Enhanced Thermal Stability and Thermal Conductivity of Ti3AlC2/Silicone Rubber Composites

To address the trade-off among thermal conductivity, thermal stability, and flexibility of silicone rubber (SR) composites, a bioinspired dual-surface modification strategy was proposed to functionalize Ti3AlC2 MAX phase fillers with tannic acid (TA) and methyl triethoxysilane (MTES). TA was first self-assembled on the Ti3AlC2 surface to form an active adlayer, followed by MTES grafting to obtain Ti3AlC2@TA-MTES. The structure, morphology, and composition of the modified fillers were characterized by XRD, FTIR, XPS and SEM. The introduction of TA serves as a biomimetic intermediate platform rich in phenolic hydroxyl groups, providing abundant anchoring sites for subsequent MTES condensation. At 40 phr filler loading, the thermal conductivity of Ti3AlC2@TA-MTES/SR reached 0.76 W/(m·K), 55.1% higher than that of unmodified composites and 322% higher than that of pure SR. The composite with 30 phr modified filler exhibited excellent thermal stability (T10 = 512.1 °C, T50 = 613.4 °C) and enhanced mechanical properties. This work provides a feasible and scalable approach for fabricating flexible thermal management materials for high-integration electronic devices and flexible electronics.