Watercolor Conversion to Gouache

I use very inexpensive watercolor paints ( from eBay) and dissolve in warm water over 15 minutes.

I mix the solution with polyethylene glycol-8000 and kaoline clay powder along with a polycitrate ester ( previously prepared from citric acid and dipropylene glycol ( thermal condensation in a small convection oven at 175 deg.C  . The citrate ester polymerization is stopped before the cooled polymer is no longer soluble in water.