Improvements in the oxygen barrier property of polypropylene nanocomposites

Abstract

A nanocomposite consisting of polypropylene (PP)/nanoclay (montmorillonite) was prepared by means of a melt-compounding process with the use of a twin-screw extruder. Because of the complex dispersion of polar and hydrophilic clays that have many cations in the nonpolar and hydrophobic PP, amino-silane was introduced to modify the surface of the clays. Also, to improve the compatibility of the modified nanoclay with PP, a PP-graft-maleic anhydride was used as a compatibilizer. From Fourier transform infrared spectroscopy analysis and the mechanical property test results, it was confirmed that the surface of the nanoclay was properly modified, and it was successfully dispersed in the PP matrix. The composite was investigated by electron microscopy to analyze its morphology and the degree of dispersion of the nanoclay. An analysis of oxygen permeability according to nanoclay content was performed, and it was found that the higher nanoclay content makes the decrease in oxygen permeability. In addition, a shelf-life test was carried out to determine the relationship between decreased oxygen permeability and food preservation performance. The preservation performance of the food package prepared with the resin made in this study was improved because of the improvement in mechanical properties and oxygen barrier property.

Polypropylene nanocomposites produced by in‐situ grafting of maleic anhydride using different mixing procedures

“…Moreover, the permeability of N2V and N5V is also lower than most results from the literature for PP/PPg NCs prepared with clays similar to the oMt used in this study and PPg/oMt ratios between 5:1 and 2:5. In the literature, values up to 20% and 40% lower than the corresponding PP are reported when 2 and 5 wt% clay are used, respectively 41,42,44–46 . One factor to take into account when analyzing the permeability of the NCs from Procedure V is that the PPg/oMt ratio surely decreases with clay concentration.…”

“…Gas permeability of NCs is a property that, for given ambient conditions, is mainly affected by crystallinity level of polymeric matrix, type and quantity of nano‐clay and compatibilizer, clay/polymer adhesion quality, and clay degree of disaggregation. With respect to clay and compatibilizer concentrations, in general it has been observed that oxygen permeability decreases as they augment 41,42,44–46 . Moreover, for a given filler content, the permeability reduction is higher as the degree of disaggregation of the clay and/or polarity and crystallinity of the matrix get larger.…”

In Situ Modification of Polyisoprene by Organo-Nanoclay during Emulsion Polymerization for Reinforcing Natural Rubber Thin Films

“…These peaks are assigned to the basal spacing of d 001 and d 002 , respectively. The basal spacing of d 001 is considered as an indicator of the interlayer distance between the silicate crystal plates of the nanoclay structure that can be calculated following the Bragg’s equation [46].…”

Polystyrene/Polyolefin Elastomer Blends Loaded with Halloysite Nanotubes: Morphological, Mechanical, and Gas Barrier Properties

“…[19] To deal with the nanofiller dispersion issue, a compatibilizer can be added to the polymer/HNT blend. [20,21] The impact of nanoparticles on the mechanical properties and gas permeability of polymer blends has been extensively studied in packaging applications. For example, Kubade et al [22] observed that by adding surface-modified HNTs to polypropylene (PP)/acrylonitrile butadiene styrene blends, significant improvements in the tensile strength (by ≈5 MPa) and tensile modulus (by ≈160 MPa) of the polymer blend sheet were achieved.…”

“…[ 19 ] To deal with the nanofiller dispersion issue, a compatibilizer can be added to the polymer/HNT blend. [ 20,21 ] The impact of nanoparticles on the mechanical properties and gas permeability of polymer blends has been extensively studied in packaging applications. For example, Kubade et al.…”