Patent ID: 6069217
Filing Date: 2000-05-30
Classification: C08G,G03F

Abstract:
A urethane-acrylic thickening composition for aqueous systems produced as a reaction product synthesized in two steps:i) first by producing a prepolymer comprised of the reaction product of:a) one or more polyisocyanates having at least two isocyanate groups per molecule;b) one or more polyether polyols having the repeat unit ##STR10## where R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are independently selected from the group consisting of H, CH.sub.3 and C.sub.2 H.sub.5, including polyether polyol polymers and copolymers of ethylene glycol, propylene glycol or butylene glycol, and mixtures thereof;c) a capping agent comprising one or more linear or branched aliphatic, cycloaliphatic or aromatic compounds containing a single active functional group selected to be reactive with an isocyanate or active hydrogen end group,d) a connecting link, which also acts as a capping agent, having a polymerizable double bond and a single active moiety having the structure ##STR11## where R.sub.1, R.sub.2 and R.sub.3 are independently selected from the group consisting of hydrogen, a linear or branched, aliphatic or aromatic chain containing from 1 to 30 carbon atoms, and carboxylic acid --COOX where X is hydrogen or an alkali, ammonium or amino group or a linear or branched, aliphatic or aromatic chain containing from 1 to 30 carbon atoms andR.sub.4 is selected from the group consisting of linear or branched, aliphatic or aromatic chains containing from 1 to 30 carbon atoms, a repeat unit as defined in b) and copolymers thereof, andA is hydroxyl, a primary or secondary amino group, allyl alcohol, ethoxylated allyl alcohol, propoxylated allyl alcohol, allyl alcohol surfactants, and mixtures thereof, and;ii) when the prepolymer is formed, reacting the prepolymer with the following components:e) one or more C.sub.3 -C.sub.8 a, b-ethylenically unsaturated carboxylic acid monomers; andf) one or more copolymerizable nonionic vinyl monomers, thereby producing said urethane-acrylic thickening composition.