| abstract |
A THIXOTROPE IN THE FORM OF A GELATINOUS PASTE IS PRODUCED BY DISSOLVING A SMALL AMOUNT OF A LIQUID POLYOL IN A LIQUID UNSATURATED POLYESTER RESIN, THEREAFTER ADDING APPROXIMATELY 20 PERCENT BY WEIGHT OF A FINELY DIVIDED GRADE OF COLLOIDAL CLAY, PREFERABLY POWDERED ATTAPULGITE CLAY, AND THEN APPLYING MECHANICAL WORK (SHEAR) TO THE MIXTURE. THE RATIO OF CLAY TO POLYOL IN THE PASTE IS IN THE RANGE OF ABOUT 3 TO 6:1 TO IMPART THIXOTROPY TO A CUT POLYESTER RESIN, THE GELATINOUS PASTE IS ADDED IN AMOUNT SUCH THAT THE CLAY CONTENT OF THE RESULTING THIXOTROPIC COMPOSITION IS LESS THAN ABOUT 3 PERCENT BY WEIGHT AND THE FREE POLYOL CONTENT IS LESS THAN 0.5 PERCENT BY WEIGHT. |