Preparation of continuous PBO fiber-filled silicone rubber with high thermal conductivity through simple Wrapping

With the development of the electronics, the demand for flexible thermal materials with high thermal conductivity continues to rise. Here, we report a type of thermally conductive silicone rubber (SR) prepared using continuous poly (p-phenylene benzobisoxazole) fiber (PBO). Through a process consistent with the layer stacking principle, continuous fibers are first immersed with SR or boron nitride (BN)/SR and then wound layer by layer onto a mold. Then, PBO/SR and PBO/BN/SR composites were prepared in the laboratory. In these composites, PBO fibers can directly form numerous thermal paths. Additionally, due to the traction and compression between fibers during the winding process, BN is distributed along the fibers. It allows BN to better form independent thermal paths and, together with PBO fibers, create a thermal network in SR. The thermal conductivity of PBO/SR and PBO/BN/SR composites can reach 5.656 W m−1 K−1 and 7.853 W m−1 K−1, respectively, with PBO and BN contents of 20 vol% and 10 vol%, respectively.