Fluorocarbon Surfactant Modified Polyacrylic Acid And Styrene Maleic Anhydride Copolymer To Prepare Long-Lasting Anti-fogging Coating

Transparent materials have a wide range of applications in product packaging,agricultural film,construction,automobiles and personal protection,but they are prone to fogging,which can affect the effect of the product,even endanger the lives of users.Therefore,the anti-fogging modification of the transparent substrate is of great significance.The traditional super-hydrophilic anti-fog coating has the disadvantages of poor stain resistance and short life.In this paper,the non-ionic fluorocarbon surfactant RfOEG is used to modify PAA and SMA to prepare the long lasting anti-fogging coating.The main contents are as follows:1.Fluorocarbon surfactant RfOEG(perfluoroalkyl polyoxyethylene ether with hydroxyl-terminated structure)was used to to react with acryloyl chloride to synthesize RfPEGA fluorine-containing monomer,it was copolymerized with acrylic acid(AA).And P(AA-co-RfOEGA)copolymers with different mass fractions of RfOEGA were synthesized by adjusting the monomer ratio,and copolymer coatings with different degrees of neutralization(DN)were prepared by spin coating.With the decrease of RfOEGA content and the increase of DN,the anti-fogging property of the coating is enhanced.Although most coatings have antifogging properties,their anti-fogging life is short.In order to obtain a longlasting anti-fogging film,the coating was cross-linked with different crosslinking conditions,and the anti-fog performance of the coating was compared.The results showed that when the mass fractions of P(AA-coRfOEGA),ethylene glycol and Ca(NO3)2 were 10%,10%and 1%,respectively,the coating was cross-linked in 1 wt%TDI solution for 3 min,The obtained coating has the longest anti-fogging life at 40℃,which is 104 days.This is about 350%longer than the anti-fogging life time of the PAA coating under the same conditions,indicating that the copolymer has the potential for preparing long-lasting anti-fogging coatings.2.Through the esterification reaction of styrene-maleic anhydride copolymer SMA and RfOEG,the graft polymer SMA-g-OEGRf with different G.P.was synthesized.Using SMA-g-OEGRf to prepare antifogging coating,the results showed that WCA and OCA increased with the increase of RfOEG G.P.,but the influence on WCA was stronger than OCA.When the G.P.is 20%and the spin coating solution concentration is 0.25 wt%,the switching parameter SP(defined as the difference between the oil contact angle and the water contact angle)achieves the maximum value,which is 35.53°.The water advancing angle is 19.9°,and the water receding angle is approximately 13.1°.AFM characterization shows that the surface roughness of the coating is 23.1 nm,XPS gives a surface fluorine atom percentage of 6.71%,and the thickness of the film is about 36 nm calculated by gravimetric method.Both the rapid hot mist method and the high temperature hot mist method showed that the anti-fogging effect of the coating was good at 95℃.