| abstract |
Low-color polyaspartate homopolymers, copolymers or homopolymer/copolymer mixtures and the metal salts thereof, are produced by the oxidative, hydrolysis of polysuccinimide homopolymers, copolymers or homopolymer/copolymer mixtures, and metal salts thereof, in the presence of selected chlorine-free, non-chromogenic oxygen containing oxidizing agents. The preferred oxidizing agents are selected from the group consisting of hydrogen peroxide, sodium percarbonate, potassium percarbonate, sodium perborate tetrahydrate, sodium perborate monohydrate, sodium periodate, potassium periodate and peroxycarboxylic acids. The advantage of the claimed process is that low-color polyaspartates can be produced without the addition of further processing steps beyond the hydrolysis of the polysuccinimide presursor. Solid, low-color polyaspartates are obtained by evaporating to dryness the polyaspartate solutions obtained after oxidative hydrolysis. |