Organogelators and Their Application in Dental Materials
Elizabeth Wilder, Janet Quinn, Joseph M. Antonucci
Dibenzylidene sorbitol (DBS) is an organic molecule capable of inducing physical gelation in a wide variety of organic solvents and polymer melts by forming three-dimensional networks. Recent efforts in this laboratory have found that DBS is capable of gelling a wide variety of dental monomers including ethoxylated bisphenol-A dimethacrylate, triethylene glycol dimethacrylate and 2-hydroxyethyl methacrylate. This research was aimed at determining the effect of DBS on vinyl conversion, polymerization shrinkage, and mechanical strength of bioactive dental composites containing zirconyl-modified amorphous calcium phosphate (Zr-ACP) and a polymer matrix derived from the photopolymerization of ethoxylated bis-phenol-A dimethacrylate (EBPADMA).Fourier-transform infrared spectroscopy (FTIR) results indicate that DBS has a positive impact on vinyl conversion of EBPADMA but very little impact on the conversion of EBPADMA/Zr-ACP composites. However, dilatometry reveals that DBS significantly reduces the polymerization shrinkage of the EBPADMA/Zr-ACP composites. Addition of DBS was also observed to have a beneficial impact on the biaxial flexural strength (BFS) and modulus (E) of EBPADMA/Zr-ACP composites. Optical micrographs of the BFS-fractured surfaces of the EBPADMA/Zr-ACP composites reveal that the composites containing DBS have both fewer and smaller pores, a possible explanation for the improvement in both biaxial flexural strength and modulus. These results indicate that DBS and other similar organogelators may be useful additives for improving the properties of polymeric dental composites and related biomaterials.
American Chemical Society Division of Polymer Chemistry|228th | |ACS