Evaluation of thermal and mechanical properties of the composite material of LignoBoost- lignin and recycled polyurethan : A preliminary feasibility study for a novel composite material from waste materials

Abstract: The purpose of this study was to investigate the possibility of producing a composite material of lignoBoost- lignin and recycled polyurethane. Also, the study evaluated the thermal and mechanical properties of the composite materials. These properties were investigated in a number of steps by applying different: additives, concentrations, conditions (temperature, time, and pressure), and equipment. The results from the preliminary trials show that it was impossible to produce a composite material from lignin/polyurethane blends. Hence, the blends were modified by adding acrylate and glycerol as a copolymer and plasticizer, respectively, to improve the compatibility of the blends. Fourier Transform Infrared Spectroscopy (FTIR), differential scanning calorimetry (DSC), and tensile tests were carried out to study the thermal and mechanical properties of (lignin/ polyurethane/ acrylate/ glycerol) composite materials. The FTIR results indicated the existence of intermolecular interactions between the components in the blends. The DSC analysis revealed the existence of two glass transition temperature (Tg) values, indicative of an immiscible blend. However, the first Tg and melting temperature (Tm) of composite material decreased with increased lignin content up to 40%. As a result of interactions, the maximum strength and Young’s modulus increased with increased lignin content up to 40 %. Meanwhile, elongation at break decreased with increased lignin content.