Effect of ferric salt of orange peel solid fraction on photo-oxidation and biodegradability of LDPE films

Abstract

The present study is concerned with accelerating photo-oxidation and biodegradability of low-density polyethylene (LDPE) film in the presence of orange peel solid fraction (OPS), especially its ferric salt (OPSFe). Orange peel was made free from essential oils and pigments and then turned into a fine powder. The rate of photo-oxidative degradation of pure LDPE film and the blend samples, containing OPS/OPSFe at 0–5 wt% in combination with PE-g-MA as a compatibilizer at 1 wt% of LDPE, in exposure to artificial sunlight was monitored by determination of carbonyl index derived from FTIR spectroscopy and the variations in mechanical properties in terms of UV-irradiation time. The original and irradiated samples (300 h) were buried in agricultural soil simultaneously and their biodegradation was evaluated by weight loss measurement, optical microscopy, and also calculation of carbonyl index derived from FTIR spectroscopy. The results obtained revealed that OPSFe acts as a significant accelerator in photo-oxidation and subsequent biodegradation of LDPE in soil enviornment. It is concluded that by incorporating small amount of Fe3+ ions into the polymer blend, photo-oxidative degradation of LDPE film is much more developed. Increase in OPSFe loading contributes to enhance the rate of photo- and biodegradability of LDPE films.