Interactions In Coating Colors Containing Clay, Latex, and Starch, 1996 Coating Conference Proceedings
The adsorption and rheological behaviour of a phosphate starch ester and a hydroxyethyl starch ether in clay/latex coating colours are compared. Adsorption of both derivatives occurred onto kaolin, but differing behaviours were observed. Phosphate starch adsorption was reduced by the addition of polyacrylate dispersant, whilst adsorption of the hydroxyethyl starch was insensitive to polyacrylate. Preferential adsorption of the amylose component was detected with the latter derivative. Styrene-butadiene latex suspensions were destabilised by the addition of phosphate starch, but not the hydroxyethyl derivative. This was also found in the presence of clay. Rheological studies suggested that the structuring effect of the phosphate starch with clay suspensions is greater than the hydroxyethyl starch. The colours displayed elastic behaviour which may be linked to film-split problems during roll coating, for example.
Interactions In Coating Colors Containing Clay, Latex, and Starch, 1996 Coating Conference Proceedin