Method for obtaining water-based paints using expanded polystyrene (EPS) waste and/or extruded polystyrene (XPS) waste as raw material

A process for obtaining water-based paints using waste expanded polystyrene (EPS) and/or extruded polystyrene (XPS) as raw material, comprising:

• a) cleaning EPS and/or XPS waste with a surfactant to remove organic matter;
• b) rinsing and removing all surfactants and solvents used for cleaning;
• c) treat the EPS and/or XPS waste from step (b) with an organic solvent until obtaining a first mixture with a concentration of EPS and/or XPS in the organic solvent of between 20 and 80% w/w;
• d) decanting impurities from the mixture obtained in step (c) for a period of time between 24 hours to 120 hours;
• e) collecting a supernatant obtained from step (d);
• f) making a second mixture of the supernatant obtained in step (e) with emulsifier and then water;
• g) carrying out a pigment dispersion in the second mixture obtained in (f), for 5 to 50 minutes at a speed between 500 and 3,000 rpm and at a temperature between 2° and 90° C.;
• h) mixing the product of step (g) with water, between 200 and 2,000 rpm, until achieving a mixture of organic solvent water in a ratio between 4:1 and 2:3.