Effect of coalescents on properties of protective styrene-acrylate latex coatings of oriented particle chipboards

Abstract

It is necessary to note that in the production of finishing and protective materials for the surfaces of oriented chipboards, the most effective film former today is considered to be styrene-acrylate latex. However, the known styrene-acrylate dispersions have a minimum film formation temperature within 14–20 ° C, which doesn’t satisfy mass construction works. In order to obtain high-quality films in a wide range of temperatures, it is necessary to use special additives - coalescents. It was decided to use methoxypropanol, ethylene glycol and butyl glycol as coalescents. Their main selection criterion was the homogeneity of the resulting film and the absence of external defects. Based on the studies conducted, it was determined that the butyl glycol additive in the composition leads to the reduction in the elastic modulus of film coatings, which, in its turn, invariably leads to the increase in the relative elongation at break. The butyl glycol additive also enhances the film-forming and adhesive properties of styrene-acrylate latexes. According to the results of the experiments a composition with 4% wt. butyl glycol content as a coalescent was selected for further research.