Photopolymerization of poly(melamine-co-formaldehyde) acrylate for dental restorative resins

This paper describes the investigation of photoinitiated polymerization of poly(melamine-co -formaldehyde) acrylate (PMFA) by camphorquinone (CQ) and amines (AMH) by visible light (λ>400 nm). It was shown that as the concentration of CQ and/or AMH increases, the rate of polymerization reaches a maximum and then decreases. The double bond conversion of PMFA was 20–35%, whereas monomer conversion was 90–96%, depending on the polymerization conditions. Addition of inorganic filler up to 70 wt% did not significantly influence the polymerization kinetics. The final hardness of the photocured samples (with 70 wt% filler) was about half that found in a commercial dental restorative composite. The shrinkage of a composite with 70 wt% filler was 2.12%. Dental formulations based on photocuring of PFMA can be considered for clinical applications, after biological and toxicological evaluation.