Abstract: | Using a noncovalent functionalization strategy, hyperbranched polyborate (HBb) acts as a solubilizer for carbon nanotubes (CNTs), and a stable HBb‐CNT dispersion in N‐methyl‐pyrrolidone was produced. The thermal properties of the resulting HBb‐CNT/polybenzoxazine (B‐BOZ) composites and their carbonized structures were investigated. Scanning electron microscopy demonstrated that the fracture surface of HBb‐CNT/B‐BOZ composites was rather rough and plenty of plastic deformation was exhibited. Thermogravimetric analysis indicates an improvement in the thermal stability of the composite with CNTs, especially that of 2.0 wt% CNT modified composite. The increase in the thermal stability is due to the good nanotube dispersion and the effective polymer‐CNT interaction. Graphite‐like boron carbonitride ceramic compounds were found after the composites were carbonized at 1,100°C for 2 h, and there was more B‐C, B‐N, and C‐N bonds in the carbonized HBb‐CNT/B‐BOZ composite than that of HBb/B‐BOZ composite. The result implied that CNTs can promote the ceramic process of HBb/B‐BOZ composite, and the strategy of introducing ceramic precursor into polymer composites may be useful to improve their ablation properties. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers |