Combined Impact of Ultraviolet and Chemical Fluids on High‐density Polyethylene Packaging Material

Abstract

To investigate the ageing behaviour of filled plastic containers outdoors, square cuts of the wall of two high‐density polyethylene (HDPE) types were exposed to ultraviolet (UV) radiation at their front side and to specific liquid chemicals (de‐ionized water, surfactant or White Spirit) at their back. The UV radiant exposure at the front side was 80 MJ/m². To compare the actions of the different exposures, separate dark backside fluid exposures were performed, in parallel. Besides, UV weathering was carried out until a UV radiant exposure of 325 MJ/m², being roughly comparable to outdoor exposure of one year in Northern Australia. An unpigmented HDPE included in the investigation gave no sufficient protection for the White Spirit. In addition, it showed clear degradation after several of these exposures. In combination with the White Spirit, an increase of carbonyl bonds was measured, presumably assignable to degradation products of the White Spirit. For a pigmented HDPE material, with the implemented combined exposures, no relevant damage was observed, within applied the exposure period. Copyright © 2011 John Wiley & Sons, Ltd.

Dynamic Distribution of αc-Relaxation in Polyethylene Single Crystals Investigated by Single-Molecule Force Spectroscopy

“…Here, to quantify the dynamic distribution of α c -relaxation, we selected PE as the model system, which is the most widely used polymer material in packaging , high-voltage cables, lithium battery separators, and other fields due to its chemical stability, insulation, and outstanding mechanical properties. The single crystal grown from dilute solution has the most orderly chain arrangement, which is an ideal model for studying the relaxation phenomenon in the crystal region. − The force-induced melting pathway was studied on PE single crystals by AFM-based SMFS experiments.…”

Combined impact of UV radiation and nitric acid on high‐density polyethylene containers as a laboratory test

“…However, it was shown 2 for several transparent HDPE jerrycans that a simple storage of the 55% nitric acid (HNO 3 ‐55%) does not necessarily lead to oxidation. Instead, it was found that the UV radiation transmitted through the HDPE can decompose the filling good 3 and then the resulting decomposition products damage the HDPE (secondary damage).…”