Shape memory poly(carbonate urethanes) with high switching temperatures

Shape memory polymers (SMPs) have garnered significant attention as a versatile platform technology. However, their application in aerospace, automotive, and fire protection sectors is often limited by low switching temperatures and inadequate temperature stabilities. This study introduces three thermoplastic polyurethanes (TPUs) that exhibit temperature stabilities of up to 260 °C, as determined by thermogravimetric analysis. The poly(carbonate urethanes) demonstrate a consistent increase in glass transition temperature with higher hard segment content, as characterized by differential scanning calorimetry and dynamic mechanical analysis. After programming, switching temperatures were estimated to range from approximately 90 °C to 135 °C based on thermomechanical measurements. The production of thermoresponsive cuboid objects through 4D printing was successfully demonstrated in two material examples. With their unique thermal properties, the presented shape memory TPUs offer significant potential for broadening the application of SMPs in demanding technical fields.