摘要
Cyclic siloxane is an attractive building block for incorporation of silicon-containing units as well as their distinguished properties to polymer materials. This work reports the synthesis and characterization of a tetra-functional vinylbenzene compound possessing cyclic siloxane cores (cD 4 -4VB). Synthesis of cD 4 -4VB is carried out using cD 4 -4SiH as the reactive precursor and multiple-step reactions, including hydrosilylation, deacetylation, and S N 2 substitution. cD 4 -4VB is an effective monomer for preparation of the corresponding cyclic silicon-based thermosetting resins (CR-cD 4 -4VB). CR-cD 4 -4VB shows attractive film formability and good thermo-mechanical properties, including a storage modulus of 2.0 GPa, a glass transition temperature of 282°C, a thermal stability above 400°C, a high char yield (at 800°C in nitrogen) of 55 wt%, and a dielectric constant of 3.12 at 10 GHz. This kind of resins have potential of application for halogen-free flame retardants and high-performance polymer films.