Biological recycling of plastics containing ester bonds

Abstract

Abstract Biodegradable blend plastics such as polycaprolactone (PCL)‐conventional plastics blends, PCL‐polystyrene blend foams, PCL‐poly‐3‐hydroxybutyrate (PHB) blends, PCL‐raw cornstarch (CS) blends and PCL‐CaCO 3 blends were developed. It was suggested that the thermophilic composting of biodegradable plastics containing PCL was one of powerful technologies for recycling of biodegradable plastics. Furthermore, we tried to get useful products from biodegradable plastics by microbial fermentation processes. Polypropylene (PP)‐CS blend and PCL‐CS blend plastics were aerobically converted into ethanol by Bacillus polymyxa. PHB and PP‐CS blend and PCL‐CS blend plastics were anaerobically converted into some organic acids and methane gas by mixed microbial cultures with a methanogenic bacterium.