Study On Preparation And Properties Of UV-curing Hydrophilic Anti-fogging Acrylate Coatings

Antifogging coating is a functional coating used to prevent fogging or moisture condensation on the surface of transparent substrates.In general,antifogging coatings are mainly divided into inorganic antifogging coatings,organic antifogging coatings and organic-inorganic hybrid antifogging coatings.Due to the inorganic antifogging coatings have some limitations for application and organic antifogging coatings are easily damaged by water with poor adhesion on the substrate.Based on the organic-inorganic composite technology and UV curing technology,in this paper,the nanosilica containing thiol groups was prepared by sol-gel method via condensation reaction between Si-OH of 3-mercaptopropyl trimethoxysilane(KH590)and nanosilica.And two antifogging coatings with different matrix resin systems were prepared by using bisphenol A expoxy acrylate and polyurethane acrylate as the matrix resin,using ACMO,HEMA,HDDA and TMPTA as the diluenting agent,using polyethylene glycol monoacrylate as the hydrophilic monomer,using photoinitiators 184D and photoinitiators 819 as the compound photoinitiators.And the properties of the modified nanosilica and the two antifogging coatings were characterized and tested.The results showed that the average particle size of the modified nanosilica was 151.6 nm and the relative grafting rate was 16.3%.Compared with the unmodified nanosilica,the average particle size of the modified nanosilica was obviously smaller.The dispersibility in the organic system was greatly improved.The organic-inorganic antifogging coating of epoxy acrylate system has good performance of smooth appearance,excellent antifogging property,water contact angle of 8.9°,pencil hardness of 2H,adhesion of 0 grade,certain rub resistance and good water resistance,which can pass the testing of hot and cold cycle,high hot humidity test,20 times of water flushing.The transmittance compared with blank transparent substrate is higher than 2.7%.The organic-inorganic antifogging coating of polyurethane acrylate system has good performance of smooth appearance,excellent antifogging property,water contact angle of 13.8 °,pencil hardness of H,adhesion of 0 grade,good rub resistance and water resistance,which can pass the testing of hot and cold cycle,high hot humidity test,25 times of water flushing.The transmittance compared with blank transparent substrate is higher than 3.3%.