Preparation of an acrylics-grafted polyester and its aqueous dispersion

Abstract

An investigation was undertaken to develop a new class of water-borne polyesters having excellent dispersibility without using emulsifiers. Grafting reactions of hydrophilic acrylics to polyesters and the relationships between reaction conditions and the dispersion diameters are discussed. Aqueous dispersions of particles having small diameters were obtained by use of an unsaturated polyester. Particle diameters were related to the grafting efficiency that could be enhanced by copolymerization of reactive monomers with the unsaturated bonds of polyesters. The relationships between particle diameters and the kind of acrylic monomers were described by the copolymerization reactivity ratio of the unsaturated polyester and acrylic monomers. Also, the influences of the solvency of the reaction medium and the influence of concentration of unsaturated bonds of the polyesters in the reaction medium were discussed to explain the low reactivity between the unsaturated bonds and acrylic monomers.

Preparation of an acrylic-grafted polyester and its aqueous dispersion: Grafting utilizing alternating copolymerization

“…In our previous article, 10 we reported that the grafting of P(St-AA) to unsaturated polyester often caused a gel. In this article, the relationship between the particle diameters and the grafting conditions is examined in detail.…”

“…The conversions of the fumarate unit in the polyester were determined by use of 1 H-NMR. 10 Table V shows the results of the comparison.…”

“…In our previous article, 10 we reported the grafting reactions of acrylic acid and other monomers to polyesters and the relationship between reaction conditions and the dispersion diameters. Aqueous dispersions of particles having small diameters were obtained by use of unsaturated polyester.…”

Applications for Automotive Coatings

“…They consist of "core-shell" particles with a core of high molecular weight polyester. Small particle diameters were obtained by use of polyesters having the largest amount of unsaturated bonds unless gelation occurs [24][25][26][27][28][29][30]. Thermosetting water based polyester resin coating composition prepared from polyalkadienediol may be directly applied to wet electrodeposited coating [31].…”

In Coatings, Adhesives, and Laminates

“…Alternatively, water dispersibility can be achieved via the grafting of hydrophilic acrylics onto the polyester. The solvency of the reaction medium, concentration of unsaturated bonds, and the reactivity ratios of unsaturated polyesters with acrylic monomers strongly infl uence the particle size [22] .…”