Studies of silicon-containing maleimide polymers: 1. Synthesis and characteristics of model compounds

A series of the (N-maleimido phenoxy)silane monomers were synthesized by a two-step reaction for using as the application of flame retardant, functional modifier, or a photoresist material in deep-UV region. All of the monomers with maleimide ring were polymerized by radical polymerization in toluene solution using 2,2′-azobisisobutyronitrile (AIBN) as initiator so as to prepare homopolymers. The structures of the maleimide monomers were identified by 1H, 13C, 29Si NMR and element analysis. The chemical structures of polymers were identified by Fourier transform infrared reflection (FT-IR) spectroscopy. The molecular weight distributions of polymers were measured by gel permeation chromatography (GPC) equipment. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to analyze the thermal properties of the polymers. The degree of polymerization in silicon-containing maleimide polymers should be affected by side chains. The introduction of alkylsilane into a side chain of maleimide polymer may reduce the glass transition temperature (Tg) and thermal stability, but increase char yield of solid residue as an excellent flame retardant.