The main purpose of this work was the valorization of waste wood flour as reinforcement in order to develop new wood‐based polymer composites (WBPCs). For that purpose, low‐density polyethylene/poly(lactic acid) (LDPE/PLA) blends were prepared in presence of poly(ethylene‐co‐glycidyl methacrylate) (PE‐g‐GMA) as compatibilizer and reinforced with 0–40 wt% of wood flour. The tensile properties, Charpy impact strength, morphology, and thermal properties (differential scanning calorimetry (DSC) and thermogravimetric analysis [TGA, DTG]) of the LDPE/PLA/PE‐g‐GMA (20/80/5) composites were characterized. The results showed that Young's modulus increased with increasing the wood flour content and the composites are brittle. Globally, stress at break, elongation at break, and Charpy impact decreased with increasing the content of wood flour. Morphological investigation revealed a good interfacial adhesion between LDPE/PLA/PE‐g‐GMA blend and wood flour. The stability of composites was affected by the incorporation of 10 wt% of wood flour and varied slightly with the increase in load. The values of speed of maximal weight loss of the composites were lower than that obtained for the blend without wood flour. The dispersion of wood flour decreased the onset degradation temperature of PLA, while the rate of thermal degradation of composites was improved. On the other hand, the degree of crystallinity of composites increased by the addition of wood flour indicating the possibility that wood flour can act as nucleating agent. Finally, the water absorption of the composites depends on the immersion time, the nature, and the content of the load. J. VINYL ADDIT. TECHNOL., 26:443–451, 2020. © 2020 Society of Plastics Engineers

This work deals with the valorization of waste jute fibers coming from carpet industries in the development of biocomposites based on blends of low-density polyethylene and poly lactic acid. First, low-density polyethylene /poly lactic acid blends of variable composition (100/0, 80/20, 50/50, 20/80, 0/100) were prepared. Their tensile properties and morphology were characterized. Tensile strength of the blends was lower compared to the pure poly lactic acid and the elongation decreased significantly with increasing poly lactic acid which is due to poor adhesion as evidenced by SEM analysis. These results indicated the incompatibility between low-density polyethylene and poly lactic acid. Thus, the aim of the second step was to find a relevant compatibilizer. For that purpose, five functionalized polyolefins were tested: poly(ethylene-co-glycidyl methacrylate) (8% glycidyl methacrylate) (PE-g-GMA), poly(propylene-co-ethylene-grafted maleic anhydride) (1.4% maleic anhydride) (PP-g-MA), poly(ethylene-co-acrylic-ester-co-glycidyl methacrylate) (E-AE-GMA) (8% glycidyl methacrylate, 24% methyl acrylate), polypropylene-grafted maleic anhydride (PP-g-MA) (high percentage maleic anhydride), poly(ethylene-co-butylacrylate-co-maleic anhydride) (E-BA-MAH) (6% butyl acrylate, 3% maleic anhydride). PE-g-GMA exhibited the best results in terms of tensile properties and morphology. Low-density polyethylene/poly lactic acid /PE-g-GMA (20/80/5) reinforced with 0-40 wt% jute fibers were prepared and characterized (tensile properties, charpy impact strength, morphology and thermal properties) in the last step. The results showed an improvement of tensile properties and a satisfactory interfacial adhesion between jute fibers and polymer blends. Furthermore, thermal stability was affected by the incorporation of 10% of jute fiber but varied very little with the increase in load.