Effects of acetophenone‐formaldehyde resin on the degradation of high‐density polyethylene by UV‐irradiation

Abstract

PurposeProposes to examine acceleration of photo‐oxidative degradation of high‐density polyethylene (HDPE) by using photosensitive acetophenone‐formaldehyde resin (AFR).Design/methodology/approachDegradation of HDPE by UV light was investigated in the presence of photosensitive AFR on natural weathering. The experiments were done at constant temperatures (40, 65 and 90°C). The results were determined by FT‐IR spectrophotometric and viscometric methods. Measurement of the rate of formation of carbonyl groups on the FT‐IR showed the evidence of degradation. The carbonyl indices of photo‐oxidation of HDPE with/without AFR were determined by FT‐IR spectroscopy. The molecular weights of the samples (Mη values) were measured by viscometry.FindingsThe amount of carbonyl present in the AFR containing HDPE samples and the changes in their molecular weights were found to depend on the irradiation period, temperature and amount of AFR in the mixture. The improvements in UV performance have been observed by using 1 per cent photosensitive AFR in the mixture. Photo‐oxidative degradation also appeared to be accelerated by heat.Research limitations/implicationsThis study can be focused on using photosensitive resins for the polymer degradations just as powder mixture, but the HDPE sample used did not contain antioxidants. From this point of view, commercial HDPE and AFR must be mixed as a film‐former and the AFR concentration will be higher than those of this work.Practical implicationsThis work provides technical information for the application of photosensitive resins for easy degradation of HDPE packaging materials.Originality/valueThe method in which a photosensitive resin is used in the polymer degradation may be a reference for other relevant studies.