Study On The Preparation And Connection Properties Of The Tie-coat Resins For The Silicone Antifouling Paint

Organic silicone fouling release coating(SFRC)has the advantages of environmental-friendly and long-term antifouling performance,and it has a broad application prospect.At present,the anticorrosive primer matching with the organosilicone fouling release antifouling coating is usually epoxy system.Due to the poor compatibility and the weak connection ability between the epoxy primer and SFRC,the antifouling coating often falls off which lead to antifouling performance failure.Therefore,it is of great significance to develop a kind of tie-coat matching with SFRC and epoxy primer.In this paper,the anticorrosive primer H44-61 and the antifouling top-coat FRC-725 were taken as the research objects.The surface characteristics and active groups of the primer and top-coat were obtained through infrared spectrum,shore hardness,elastic modulus,surface contact angle and other tests.On this basis,the requirements for the structure and performance design of the supporting tie-coats were also put forward.Based on 5000 c P hydroxy silicone oil as the base matrix and TEOS as the curing agent,the silicone elastomer tie-coat resin was prepared by introducing the amine adhesion promoter and the epoxy adhesion promoter.The experimental results showed that the single additive promoter secondary amine triethoxysilane significantly improved the performance of the tie-coat.And the adhesion strength of the tie-coat to the epoxy primer was up to 2.40 MPa,and the adhesion strength of the tie-coat to the organic silicon top-coat was up to 1.15 MPa.The combination of secondary amine triethoxysilane and epoxy trimethoxysilane have significantly improved the connection performance,and the adhesion strength of the tie-coat to epoxy primer was up to 3.17 MPa,the adhesion strength of the tie-coat to organic silicon top-coat was about 1.00 MPa.Further introducing a small amount of high molecular alkane into the organosilicon elastomer tie-coat resin could change the failure mode of tie-coat from stripping failure to cohesion failure.Silicone physical modified epoxy resin was used as the main matrix,aminosilicone resin and 3-aminopropyltrimethoxysilane(KH-540)were used as the curing agents,and low-viscosity active organosilicon polymer were introduced to prepare silicone-modified tie-coats with excellent connection performance.Its adhesion strength to the top-coat was up to 2.83 MPa.After a small amount of aminobutyronitrile rubber(ATBN)was introduced into the above system,the failure mode of the tie-coat was changed from stripping failure to cohesion failure.The connection mechanism of the tie-coat was studied by solution etching and infrared spectrum characterization.The results showed that the tie-coat and the epoxy primer were mainly formed by the chemical reaction between the amino group and the epoxy group;The tie-coat and the silicone top-coat were formed by the condensation reaction between the alkoxy group or the silicon hydroxyl group.