Onium salt reduces the inhibitory polymerization effect from an organic solvent in a model dental adhesive resin.
This study evaluated the effect of organic solvent concentration on the polymerization kinetics for a model dental adhesive resin containing a ternary photoinitiator system. A monomer blend based on the bis-GMA, TEGDMA, and HEMA was used as a model dental adhesive resin, which was polymerized using a binary system [camphorquinone (CQ) and ethyl 4-dimethylamine benzoate (EDAB)] and a ternary system [CQ, EDAB, and diphenyliodonium hexafluorphosphate (DPIHFP)]. Additionally, these blends had 0, 10, 20, 30, and 40 wt % ethanol added. Real-time Fourier transform infrared spectroscopy was used to investigate the polymerization reaction over photoactivation time. Data were plotted, and Hill's three-parameter nonlinear regression was performed for curve fitting. The addition of a solvent to the monomer blends decreased the polymerization kinetics, directly affecting the rate of polymerization, delaying vitrification, and attenuating the Trommsdorf effect. The introduction of DPIHFP displayed a strong increase in reaction kinetics, reducing the solvent inhibition effect. After 10 s of photoactivation, the binary system obtained in 0, 10, 20, 30, and 40% of ethanol, a degree of conversion of 44.6, 26.3, 13.4, 1.15, and 0.0%, respectively, whereas when a ternary system was used, the values were 54.6, 40.5, 27.4, 14.5, and 3.4%. An improvement was observed in the polymerization kinetics of a model dental adhesive resin when using a ternary photoinitiation system, making the material less sensitive to the residual presence of a solvent before photoactivation.
D000180:Acrylic Resins / Q000737:chemistry*; D000268:Adhesiveness; D019817:Benzoic Acid / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D004867:Equipment Design; D000431:Ethanol / Q000737:chemistry; D007259:Infrared Rays; D007700:Kinetics; D008027:Light; D008956:Models, Chemical; D009861:Onium Compounds / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013729:Terpenes / Q000737:chemistry
D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D009861:Onium Compounds; D009930:Organic Chemicals; D011108:Polymers; D011140:Polyurethanes; D012997:Solvents; D013729:Terpenes; D000431:Ethanol; C048339:camphoroquinone; D019817:Benzoic Acid