| Water-borne UV-curable coating for fast curing speed, film with excellent performance, environment friendly and energy saving, low cost of base material of excellent performance has been high-speed development in the past 20 years, is oriented to green products of the 21st century.This experiment has four different synthesis of UV-curable polyurethane acrylates resins, respectively numbers for WPUA-1, WPUA-2, WPUA-3, WPUA-4. WPUA-1 resin is synthesized by polypropylene glycol (PPG), toluene diisocyanate (TDI), dimethylol propionic acid (DMPA), hydroxyl ethyl acrylate (HEA) for monomer by stepwise way; WPUA-2 resin is synthesized by polyester glycol (PHA) instead of polyether glycol (PPG) by stepwise way, and other monomers is constant; WPUA-3 resin is synthesized by hydrophilic glycol (M-T) instead of DMPA by stepwise way, and other monomers is constant; WPUA-4 resin is synthesized by polypropylene glycol (PPG), toluene diisocyanate (TDI), dimethylol propionic acid (DMPA), hydroxyl ethyl acrylate (HEA) for the monomer by one-step way. This article mainly discusses properties of WPUA-1 resin and emulsion, and compares the properties of four kinds of resins and emulsions. This paper discusses WPUA-1 system, the hydrophilic group content, neutralizer type and neutralizer content, the degree of neutralization on the hydrophilicity of the resin and the appearance and stability of the emulsion, as well as prepolymer molecular design, photoinitiator type, photoinitiator, dry condition, neutralization degree, and solid content of the emulsion on the curing speed of the coating; the same time, mechanical properties and resistance to chemical reagents of the cured film of WPUA-1 are determined, the final test inspects effect of the high-branched polyester volume on curing rate and mechanical properties of the film of WPUA-1.The results show that:In WPUA-1 system, when the amount of-COOH is 0.61 mmol, emulsion is stable translucent blue, which latex average particle size is 42nm, curing speed of the coating is the fastest, mechanical properties of cured film properties and resistance to chemical reagents are the best; Using triethylamine as the neutralizer, the neutralization degree of 90%, Water dispersion of the resin is the best; Hydroxyanisole is used as the inhibitor, total mass fraction of resin 5‰, methyl ethyl ketone is used as the solvent, adding volume to 10mL in the resin process, dibutyltin dilaurate is used as the catalyst, the synthesized resin and emulsion stability is good; n(PPG):n(TDI) for 1:3, photoinitiator for the 819-DW, total mass fraction of emulsion 3%, the neutralization degree of 90%,40% solid content of the emulsion, coating film dried at 80℃for 2min, the coating curing speed is the fastest; Addition of high-branched polyester for 10%, coating film curing rate and coating mechanical properties of WPUA-1 are bother improved greatly; In the four different systems, WPUA-1, WPUA-2, WPUA-3, WPUA-4, WPUA-1 system has the best comprehensive properties. |
