Study On The Synthesis Of Hydroxyl Acrylic Resin Emulsion

With the national and public attention to environmental protection gradually increased,the traditional solvent-based coatings have been limited,people tend to use environmentally friendly low VOC paint.Waterborne acrylic polyurethane coatings combine the advantages of polyurethane coatings and acrylic emulsions,while overcoming both weaknesses,and their application areas are fairly extensive and are increasingly valued by people.Waterborne acrylic polyurethane coating is composed of isocyanate curing agent and acrylic acid polyol.The acrylic acid emulsion in acrylic polyol has become a hotspot because of its environmental protection,simple synthesis process,easy availability of raw materials and low cost.Experiments were carried out using methyl methacrylate(MMA),n-butyl acrylate(BA),acrylic acid(AA)and hydroxyethyl methacrylate(HEMA)as polymerization monomers,using anionic,nonionic emulsifier,Ammonium(APS)as initiator to prepare a hydroxyl acrylic acid emulsion with good performance.The self-made hydroxyl acrylic acid emulsion was mixed with the Bayer water-based polyisocyanate curing agent 2655 and 304 to form a resin coating on the board.The effects of polymerization process and formulation on the emulsion and resin coating were investigated.The results were as follows: When the anionic emulsifier PCA078 and the polymerizable nonionic emulsifier ER30 were used in accordance with the mass ratio of 1: 2 as the emulsifying system,the amount of emulsifier used is 2.5% of the total mass of the monomer,the polymerization temperature is controlled from 83 ° C to 86 ° C,the initiator dosage is between 0.4% and 0.5% of the total mass of the monomer,the hydroxyl content is about 2% of the total mass of the monomer and the amount of AA is 2.5% of the total mass of monomer,the resulting hydroxyl acrylic emulsion has excellent performance.The self-made hydroxyacrylic emulsion and the Bayer 2655 are excellent in the performance of the coating film when mixed with n(NCO)/ n(OH)1.5: 1.The FT-IR shows that all the monomers used in the experiment have taken part in the reaction and the crosslinking reaction of water based isocyanate curing agent and self-made hydroxy acrylic emulsion has been formed.The DCS shows that Tg of the synthesized emulsion meets the expectation.The TGA shows that the coating has excellent thermal stability and has two components.The DLS shows that the particle size of the synthesized emulsion is smaller and the particle size distribution is uniform.