Abstract: Provided is a process useful for making acrylic polymers of methacrylic acid having improved shear stability. The process provides polymers useful as enteric coatings for medicaments having improved coating efficiency of pharmaceutical forms. Also provided are medicaments in solid form coated with said polymers.

Abstract: Provided is a process useful for preparing acrylic polymers of methacrylic acid and ethyl acrylate. The process provides polymers useful as enteric coatings for medicaments in solid form, said coatings having improved effectiveness, reproducibility and coating efficiency. Also provided are medicaments in solid form coated with such polymers.

Abstract: Novel cationic amide compositions having the structure ##STR1## where R.sup.1 represents an alkylene group of the formula C.sub.n H.sub.2n, and alkenyl group of the formula C.sub.n H.sub.n, or a phenyl group, or mixtures thereof, where n equals 0 to 10; R.sup.2 represents C.sub.m H.sub.2m, where m equals 1 to 4; R.sup.3 independently represents methyl, ethyl or propyl; and the combination of R.sup.4 and X.sup.- represents the remnant from a quaternizing agent have been discovered and have been found useful as demulsifiers in breaking petroleum emulsions as might be produced during fireflooding petroleum recovery procedures. In one embodiment, the cationic amide/ester compositions are made by reacting (1) a dicarboxylic acid of the formula: ##STR2## where R.sup.1 represents C.sub.n H.sub.

Abstract: The present invention relates to new compositions and methods of preparation of deflocculents for water-base mud additives. The disclosed materials are low molecular weight terpolymers and graft copolymers consisting essentially of monovalent salts of (1) 5 to 50% by weight of tetrahydrophthalic acid (THPA); (2) 10 to 70% by weight of acrylic acid (AA); (3) 5 to 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid (AMPS); and (4) 0 to 70% by weight of lignosulfonate units. The unique compositions and processes of terpolymers and graft copolymers provide excellent drilling fluid additives which significantly control the viscosity, yield point, gel strength, and fluid loss of drilling fluids over a wide range of temperatures and in the presence of contaminants such as salt, lime, cement, gypsum and drilled solids.