Reaction Injection Molding and Foaming of Smart Biodegradable Polyurethane Based on Chemorheological Investigation

Growing environmental concerns and increasingly stringent regulations have accelerated the development of biodegradable polymer systems. Polyurethanes (PUs), widely used in diverse industrial applications due to their robust mechanical performance, are increasingly being explored in biodegradable forms. Among PU processing techniques, reaction injection molding (RIM) and foaming are extensively employed; however, both processes are highly sensitive to the initial viscosity and curing behavior of the reactive mixture. Despite this practical dependence, the chemorheological characteristics of biodegradable PU systems have not been sufficiently connected to process stability and final performance. In this study, a biodegradable PU based on a biopolyol, i.e., polycaprolactonediol (PCL), was synthesized and processed into molded parts and foams via RIM and chemical foaming. Rheological measur…