Innovative Cold Processing of PVOH-Based Composites: A Gate-to-Gate Life Cycle Assessment of Environmental Benefits

Conventional thermoplastic polymer composites are produced using energy-intensive equipment. From an environmental perspective, reducing energy and material consumption, as well as selecting polymers and fillers that biodegrade without harmful consequences for the environment, is considered good practice. In this work, polyvinyl alcohol (PVOH), a biodegradable and water-soluble polymer, was compounded with 30 w%, 40 µm long cellulose fibres. Conventional melt blending production and innovative cold processing were compared from a tensile testing, thermogravimetric, and life cycle assessment (LCA) perspective through primary data collection. The granule production process significantly affects the mechanical performance of injected samples, with a 23.4% drop in tensile strength and an increase of 67.9% in elongation at break. The thermogravimetric analysis reported slight differences due to an additional thermal process involved in the melt blending of PVOH. From an LCA perspective, the innovative cold blending of PVOH-based composites drops all environmental indicators by 58–92%, maximizing the reduction of the “Water use” indicator. The most impactful production phase in the analysed production processes was drying, accounting for 46% and 85% of the conventional melt blending and innovative cold-blending processes, respectively.