Patent ID: 7883638
Filing Date: 2011-02-08
Classification: C02F,C23F

Abstract:
1. A method of releasing an additive composition into an open circulating cooling water system comprising placing a controlled release additive composition in contact with an aqueous coolant present in an open circulating cooling water system, the controlled release additive composition comprising: a core comprising an additive component effective as a water treatment in an aqueous coolant of an open circulating cooling water system; and a coating substantially surrounding the core and effective to slow the release of the additive component into an aqueous coolant in the open circulating cooling water system, the coating being insoluble in the aqueous coolant in the open circulating cooling water system, and including a polymeric component selected from the group consisting of (1) polymers including units from vinyl acetate, ethylene and vinyl chloride; (2) polymers including units from vinyl acetate, an acrylate ester, and at least one monomer selected from the group consisting of vinyl neopentanoate, vinyl neohexanoate, vinyl neoheptanoate, vinyl neooctanoate, vinyl neononanoate and vinyl neoundecanoate; and (3) combinations thereof.