Synthesis of Novel Monomer with Excellent Visible-Light Polymerization Ability and its Application to Dental Field

为了提高光固化丙烯酸酯树脂在吸湿条件下的机械强度，合成了一种在一个分子中同时含有丙烯酰基和甲基丙烯酰基的新单体--甲基丙烯酸三乙二醇酯(TEGAMA)。比较了TEGAMA与三乙二醇二甲基丙烯酸酯(TEGDMA)和双丙烯酸酯(TEGDA)的光聚合能力和力学性能(压缩强度)。用可见光(波长400 nm)照射含有0.5wt%对苯二酚和N，N-二甲氨基苯甲酸乙酯作为光引发剂的光固化单体。光照30s时，侧链上残留的单体数量和未反应的双键数量均高于TEGDMA树脂。但自60s辐照后，TEGAMA树脂的这些值都小于TEGDMA树脂的值。在整个光照过程中，TEGAMA树脂侧链上残留的丙烯酰基的数量高于甲基丙烯酰基的数量。从上述结果可以推测TEGAMA的光聚合机理是甲基丙烯酰基之间发生了一定程度的反应，然后由于反应活性较高的侧链上残留的丙烯酸酯基团多于甲基丙烯酰基而进行了较高的交联反应。评估了干燥和吸湿条件下的吸水量和抗压强度。TEGAMA树脂的吸水率和干燥条件下的抗压强度与TEGDMA树脂相近。吸湿条件下，TEGAMA树脂的压缩强度下降幅度小于TEGDA树脂。因此，丙烯酸酯-甲基丙烯酸酯单体能够提高二甲基丙烯酸酯的光聚合能力，且光固化的丙烯酸酯-甲基丙烯酸酯树脂的力学性能优于光固化的丙烯酸酯树脂。

To improve mecchanical strength under the hygroscopic condition of light-cured acrylate resins, a new monomer having both acryloyl and methacryloyl groups in one molecule, Triethyl-Ene-Glycol Acrylate-Meth-Acrylate (TEGAMA) was synthesized. Photopolymerization ability and mechanical properity (compressive strength) of TEGAMA were compared with dimethacrylate (TEGDMA) and diacrylate (TEGDA) of triethylenglycol. Photocurable monomers containing 0.5 wt% of comphorquinone and ethyl N, N-dimethylaminobenzoate as photoinitiators were irradiated with visible light (lambda>400 nm). When photo irradiation was carried out for the 30 seconds, both the amount of residual monomers and unreacted double bonds in the side chain were higher than these of TEGDMA resin. But ever since the 60 seconds irradiation, these values of TEGAMA resins were smaller than these of TEGDMA resins. The amount of residual acryloyl groups in the side chain of TEGAMA resins higher than that of methacryloyl groups throughout photoirradiation. From above mentioned results, photopolymerization mechanism of TEGAMA could be presumed that methacryloyl groups reacted with each others in some extent and after that, futhermore high cross-linking reaction was proceeded due to the residual acrylate groups in the side chain with higher reactivity more than methacryloyl groups. Amount of water adsorbed and compressive strength under dry and hygroscopic conditions were evaluated. The amount of water absorbed and compressive strength under dry condition of TEGAMA resin indicated almost same value of TEGDMA resin. The degree of the decrease of compressive strength under hygroscopic condition of TEGAMA resin was smaller than that of TEGDA resin. Therefore, it is concluded that the acrylate-methacrylate monomer is able to improve the photopolymerization ability of dimethacrylate and mechanical properities of the photocured acrylate-methacrylate resin is superior to the light-cured acrylate resin.