Lyondell Chemical Technology, L.p.

Arco Chemical Technology, L.p.

Robert M Arrell

Frank J Liotta, Jr

Steven A Schwartz

Sallie J Lee

Beth M Steinmetz

A gypsum composition comprising water, stucco, clay, an amine compound, a polyoxyalkylene, and a comb-branched copolymer is disclosed. The gypsum composition has improved fluidity. A method for preparing the gypsum composition is also disclosed. The method comprises mixing the components to form a slurry, casting the slurry into a product, and drying the product.

Gypsum composition

A two-step, base-catalyzed process for making crosslinked polyvinylpyrrolidone (PVP-P) having a low swell volume is disclosed. A crosslinker is generated &ldquo;in situ&rdquo; in the first step by heating a basic aqueous mixture containing a relatively low concentration of N-vinylpyrrolidone under added inert gas pressure. In a second step, the reactor temperature is reduced to initiate polymerization. The process is a productive way to make PVP-P that is easy to isolate and purify. The polymer has a swell volume less than about 40 mL H O/10 g polymer, which makes it valuable for beverage clarification.

Growing community of inventors

Quarryville, PA, United States of America

Robert M Arrell