Preparation And Application Of High Refractive Index UV Curing Resin

In recent years,flexible display technology has developed rapidly,and the requirements for refractive index,light transmittance,flexibility and the like of optical films have become more stringent.In particular,high refractive index,high light transmittance and low viscosity UV resins have good application prospects in optical functional films.Nanoimprinting can enhance the display effect after the surface microstructure design and processing of the optical film,and is a new method for preparing an optical film for flexible display.Under studying the effect of molecular structure on the refractive index of polymers.This paper designs a method for preparing two high refractive index UV resins by using4'4-thiobisthiophenol as matrix and modifying by epoxy acrylate.When the molar ratio of4'4-thiobisthiophenol to epichlorohydrin is 1:20,the catalyst is tetrabutylammonium fluoride,and etherification reaction is carried out at 80^°C for 4 h,and an equimolar ratio of NaOH is continuously added.After the ring closure reaction was carried out at 60^°C for 2 h,the epoxy value of 4'4-thiobisphenylthiophenol epoxy resin was the highest.Under this condition,2%by weight of triethylbenzylammonium chloride is used as a catalyst,and 2%by weight of triethylbenzylammonium chloride is used as a catalyst.n_{-acrylic acid}/n_{-epoxy group}=1.02:1,reaction temperature is 85^°C,the reaction time is 6 h,the comprehensive performance of the EA resin is optimal.the viscosity is 7243 mPa·s?25^°C?,the photocuring time is 20s?365 nm,800 mW/cm²?,the refractive index is 1.633,the flexibility is 6 grades,the pencil hardness is B,and the 450 nm wavelength transmittance is 84.1%.The light rate is 89.75%?25?m?.Under such conditions,2%wt dibutyltin dilaurate is used as a catalyst,1%wt 4-methoxyphenol is used as a polymerization inhibitor,n_-NCO/n_{-epoxy group}=0.85:1,reaction temperature is 85^°C,reaction time is 4 h,the epoxy resin obtained the AOI resin with oxazolidinone structure has the best comprehensive performance.the viscosity is5326 mPa·s?25^°C?,the photocuring time is 20 s?365 nm,800 mW/cm²?,the refractive index is 1.667,the flexibility is 4 grades,the pencil hardness is 2H,and the 450 nm wavelength transmittance is 87.15%.The light rate is 96.97%?25?m?.Through the test of UV performance of different reactive diluents,when EA:OPPEA:HDDA:TMPTA=10:2:1:1?prepolymer content:71.4%?,the refractive index of EA-UV resin is 1.60,the light transmittance at 450 nm is 86.41%,and the viscosity is 2431 mPa·s?25^°C?.The curing shrinkage rate of 5.12%,has a T_g of 107^°C,with 1%weight loss temperature at 153.60^°C,flexibility is 7 grades,tensile strength is 4.28 MPa,and elongation at break is 5.71%.When AOI:OPPEA:DPGDA:TMPTA=10:1:1:1?prepolymer content76.92%?,the refractive index of AOI-UV resin is 1.644,the light transmittance at 450 nm is88.81%,the viscosity is 2438 mPa·s?25^°C?.The curing shrinkage is 4.84%,has a T_g of116^°C with 1%weight loss temperature at 200.09^°C.Flexibility is grade 6,tensile strength is 6.13 MPa,and elongation at break is 4.37%.Finally,the surface patterning treatment of AOI-UV resin by nanoimprinting showed that the UV resin has the potential to be applied to the anti-reflection film and anti-coun-terfeit glare film.