Construction And Application Of UV Curing High Wear Resistance Functional Coatings

UV curing technology is widely used due to its fast curing speed,environmental friendliness and wide applicability.Material wear can cause it to be destroyed or even not used properly,causing huge losses.Brushing the wear-resistant coating on the surface of the material can effectively improve the wear and reduce the loss of the material.In this thesis,the organic-inorganic hybrid technology and the synthesis of high-functionality photocurable resin are used to construct a high wear-resistant functional coating.1.Nano-SiO₂was synthesized by sol-gel method using ethyl orthosilicate（TEOS）,deionized water,hydrochloric acid and isopropanol（IPA）as raw materials.The organic phase and the inorganic phase have poor consistency.In order to make the synthesized nano-SiO₂have good consistency in the organic phase,an organic-inorganic hybrid gel is synthesized by using a silane coupling agent such as KH-560.The structure of organic-inorganic hybrid gel was characterized and analyzed by IR.It is added to the resin to prepare a highly wear-resistant transparent composite coating.The effects of different resins,photocuring time,substrate wetting agent and organic-inorganic hybrid gel addition on the properties of the composite coating were investigated.Optimize the experimental scheme to determine the optimal process formula:15%organic-inorganic hybrid gel,35%TMPTA resin,10%3072 resin,34.5%U4237 resin,5.5%photoinitiator and other additives.The composite coating was rubbed with steel wool for 800 times with slight scratches and the hardness was 3H.2.The surface of nano-SiO₂on the market was modified with KH-570,and the structure was characterized and analyzed by IR.Modified SiO₂is added to the resin to prepare a composite coating material.In order to improve the consistency of the modified SiO₂with the organic phase and improve the spraying performance,an ether or ester diluent was added to explore the influence of changing scraping method and curing conditions on the basic properties.The results show that the addition of diluents,the gloss of the composite coating is 92±20,but the wear resistance is reduced;without the addition of diluents scraping,standing at room temperature for 18-22mins,the wear resistance of the composite coating is rubbed with steel wool 1000 times showed slight scratches.3.Surface modification ofα-Al₂O₃with the most commonly used particle sizes of 20μm,30μm,40μm and 50μm on the market is carried out the same manner as the modification of nano-SiO_2.It is added to the resin to prepare a composite coating.The effect of the particle size on the properties of the composite coating was investigated.The results show that the larger the particle size ofα-Al₂O₃,the lower the gloss of the composite coating and the greater the hardness.When the particle size is40μm,the composite coating has the best wear resistance.Composite coating is rubbed with steel wool 850 times showed slight scratches and the hardness is 5H.4.The polypropyl carbonate polyurethane was synthesized in two steps.The first step:synthesizing vinyl functional mono-blocked isocyanate with toluene diisocyanate（TDI）,pentaerythritol triacrylate（PETA）or acrylic acid-β-hydroxyethyl ester（HEA）.Second step:adding polypropylene carbonate polycarboxylate type polyurethane was synthesized from ester diol（Mn=1800）.Structural characterization and analysis were carried out by IR.Optimum reaction conditions and raw material ratio were investigated to prepare a photocurable coating to test the basic properties.The results showed that the first step reaction was40℃,4.5 h;the second step was 70℃,3h.The basic performance of the hexafunctional polyurethane is superior to that of the difunctional polyurethane.The coating is rubbed with steel wool 200 times showed slight scratches.