Preparation of lightweight polycarbonate composite foams with robust hollow glass microspheres via CO2 foaming

Polycarbonate (PC) composites are often used in the production of high value‐added products, but it is necessary to improve its environment stress cracking condition in the presence of pre‐strain and soluble solvents. In this work, the effect of weight reduction and strengthening is realized by introducing microstructures and hollow glass microspheres (HGMs) into the PC composites. It is found that the addition of HGMs can reduce the melt viscosity and Tg value of the composite materials, which will change the foaming behavior of PC/HGMs composites. Besides, the effect of different content of HGMS and foaming temperature on the foaming behavior of PC/HGMs composite foams are studied. The PC/HGMs composite foams exhibit a typical structure of both large and small cellular pores, because of the existence of hollow beads and cellular structures. Moreover, compared to the neat PC foam, the tensile strength as well as the flexural strength of the composite foams are significantly increased by 110.9% and 364.7%, respectively. Furthermore, the as‐prepared PC/HGMs composite foams have low thermal conductivity (lower than 0.07 W/mK), which can effectively insulate heat propagation. Highlights Hollow glass microsphere can reduce melt viscosity and Tg of composites. The mechanical properties of composite foams have been greatly improved. Composite foams exhibit excellent thermal stability due to their microstructure. The effect of weight reduction and strengthening is realized by introducing microstructures and hollow glass microspheres (HGMs) into the PC composites.