Thermomechanical pulp (TMP) fibres can serve as renewable, cost-efficient and lightweight reinforcement for thermoplastic polymers such as poly(lactic acid) (PLA). The reinforcing ability of TMP fibres can be reduced due to various factors, e.g., insufficient dispersion of the fibres in the matrix material, fibre shortening under processing and poor surface interaction between fibres and matrix. A two-level factorial design was created and PLA together with TMP fibres and an industrial and recyclable side stream were processed in a twin-screw microcompounder accordingly. From the obtained biocomposites, dogbone specimens were injection-moulded. These specimens were tensile tested, and the compounding parameters statistically evaluated. Additionally, the analysis included the melt flow index (MFI), a dynamic mechanical analysis (DMA), scanning electron microscopy (SEM) and three-dimensional X-ray micro tomography (X-μ CT). The assessment provided insight into the microstructure that could affect the mechanical performance of the biocomposites. The temperature turned out to be the major influence factor on tensile strength and elongation, while no significant difference was quantified for the tensile modulus. A temperature of 180 °C, screw speed of 50 rpm and compounding time of 1 min turned out to be the optimal settings.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.