New polymeric materials for use in glass-ionomer cements

The polymeric materials currently used in GIC are based on poly(acrylic acid), poly(acrylic acid-co-itaconic acid), or poly(acrylic acid-co-maleic acid). For the visible light cured (VLC) type GIC, the polymeric material is chemically modified to have pendant free-radical polymerizable double bonds, with the aqueous formulation solution also containing a monomer having methacrylate groups. Exploring ways to improve both conventional and VLC GIC, routes to new acrylic acid copolymers have been explored, where acid groups are made more available for salt-bridge formation. In particular, amino acid modified acrylic acid copolymers have been prepared and shown to provide improved GIC. Also, it was discovered that the monomer N-vinylpyrrolidone (NVP) could be used to modify acrylic acid copolymers to provide a path to improved GIC. A new route to develop VLC GIC, based on the reaction of the acid copolymer, in water, with a cyclic imino ether (oxazoline) functionalized methacrylate monomer was developed. Looking for ways to change the microstructure of the acrylic acid copolymers, as a possible route to improve GIC, acrylic acid copolymers have been prepared under super critical conditions. A review of the aforesaid areas of research is provided in this manuscript. (c) 2006 Elsevier Ltd. All rights reserved.