Production of Waterborne Alkyd-Acrylic Hybrid Latexes with Controlled Polymer Architecture and Nanoparticle Morphology

MINARI, ROQUE J; GOIKOETXEA, MONIKA; BERISTAIN, ITXASO; PAULIS, MARÍA; BARANDIARAN, MARÍA J.; ASUA, JOSÉ M.

Los Cocos - Argentina

Simposio; V Simposio Argentino-Chileno de Polímeros; 2009

Comite Organizador

Waterborne alkyd-acrylic coatings have the potential to combine the positive properties of the alkyd resins (e.g., auto-oxidative curing, high gloss and penetration in wood) with the fast drying and color retention of acrylic latexes. The drawback of alkyd resins, which are tackiness and the need to be dissolved in organic solvent, can also be avoided. The improvement of properties is expected to be maximum with intimate contact of both materials. Unfortunately, alkyd and acrylic polymer are not compatible. In this way, miniemulsion polymerization allows the incorporation of hydrophobic components, like alkyd resins, into polymer particles, because mass transfer through the aqueous phase is avoided. Formulation and polymerization conditions affect the extent of the alkyd-acrylic compatibilization. In addition, the amount and distribution of the acrylic homopolymer, the free resin and the grafted copolymer is an issue of concern in hybrid systems and determines the nanoparticle morphology which strongly influences the properties of the hybrid materials. In this work, the miniemulsion polymerization used to synthesize waterborne acrylic-alkyd nanocomposites and the effect of the process variables on the polymer architecture (molecular weight, acrylic and resin degree of grafting) and particle morphology were investigated.