated as a function of PAA ratio. With increasing PAA content, the crosslinking density was significantly increased, resulting in changes in the chemical structure, morphology and crystallinity of the films. The oxygen transmission rate of pure PVA decreased from 5.91 to 1.59 cc m −1 day −1 with increasing PAA ratio. The water resistance, too, increased remarkably. All the blend films showed good optical transparency. The physical properties of the blend films were strongly correlated with the chemical structure and morphology changes, which varied with the PAA content.

Synergistic effect of α‐ZrP and graphene oxide nanofillers on the gas barrier properties of PVA films

“…The XRD results of PVA and PVA nanocomposite films are presented in Figure in order to understand the dispersion of GO, α‐ZrP and Z:G hybrids in the PVA matrix. For neat PVA, there is an intensive peak appearing near 2θ = 19.74° which can be assigned to the PVA crystalline phase . Additionally, after nanofillers were incorporated (1 wt % GO, 1 wt % α‐ZrP, and 1 wt % Z:G hybrids), there is only one peak the same as that of neat PVA with no characteristic peak of α‐ZrP and GO.…”

“…For neat PVA, there is an intensive peak appearing near 2u 5 19.748 which can be assigned to the PVA crystalline phase. 29 Additionally, after nanofillers were incorporated (1 wt % GO, 1 wt % a-ZrP, and 1 wt % Z:G hybrids), there is only one peak the same as that of neat PVA with no characteristic peak of a-ZrP and GO. This indicates that these nanofillers were fully exfoliated and dispersed homogeneously in the PVA matrix.…”

A Rechargeable Zn–Air Battery with High Energy Efficiency and Long Life Enabled by a Highly Water‐Retentive Gel Electrolyte with Reaction Modifier

“…[ 27 ] Another evidence of crosslinking is the appearance of a new pronounced bond assigned to CO stretching vibration at 1700 cm −1 for both PVAA and PVAA–GO, which is derived from the esterification reactions between carboxylic acid groups in PAA, GO and hydroxyl group in PVA. [ 28 ]…”

“…In the Raman spectra shown in Figure 2g, the band at 2923 cm −1 ascribed to the CH stretching mode and bands located in the 750–1500 cm −1 range can be distinguished for the PVA‐containing samples. [ 28b,29 ] The D and G bands related to the graphitic structures are pronounced for both GO and PVAA–GO, indicating the successful introduction of GO into the GPE. [ 30 ] To demonstrate the crucial function of PAA and GO in improving the water retention and ionic conductivity of the GPE, the water and alkali uptake behaviors of PVA, PVAA, and PVAA–GO were analyzed.…”

Effects of Heat Treatment and Tea Polyphenols on the Structure and Properties of Polyvinyl Alcohol Nanofiber Films for Food Packaging

“…Sagnelli et al [3] proved that blending polymers with other natural products is an effective method for improving the functionality of all-natural bio-plastics systems. Lim et al [5] developed water-resistant PVA films using crosslinked PVA/polyacrylic acid blends, and reported that the films showed lower oxygen permeability and greater water resistance than PVA alone. Yang et al [6] prepared PVA/chitosan nanofiber films via electrospinning, which were then crosslinked with glutaraldehyde vapor.…”