Application of MMT modified by block copolymer in dental composite

Montmorillonite (MMT) of which the surface was modified with a block copolymer with crosslinkable units was incorporated into dental composites as nanofiller to improve dimensional and mechanical properties. A bifunctional block copolymer was prepared through controlled/‘‘living’’ radical polymerization technique. One block contained 2-isocyanatoethyl methacrylate and the other block contained poly(vinyl pyridine) units. The interaction of the 4VP units with the surface of MMT layers was examined by using X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FT-IR). The results showed that the polymerization shrinkages of the composites decreased as well as the compressive and flexural strengths of the composites were also improved.