Development of Antimicrobial Packaging Film Made from Poly(Lactic Acid) Incorporating Titanium Dioxide and Silver Nanoparticles.

Wenhui Li,Lin Li,Tianqing Lan,Haiyan Chen,Hai Chi,Peng Han,Cheng Zhang,Yuyue Qin

doi:10.3390/molecules22071170

Abstract

Polylactide (PLA)/nano-TiO2 and PLA/nano-TiO2/nano-Ag blends films were prepared by a solvent volatilization method. Compared to pure PLA film, the nano-blend films have low water vapor permeability (WVP) and a poor transparency. With the increase of the NPs in the PLA, the tensile strength (TS) and elastic modulus (EM) decreased, while the elongation at break (ε) increased. SEM analysis indicated a rougher cross-section of the nano-blend films. According to the FTIR analysis, no new chemical bonds were formed in the nano-blend films. By using DSC to examine the crystallization and melting behavior, the result shows that the NPs have no effect on the glass transition (Tg) and melting temperature (Tm), but they caused an increase on the cold crystallization (Tc) and crystallinity (Xc). TGA results show that the addition of nanoparticles significantly improved the thermal stability. The PLA nano-blend films show a good antimicrobial activity against. E. coli and Listeria monocytogenes. Most important, we carried out migration tests, and verified that the release of NPs from the nano-blend films was within the standard limits.

Highlights

In last decades, a large number of plastic packaging bags have been produced from fossil fuels, and environmental pollution has become a global issue
The results suggested a high transparency of poly(lactic acid) (PLA) nano-blend films and the possibility to see through results suggested a high transparency of PLA nano-blend films and the possibility to see through the the packaging film, which is one ofofthe important requirements for consumers
We have investigated the effect of nano-TiO2 and nano-Ag particles on the water vapor permeability (WVP), mechanical properties, optical properties, microstructure, thermal properties and antimicrobial properties of PLA films

Summary

Introduction

A large number of plastic packaging bags have been produced from fossil fuels, and environmental pollution has become a global issue. One important way to solve the problem is to produce packaging bags using degradable materials [1]. Because the use of bio-based antimicrobial packaging materials can reduce the environment impacts, and offer protection for the produce against physical, chemical, and microbiological effects, bio-based materials have attracted extensive interest in the packaging field [2]. Poly(lactic acid) (PLA) which can be produced from the bacterial fermentation of normal renewable resources, like corn starch or sugar beet, and can be eventually decompose when it is buried is the ideal choice to achieve these goals [3]. Because PLA has been approved by the United States Food and Drug

Methods

Results

Conclusion