Commercial Poly(aspartic acid) and Its Uses

The demand for biodegradable chemicals is increasing as chemical producers and consumers anticipate more stringent standards for degradability in new and existing products. Poly(aspartic acid) (PAA) is an example of a chemical that shows promise as a biodegradable replacement for polyacrylic acid, a nonbiodegradable polymer that is used in a wide variety of products and applications. In order to meet the potential demand for PAA, we have developed processes for commercial production. These processes utilize solid-phase condensation polymerization of aspartic acid to polysuccinimide in a commercial reactor. The polysuccinimide is then base hydrolyzed to PAA. The performance of PAA made by these methods is comparable and in some cases superior to that of polyacrylic acid in many mineral scale inhibition and particulate dispersion tests. Biodegradation studies of PAA show that it is significantly biodegradable. Preliminary toxicity studies of PAA indicate that it is nontoxic and environmentally compatible.