Synthesis And Photopolymerization Of Two Novel Tetra-functional Methacrylate Monomers And Their Application As Dental Resin

Methacrylate resin-based dental restorative materials have attracted wide attentionbecause of their excellent adhesion and superior aesthetic qualities. Bis-GMA with bisphenolA structure is the most widely used dimethacrylate monomer in dental restorative materials asbase resin. However, resent researches have shown that bisphenol A derivatives havepotential damage to human body. Therefore, researches about applying novel methacrylatemonomer into dental restorative materials, which have no bisphenol A structure, are veryactive resent years. In this work, two novel tert-functional methacrylate monomers withoutbisphenol A structure were synthesized and their potential application in dental restorativematerials were also investigated. All the results of this study were listed as below.1. A novel tert-functional methacrylate monomer UtetraMA, which does not havebisphenol A structure, was synthesized using2-[(2-Hydroxy-ethyl)-methyl-amino]-ethnol,2-methyl-acrylic acid, IPDI, and glycidyl methacrylate as raw materials, and its structure wasconfirmed by FT-IR and1H-NMR spectra. UtetraMA was used as base resin to replaceBis-GMA in Bis-GMA/TEGDMA dental resin system totally or partial, the influence ofUtetraMA on properties of the copolymer was studied. The results showed that, with theincreasing of UtetraMA concentration in dental resin, double bond conversion andpolymerization shrinkage of resin system, water sorption and solubility, flexural strength andmodulus, and diameter tension strength of the copolymer increased significantly.2. Take UtetraMA/TEGDMA (50/50, wt/wt) as dental resin system, influence ofphotoinitiator CQ concentration on properties of the copolymer was investigated. The resultsshwed that, with the increasing of CQ concentration, double bond conversion andpolymerization shrinkage of resin system, hydrophilicity, flexural strength and modulus of thecopolymer increased. The mechanical strengths of all UtetraMA/TEGDMA copolymers meetthe requirement for dental polymer used in clinic.3. A novel tert-functional methacrylates monomer StetraMA with tertiary aminestructure was synthesized using neopentyl glycol diacrylate, diethanolamine, and2-methyl-acryloyl chloride as raw materials through Michael addition reaction, and itsstructure was confirmed by FT-IR and1H-NMR spectra. StetraMA was incorporated into Bis-GMA/TEGDMA as coinitiator, the influence of StetraMA on properties of the copolymerwas studies. The results showed that, with the increasing of StetraMA concentration,hydrophilicity and water sorption of the copolymer had no significant variation. Copolymerwith2.8wt%of StetraMA had the best comprehensive properties among all of copolymers.4. Take Bis-GMA/TEGDMA (50/50, wt/wt) as resin system,2.1wt%of StetraMA wasadded as coinitiator, influence of photoinitiator CQ concentration on properties of cured resinwas investigated. The results revealed that, with the increasing of CQ concentration, doublebond conversion, polymerization shrinkage, water sorption and solubility increased, watersolubility had no variation, and flexural strength and modulus were improved significantly.The mechanical strengths of all copolymers meet the requirement for dental polymer used inclinic.