Facile preparation of super lightweight and highly elastic thermoplastic polyurethane bead blend foam with microporous segregated network structure for good interfacial adhesion

The foamability of three different grades of TPU beads was studied, and two of them were selected to fabricate super lightweight and highly elastic TPU blend foams. Four different types of TPU combination blend foams with a microporous segregated network structure (MSNS) were prepared by solution-compression molding in combination with supercritical fluid (SCF) foaming. The results showed that the interface was well combined, and a bimodal cell structure was produced; the continuous phase constituted a MSNS. All TPU blend foams exhibited good springback performance, among which, TPUb70/TPUc70 blend foam had lowest hysteresis loss (3.8%) and lowest stress loss (2.6%). Thermal conductivity results showed they all have good thermal insulation, and the lowest thermal conductivity was 0.037 W/(m·K) for TPUb70/TPUc70 foam. This study offers a simple and cost-effective approach preparing high-performance foams with cushion, sound and shock absorption, and heat preservation for use in electronics, home appliances, sports, etc.