Study Of The Preparation And Mechanical Properties Of Hard UV-curing Polyurethane Acrylate Resin

Complying with the energy trend of the world and national environmental policy, UV-curing resin, what is known for its excellent performance, efficiency, low energy consumption and environmental, have been used in areas of coating, adhesive, priting ink. etc. In recent years, it is also developing rapidly in the medical dental materials and new manicure industry. Polyurethane acrylate(PUA), as one kind of UV-curing resin, could change its structure to math the different properties. PUA is one of the most hot topics.Now. the heat insensity of PUA has been rarely reseached. To the different based materials, the mechanical properties of PUA is hard to hold its high hardness and toughness at the sametime.To solve the problems, in this thesis, we prepared a series of UV-curing polyurethane acrylate prepolymer (PUA) with different structure. PUA were prepared through aliphatic isoporone diisocyanate(IPDI), different long-chain glycol(polyether polyol, polyester polyol) and hydroxyethyl methacrylate(HEMA). The UV-curing polyurethane acrylate resin were prepared by well mixing PUA, modified resin(MR) with high hardness, active diluents and photoinitiator. The UV-curing polyurethane acrylate resin cured to membrane through UV curing machine. Utilizing NDJ-8rotary viscometer and the low temperature water bath determined the bulk viscosity of PUA at25℃,60℃.The infrared spectra(FI-IR) exhibited the chemical structure of PUA and UV-curing polyurethane acrylate resin before and after curing. Utilizing DTA and UV spot light reseached the heat insensity of UV-curing polyurethane acrylate resin in the curing. Studying the cross-linking network structure of UV-cured resin was trough the swelling equilibrium experiment. The work mainly studied the effectors of the heat insensity and the mechanical properties. The main results and conclusions are as follows:(1) The heat intensity was obviously influenced by the content of photoinitiator and TMPTA. As the content of the photoinitiator increased, the maixmun peak of the heat intensity increased rapidlyl. When the content of1173was0.5%, the maximum heat intensity and the mechanical properties was the best.(2) With the content of MR increasing, the swelling rate of MPUA resin gradually decreased, reduced from53.35%to29.54%; the hardness of MPUA resin increased, improved from5B-6B to3B, but resistant90°bending performance changed from unfracture to fracture. The hardness of ZPUA resin increased gradually, but the toughness decreased. When ZPUA/MR=85/15, the hardness of the UV-curing polyester polyurethane acrylate resin reached to4H,.(3) Copolymerrization type polyether/polyester polyurethane acrylate resin superiored the blends of polyether/polyester polyurethane acrylate resin in the mechanical properties. The toughness of the former was obviously better than the latter in the same hardness condition.(4) With the rate of the polyester increased, the hardeness of the copolymerization type polyethe/polyester polyurethane acrylate resin increased gradually. When PUA/MR/1173was75/25/0.5, the ratio of polyethe/polyester was5:5,3:7,1:9, the mechanical properties of the correponding UV-curing resin met the expected target. The hardness was4H, resistant90°bending performance was not fractured.