Ceramifiable silicone rubber (SR) composites with excellent self-supporting properties and ceramifiable properties were prepared by incorporating silicate glass frits (SGFs) and sodium tripolyphosphate (STPP) into the SR. Ceramic residues were obtained by firing ceramifiable SR composites at 700, 850, and 1000 °C for 30 min. The bending angles of the composites were tested for evaluating the self-supporting property. To evaluate the ceramifiable properties of the ceramifiable SR composite, flexural strength, water absorption, and bulk density of its residues were tested. It was found that the addition of STPP improved the shape stability and the self-supporting property of the composites at high temperatures. The flexural strength of the ceramic residue of the composite with STPP firing above 850 °C is more than 5 MPa. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis showed that the relative content of the crystalline phase was enhanced by about 25% due to the addition of STPP. Furthermore, a possible mechanism for the formation of the crystalline phase was proposed. Scanning elector microscope (SEM) and energy dispersive spectrometry (EDS) analysis demonstrated that with the temperature increase, the inter-infiltration between these melts became easier, which implies that the bulk density of the ceramic residue was improved.

Simultaneously improving the thermal conductivity and flame resistance of epoxy composite is still a challenge. Herein, a novel epoxy composite with high thermal conductivity and greatly enhanced flame retardancy was developed through constructing integrated three-dimensional (3D) network based on boron nitride (BN), talc, ammonium polyphosphate (APP). The thermal conductivity of the composite with filler network reached 3.04 Wm− 1K− 1, which was 15.2 and 3.1 times of those of pure epoxy and sample with random filler distribution. The LOI value of the composite with filler network reached 37.8%, which was 1.9 and 1.4 times of those of pure epoxy and sample with random filler distribution, respectively. In addition, the effects of various combinations of filler on the flame resistance of the epoxy composite was also evaluated. The prepared composite with filler network exhibited excellent shape stability and mechanical strength even after ablation at 1000°C. The network structure constructed by BN had a positive effect on heat transfer, while APP led to the formation of phosphoric acid at high temperature, adhering to talc and other residues together. A ceramic-like residue was formed on the firing surface, which enhanced the barrier effect of char layer and flame resistance of the composite.