Preparation And Characterization Of Light-curable Polyether Polyurethane Elastomer

Polyurethane(PU)elastomer is a material with excellent performance prepared by the reaction of isocyanate and long-chain polyol.Polyurethane acrylate can quickly cure to form a film under light.In the elastomer component with polyurethane as the main component,polyurethane acrylate is added to realize dual curing of the elastomer,that is,the light curing reaction and the chemical curing reaction proceed at the same time,thereby accelerating the curing speed of the elastomer and improving its comprehensive performance.In this paper,polyurethane acrylate(PUA),hyperbranched urethane acrylic(HPUA),and silicone modified urethane acrylic(Si-PUA)were synthesized and applied to polyurethane elastomers.The curing process and mechanical properties of the obtained polyurethane elastomers were carried out.A detailed discussion.(1)PUA was prepared first,and its synthesis conditions and photocuring process were investigated.The experimental results showed that the polyol and MDI were reacted at 80°C for3.5h,90 ? for 0.5h to prepare PU prepolymer,and then reacted with hydroxyethyl acrylate at80°C for 3h to obtain PUA.Add quantitative photoinitiator 1,and the curing can be completed when ultraviolet light is 155 s.(2)Discussed the curing process of polyurethane elastomer with PUA.Experiments show that when the blending amount of PUA is 15%wt,the light conditions are visible light for 2min,ultraviolet light for 2min,and quantitative photoinitiator 1(the amount in PUA is 4.1%wt of component A and 1.4% of component B wt),when the distribution ratio of group A and group B is 1.4:5,the obtained polyurethane elastomer is completely cured for 9 days,the tensile strength is 1.620 MPa,the elongation at break is 1729%,and the hardness is 36.6 HA.(3)The synthesis of Si-PUA and its influence on the curing process of polyurethane elastomers are discussed.Experiments show that the blending amount of Si-PUA is 20%wt,visible light is 2min,ultraviolet light is 2min,quantitative photoinitiator 1(the amount in PUA is 4.1%wt of component A and 1.3%wt of component B)When the distribution ratio of A and B is 1.4:5,and the amount of drier is 3% of A,the curing time of the obtained polyurethane elastomer is shortened to 5 days,the tensile strength is 1.693 MPa,and the elongation at break is1012%.The hardness is 40.8 HA.(4)Finally,the impact of HPUA on the curing process of polyurethane elastomers is discussed.The experimental results show that the mixing amount of HPUA is 20%wt,visible light is 2min,ultraviolet light is 2min,quantitative photoinitiator 1(the amount in PUA is4.1%wt of component A and 1.3%wt of component B),When the distribution ratio of A and B is 1.2:5 and the amount of drier is 4% of A,the curing time of the obtained polyurethane elastomer is 5 days,the tensile strength is 1.005 MPa,the elongation at break is 1589%,and the hardness is 36.5 HA.