Characteristics of the sorption of water and an ethanol/water solution by light-cured copolymers of 2-hydroxyethyl methacrylate with dental dimethacrylates

摘要

This work concerns the synthesis of copolymers of 2-hydroxyethyl methacrylate (HEMA) and the dimethacrylates bisphenol A glycol dimethacrylate, bisphenol ethoxylated dimethacrylate, urethane dimethacrylate, and triethylene glycol dimethacrylate (50/50 mol/mol) because of their potential use in contemporary dentine adhesives. Copolymerization was carried out at room temperature with visible tight (lambda(max) = 470 nm), with the system camphorquinone/N,N-dimethylaminoethyl methacrylate being used as the photoinitiator. The behavior of these copolymers under oral conditions is of great concern. Thus, the sorption/desorption kinetics of water and a 75 vol% ethanol/water solution (which is an oral/food simulating liquid) by these copolymers were studied. The maximum amount of sorbed/desorbed liquid, solubility, and diffusion coefficient of each liquid were determined. The amount of sorbed liquid and solubility of the copolymers depended on both the structure of the copolymer and the nature of the solvent. The amount of water sorbed by the copolymers and their diffusion coefficients were much lower than those of the HEMA homopolymer but closer to those of the homopolymers of the dimethacrylate comonomers. All the copolymers sorbed a higher amount of the ethanol/water solution than water. (C) 2008 Wiley Periodicals, Inc.