Synthesis And Properties Of Acrylic Resin Primer Used For PET Film

Biaxially oriented polyester film(BOPET) due to its excellent performance, widely used in the field of optoelectronics. Functional polyester film is mainly through coating with various functional coating on the surface of polyester film, but in the practical application, when coated functional coating directly on the surface of unmodified PET film, adhesion of coating is poor, functional coating is easy to fall off, so it’s need for film surface modification to improve the adhesion. The coating modified modification is a good approach, this method is coated with a layer of resin on the surface of BOPET film, forming a transition layer on its surface to increase the adhesion of film. The main issue is the synthesis of a suitable water-based acrylic resin for improving the adhesion of brightness enhancement film coating on the surface of BOPET films, the main research contents are as follows:Prepared water-based acrylic resin using emulsion polymerization, soap-free emulsion polymerization and solution polymerization respectively, found that the properties of water-based acrylic resin prepared by solution polymerization is the best, consistent with the requirements of optical grade BOPET film coating. The experimental findings with methyl methacrylate, butyl acrylate,2-Hydroxyethyl acrylate, acrylic acid, methyl methacrylate tetrahydrofuran ester and diacetone acrylamide monomers of synthetic resin coating treatment, can be very good to improve the adhesion of brightness enhancement film.Study on the effect of preparation process on the properties of emulsion. Synthetic process are as follows:the 2,2’-Azobis(2-methylpropionitrile) as initiator, the amount of total monomer 1.0wt%; solvent isopropyl alcohol and mass ratio of monomer 2:3; polymerization temperature of 75℃, the heat preservation time is 2 hours; ammonia as neutralization agent.Study on the effect of the amount of each monomer on emulsion preparation and coating adhesion. Found that the hydrophilic monomers of acrylic acid and 2-Hydroxyethyl acrylate, respectively, of the total amount of monomers 6wt% can prepare emulsion of translucent bluish; adding appropriate amount of methacrylic tetrahydrofuran ester and diacetone acrylamide monomer can improve the adhesion; change in the proportion of butyl acrylate and methyl methacrylate to regulate theory of the glass transition temperature of the resin, when theory Tg=10℃, the adhesion performance is the best, reach level 0.Study on the effect of curing agent on the properties of primer. Found that the addition of aziridine crosslinking agent can obviously improve the adhesion performance, and improve the water resistance, the amount of aziridine for acrylic ester emulsion solid content of 6wt%, the best performance.Emulsion particle size analysis concluded that the average particle size of 97.8nm; DSC analysis shows that the actual glass transition temperature of the resin close to the theoretical glass transition temperature; TG analysis shows that the initial decomposition temperature is 389℃, resin thermal stability to meet the requirements of coating.