Barrier Properties and Structural Study of Nanocomposite of HDPE/Montmorillonite Modified with Polyvinylalcohol

María C Carrera,Eleonora Erdmann,Hugo A Destéfanis

doi:10.1155/2013/679567

Abstract

In this work was studied the permeation of CO2in films of high-density polyethylene (HDPE) and organoclay modified with polyvinylalcohol (MMTHDTMA/PVA) obtained from melt blending. Permeation study showed that the incorporation of the modified organoclay generates a significant effect on the barrier properties of HDPE. When a load of 2 wt% ofMMTHDTMA/PVAwas incorporated in the polymer matrix, the flow of CO2decreased 43.7% compared to pure polyethylene. The results of TEM showed that clay layers were dispersed in the polymeric matrix, obtaining an exfoliated-structure nanocomposite. The thermal stability of nanocomposite was significantly enhanced with respect to the pristine HDPE. DSC results showed that the crystallinity was maintained as the pure polymeric matrix. Consequently, the decrease of permeability was attributable only to the effect of tortuosity generated by the dispersion ofMMTHDTMA/PVA. Notably the mechanical properties remain equal to those of pure polyethylene, but with an increase in barrier properties to CO2. This procedure allows obtaining nanocomposites of HDPE with a good barrier property to CO2which would make it competitive in the use of packaging.

Highlights

The barrier properties of polymers can be significantly altered by inclusion of impermeable lamellar fillers such as montmorillonites, with sufficient aspect ratio to alter the diffusion path of gas-penetrant molecules
In this work was studied the permeation of CO2 in films of high-density polyethylene (HDPE) and organoclay modified with polyvinylalcohol (MMTHDTMA/polyvinyl alcohol (PVA)) obtained from melt blending
When a load of 2 wt% of MMTHDTMA/PVA was incorporated in the polymer matrix, the flow of CO2 decreased 43.7% compared to pure polyethylene

Summary

Introduction

The barrier properties of polymers can be significantly altered by inclusion of impermeable lamellar fillers such as montmorillonites, with sufficient aspect ratio to alter the diffusion path of gas-penetrant molecules. Enough articles in the literature have focused the studies on nanocomposites made by addition of organoclays, formed from montmorillonite, to thermoplastics using meltprocessing techniques [6, 7, 21,22,23,24,25,26]. This method involves the mixing of the layered silicate with the polymer and heating the mixture above its softening point. The heat stability was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)

Experimental

Results and Discussion

Conclusion