Synthesis of water-reducible acrylic-grafted polyester resin: Effect of carboxyl content and pH on dispersion stability

Aqueous dispersion of polyester acrylate was synthesized by grafting an acrylic copolymer to an unsaturated polyester and then neutralizing it by an amine. Fumaric acid (FA) was used in different portions in the synthesis of unsaturated polyester (UPE) and then acrylate copolymers were grafted on the unsaturated polyester. The extend of grafting was controlled by changing the amount of FA in UPE chemical structure. The results showed that the particle size of dispersed phase became smaller when more FA was used in UPE formulation. It was found that the sample having 6 mol % of FA in the formulation present a better colloidal stability. It was also revealed that the ratio of UPE to acrylic monomer affected on the colloidal stability of samples. A ratio of 70:30 of UPE to acrylate monomers provide the best colloidal stability. Finally, the effect of neutralization extent on the colloidal stability was investigated. The result showed that a final pH of 8 would be the optimum value for the neutralization extent.

کلیدواژه ها:

water reducible ، dispersion stability ، acrylic graft ، unsaturated polyester