Study On Matt Polyurethare Acrylic Oligomers By Ultraviolet(UV) Curing

In recent years, as the country’s increasingly stringent environmental requirements, UV curing technology was widely applied in wood coatings and the trend is still inspiring. However, some practical application problems came up with the fast development of UV-curable wood coatings. For matte coatings, many of those coatings who gain matt through adding matting agents would cause some problems. Poor arrangement of extinction, for example, will result in extinction difficulties, gloss instability and the surface floating of the film and other problems. This study aims to use UV-curable Polyurethane acrylic oligomers that can be used to prepare high-hardness matt UV-curable wood coating resins to reduce or eliminate the use of extinction powders,making matt UV-curable wood coatings better to apply. In this paper, the analysis of Polyurethane acrylic oligomers and the screening and research of various components in UV curing coatings, as well as the determination of a number of application properties of the cured film;explore a variety of factors affecting the performance of the film; And the principle of Polyurethane acrylic oligomers extinction was discussed. The results are as follows:1 .UV monomer on the UV-curable coatings viscosity, curing efficiency, paint gloss and curing shrinkage and other properties have an impact. Taking into account the overall amount of UV monomer set at 30-50%, TPGDA and TMPTA each use half.2. Photoinitiator on the UV-curable coating curing efficiency, film hardness, paint luster and so on. The amount of TPO used in the photoinitiator is between 2-4%.3. The thickness of the film has an effect on the cure rate and paint gloss. The thickness of the coating film is about 20 μm.4. Using PUA oligomer of Wanhua Beijing as the main resin of UV-curable coating formula, adding 50%; TMPTA and TPGDA as UV monomer; adding 25% each; the use of photoinitiator TPO as UV-curable coatings formulation of the photoinitiator, adding 3%; adding BYK-333 as a leveling agent to improve the surface smoothness of the film; without extinction powder, UV-curable coatings film can also be a good extinction effect.5. The various properties of the UV-curable coatings synthesized by the PUA oligomers are excellent and can be used for practical use.6. The mechanism of film extinction was studied preliminarily.Under the slow curing, the surface of the paint film should form a heterogeneous structure with large molecular weight difference, and the compatibility between the film and the film will produce the final film.