| Veneer and finish foil were two kinds of wood-based panel cover materials. Their characteristic was that they can be decorated with curved surface, and the surface of the decorative pattern to show the effect of natural solid wood. Due to the superior performance, the solvent based coating has been the first choice of the paint coating. However, a large number of volatile organic gas (VOC) released in the process of preparation and use, it brought serious harm to the environment and humans’health. With the improvement of people environmental protection consciousness and the Formulation of relevant laws, the traditional solvent based coating was gradually replaced by new environmental protection coating. Water-based coating was an important part of the new environmental protection coating.In this study, the room temperature curing coatings used for veneer and the baking curing coating used for finish foil were prepared,and the performance of coatings were been analyzed.The coating used for veneer was thermosetting coatings consisting of water-based hydroxyl acrylate emulsion and isocyanate. After selection of the water-based hydroxyl acrylate on the market, three kinds of water-based hydroxyl acrylate were chosen to prepare coating with the isocyanate. After the coating film performance testing, the best hydroxyl acrylate was used as the main film-forming material. Studied the effect of the molar ratio of -NCO/-OH on the paint film property, the result showed that the optimum molar ratio of -NCO/-OH was 1.3 and this kind of two-component waterborne wood lacquer can form film at room temperature. The performance test showed that the coating had good performances including alcohol resistance, alkali resistance, stain resistance, dry and wet and heat resistance, and high hardness. FTIR had been used to characterize the changes of the structure of acrylic before and after the curing.Amine/acrylate baking paint was used in finish foil. The water-based hydroxyl acrylate was chosen as the main film-forming material and some methyl etherification melamine was used as curing agent. The amine/acrylate baking coating was prepared by adding the right amount of various additives. The performance of the coating passed the relevant tests when it was baked at 140℃ and the ratio of the solid mass of amine/acrylate was 0.27/1. The changes of the structure of amine/acrylate before and after reaction were analyzed by infrared spectroscopy. The thermal properties of the coating were analyzed by the differential scanning calorimeter and thermogravimetry.The water-based hydroxyl acrylic emulsion in the market for paint paper amine/acrylate coatings has many problems including the low solid content, the short activation period and the poor chemical resistance. In order to improve the property of amine/acrylate baking paint, the acrylate monomers were used to synthesize water-based hydroxyl acrylic emulsion by emulsion polymerization. The water-based hydroxyl acrylic emulsion which had 50% solid content with good chemical resistance and long activation period was obtained by the optimizations of the dosage of emulsifier, the dosage of initiator and the amount of acrylic acid. The comparison of the water-based hydroxyl acrylic emulsion in this study and the other water-based hydroxyl acrylate from the market showed that the performance of the stoving varnish made by the different water-based hydroxyl acrylic emulsion is similar. The particle size of water-based hydroxyl acrylic emulsion was analyzed by ZetaPALS particle size analyzer. The structure of water-based hydroxyl acrylic emulsion was characterized by infrared spectrum. |
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