Reactive compatilization of PCL/WP upon addition of PCL-MA. Smart option for recycling industry

Abstract

Intelligent use of raw materials has been encouraged in both academia and industry; biodegradable polymers have been used for bio-composites development seeking the generation of new environmentally safe compounds. Therefore, this work aimed to develop poly (ε-caprolactone) (PCL) biocomposites upon wood powder (WP) addition and compatibilized by maleic anhydride grafted poly (ε-caprolactone) (PCL-MA). Bio-composites were processed in a corrotational twin screw extruder afterwards extruded granules were injection molded. Specimens were characterized by mechanical properties (impact, tensile and Shore D hardness), thermal deflection temperature (HDT), Vicat softening temperature (VST), differential scanning calorimetry (DSC), thermogravimetry (TG), contact angle and scanning electron microscopy (SEM). Increases in elastic modulus, Shore D hardness, HDT and VST were observed related to neat PCL; whereas losses were verified in impact strength, tensile strength and thermal stability. PCL-MA addition to bio-composites increased interfacial adhesion between PCL and WP, as verified by SEM images. WP addition made crystallization faster by approximately 10 °C. Apparently, in the investigated range of PCL-MA content no significant changes were displayed in mechanical and thermomechanical properties, although contact angle indicated at 10% of PCL-MA higher wettability between PCL and WP was reached, which are important findings for recycling industry, since WP can be used to develop higher performance bio-composites, economically viable, contributing to new sustainable products generation.