Thermal management ability and flame retardancy of silicone rubber foam filled with flame retardant phase change capsules

A novel phase change capsule with layered double hydroxide (LDH) modified SiO2 shell (named M-EPCM) was designed and prepared, which was used to improve the thermal regulation performance and flame retardancy of silicone rubber foam (SRF). The SRF-3 composite containing 18 wt% M-EPCM presented greatly improved thermoregulation ability, and excellent thermal reliability even after 100 cycles. Besides, SRF-3 also exhibited excellent flame retardancy, with the limiting oxygen index exceeding 31.0%, reduced peak heat release rate (36.4%) and low total smoke yield (13.8 m2). The flame retardant mechanism analysis revealed that barrier effect, catalytic crosslinking and polyaromatic reaction provided by LDH played an important role. Moreover, SRF composites have outstanding mechanical properties, especially SRF-3 which showed a 150% and 85% increase in tensile strength and compression strength compared with pure SRF, respectively. This article provides a new idea for further application of LDH in the field of thermal management.