| UV curing technology is being more widely used for its high efficiency of curing, fast curing, low curing cost, less pollution and so on.Epoxy acrylate is the most commonly used in UV-curable prepolymer,and its UV-cured product has excellent mechanical properties, adhesion and chemical resistance,it has been widely used in inks, adhesives and coatings, etc. However,it is applied in other areas is very limited because of its rigidity of epoxy acrylate is too large,and its products are lack of flexibility and brittleness. At present, research on the UV light is applied to the field of material damping rarely reported. In this paper, as well as by grafting suberate urethane acrylate blends and other ways to make two steps on toughening epoxy acrylate. Preparation of the damping performance and good overall performance UV-curable coating damping.Firstly, this article takes two-steps methord,and raw materials are Epoxy resin E-44, suberate and acrylic,and then make them into suberate modified epoxy acrylate. Studies have shown that the total reaction time was 6h. The first step for 4h at 90 ?conditions,and the second step for 2h at 100 ?conditions which can improve the reaction efficiency and reduced side reactions. Catalyst tetrabutylammonium bromide usage is 1% of the total mass of the system which should be added twice separately can get a better catalytic effect. Choosing mass fraction of 0.02% of the hydroxyl anisole as the damping agent can play a good effect of inhibiting polymerization.Besides, Selecting 50% by mass of toluene as a solvent can significantly improve the viscosity of the reaction system,and the side effects are reducing effectively. Using the suberate which mass fraction is 30% modified epoxy acrylate can reduce its tensile strength to 10.32 MPa. Elongation at break of it increased to 30%,and flexibility of the cured film is 2mm which is improved significantly.The improvement of flexibility is not obvious when the suberic addition amount is less than 30%. Prepolymer system viscosity increased rapidly and the tensile strength of the cured product losed obviously when the suberic addition amount is more than 30%.In order to continue to improve the performance of epoxy acrylate and avoid excessive viscosity of the system, the paper selection IPDI, PPG2000 and HEA flexible PUA synthesized and the synthesis and modification of the previous EA suberate blended. Blends thinner selection TPGDA, the amount of 20%, the viscosity can significantly improve the system to ensure fast response speed, and will not damage the mechanical properties of the cured product; photoinitiator chosen 1173 / BP(mass ratio 1: 1) complex system, in an amount of 4%, to a certain extent on the customer oxygen inhibition, get a higher reaction rate and increase the reaction rate of the final conversion; when the addition amount of 30% PUA EA mass, the tensile strength of the cured film 8.5MPa, reached 81.8% before blending modification time, and elongation at break of 130%, improved by 300%, while the loss of mechanical strength significantly increased flexibility is not large; cured film ?max loss factor extremes reached 0.53, compared with unused PUA when Blending improved 39%, ?T is 35.4 ?, when compared PUA Blending unused increase by 56%, good damping properties, enhance the effect is very significant; use 30% PUA Blending After EA, thermal stability, hardness decreased slightly, the volume shrinkage, peel strength improved significantly. |
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