Mussel-Inspired Approach to Constructing Dual Network Coated Layered Clay for Enhanced Barrier and Antibacterial Properties of Poly(vinyl alcohol) Nanocomposites.

Long Mao,Huiqing Wu,Jianda Xie,Yuejun Liu

doi:10.3390/polym12092093

Long Mao, Huiqing Wu + Show 2 more

Open Access

https://doi.org/10.3390/polym12092093

Copy DOI

Abstract

Inspired by complexation and mussel adhesion of catechol groups in tannic acid (TA), organophilic layered double hydroxides (LDHs@TA-Ti) were synthesized by forming a one-pot assembled TA-titanium (Ti) dual network coating on the surface of layered clay for the first time. LDHs@TA-Ti/poly(vinyl alcohol) (PVA) nanocomposites were prepared by the solution casting method. The results show that TA-Ti(IV) and TiO2 coordination compounds are simultaneously formed due to hydrolysis of titanium tetrachloride and complexation of TA in aqueous solution. Upon TA-Ti coatings onto the surface of LDHs, the antibacterial rate of LDHs@TA-Ti is up to 99.98%. Corresponding LDHs@TA-Ti/PVA nanocomposites also show outstanding antibacterial properties. Compared with pure PVA, LDHs@TA-Ti/PVA nanocomposites show a 40.9% increase in tensile strength, a 17.5% increase in elongation at break, a 35.9% decrease in oxygen permeability and a 26.0% decrease in water vapor permeability when adding 1 wt % LDHs@TA-Ti. UV transmittance (at 300 nm) of LDHs@TA-Ti/PVA nanocomposites decrease by 99.4% when the content of LDHs@TA-Ti reaches 3 wt %. These results indicate that PVA matrix incorporated with LDHs@TA-Ti could be used as a potential active packaging material to extend the shelf life of food products.

Highlights

Over the past few decades, increasingly serious environmental issues and food safety problems have led to the development and application of degradable active packaging materials [1]
The results showed that the thermal stability, mechanical and gas barrier properties of Layered double hydroxides (LDHs)@tannic acid (TA)-Fe(III)/Poly(ε-caprolactone) nanocomposite films were markedly improved with the addition of LDHs@TA-Fe(III)
Affected strongly by phenolic hydroxyl groups in TA, the infrared absorption peak of hydroxyl groups for LDHs@TA-Ti shifted to 3380 cm−1

Summary

Introduction

Over the past few decades, increasingly serious environmental issues and food safety problems have led to the development and application of degradable active packaging materials [1]. Among the widely recognized degradable polymers, poly(vinyl alcohol) (PVA) is a synthetic, versatile and water-soluble polymer used in the packaging industry due to its excellent film forming properties, oxygen barrier properties and chemical resistance [2]. In the face of various packaging conditions, deficient barrier and antibacterial properties of PVA have limited its wide application in active packaging materials [4]. In order to improve these deficiencies, one of the most effective methods is to prepare nanocomposites with enhanced properties by blending PVA matrix with functional nanoparticles in low volume, while its degradability. It should be noted that enhanced barrier and antibacterial properties together could significantly improve the function of active packaging materials (e.g., prolonging the shelf life of food and keeping the flavor of food)

Methods

Results

Conclusion