Polybenzoxazine/organosilicon composites with low dielectric constant and dielectric loss

The evolution of electronic communication technology raises higher requirements for low dielectric constant(low-k) materials. For this, a benzoxazine functional organosilicon(HP-aptes) with dense Si-O-Si crosslinking networks and large sterically hindered tert-butyl groups was prepared by the sol–gel method. Then, a series of polybenzoxazine composites(PPHP) were prepared from intrinsically low dielectric constant bis-functional benzoxazine monomer(P-aptmds) and HP-aptes. The double crosslinking networks of polybenzoxazine and organosilicon further increased the crosslinking density and decreased the dipole density of composites, which endowed the composites with enhanced low-k properties. When the content of HP-aptes is 30%(mass), the crosslinking density was 2.05 × 10-3mol.cm-3,while that of PP-aptmds was 3.31 × 10-3mol.cm-3. In addition, the dielectric constant and dielectric loss of PPHP composite at 1 MHz could reach 2.61 and 0.0056, respectively.