Study On Synthesis Of Modified Waterborne Alkyd Resin And Its Application;study On Synthesis Of Modified Waterborne Alkyd Resin And Its Application

With people's consciousness for environment protection, more attentions had been focused on the environmentally friendly coating. The research and application of water-borne coating had becoming one of the main fashions in coating industry. As one of the environmentally friendly resins, water-borne alkyd resin had greatly scientific vestigational value, bright applied foreground, and great social and economical benefits. However the waterborne alkyd resin had some disadvantages, such as a lower surface hardness, which restricted its application. The formulation and production technology of the modified waterborne alkyd resin and its alkyd-amino paint had been investigated previously. In the paper, the influences of the Oil degree, the final acid value, benzoic acid (BA) concentration, trimellitic anhydride (TMA) content, fatty oil and polyol type on the properties of alkyd resin and coating film were discussed. Using hexamethoxymethyl melamin (HMMM) as cross-linking agent, the modified waterborne alkyd-amino paint presented good propertie, and its general performance could reach or exceed those of traditional solvent-borne coating, indicating that the paint could be used directly on the surface of iron products. Moreover, the paint could be an environment friendly coating.In the paper, the waterborne alkyd resin was prepared through melting esterifaction and salified method, based on castor oil, isophthalic acid (IPA), TMA, trimethylolpropane (TMP). The waterborne alkyd resin presented good water-solublilty, stability and other performance when the final acid value of the waterborne alkyd resin was 50~55 mgKOH·g-1 and its oil degrees was 35~40%.BA was utilized as the modifier to enhance the film hardness and the structure of waterborne alkyd resin was also characterized by infrared spectroscopy. The results showed that resin with good performance could be obtained when BA concentration was 6% and TMA content was 10%. Some experiments for the optimization of cosolvent and neutralizer were also performed. The modified waterborne alkyd resin presented good water-solublilty and stability. Because the effect of BA-modified water-soluble alkyd resin was superior and the material was facile, it was expected for widely application in the future.Finally, using hexamethoxymethyl melamin (HMMM) as cross-linking agent, some experiments for the optimization of Paint additives and production technology were performed, the modified waterborne alkyd-amino paint with good adhesion, hardness up to 3 H and gloss 95 could be obtained. The general performance of the paint could reach or exceed those of traditional solvent-borne paint.