Compatibilization as a Procedure for Recycling of Commingled Polyolefin Waste

An efficient reactive compatibilization system based on the combination of liquid polybutadienes (both without and with functional groups) and dialkyl peroxide has been developed for polyolefin blends. Practical applications of the reactive blending procedure for recycling of commingled polyolefin waste were proposed. Tensile impact strength was used as the main criterion of compatibilization efficiency. Liquid polybutadiene without functional groups is an effective compatibilizer for the blends composed of virgin polyolefin components, while the properties of blends prepared from a control damaged polyolefin or from real polyolefin waste are more affected by maleinized liquid polybutadiene. Incorporation of a basic inorganic admixture and a small amount of elemental sulfur can increase the compatibilization efficiency. Uncompatibilized and reactive compatibilized LDPE/HDPE/PP model blends and blends of real polyolefin waste were studied by capillary rheometry. The flow behavior of reactive-compatibilized systems is close to that of uncompatibilized ones; these systems can be processed using current procedures of plastic industry.