Water dispersible, modified polyurethane thickener with improved high shear viscosity in aqueous systems

A water dispersible modified polyurethane thickener for aqueous compositions which is the reaction product of:

• a) polyisocyanate;
• b) polyether polyol in an amount ranging from about 0.10 to about 10.00 moles per mole of polyisocyanate;
• c) modifying agent having at least two active hydrogen moieties and at least one pendant hydrophobic group, said pendant hydrophobic group having at least 12 carbon atoms and having no moieties reactive with the polyisocyanate or the polyether polyol;
• d) a second type of modifying agent having the formula:
• X.sub.x --R--Y.sub.y
• wherein R represents a group containing from 0 to 10 carbon atoms, X and Y represent a group containing at least one active hydrogen moiety independently selected from the group consisting of primary amino, secondary amino, carboxyl, hydroxyl, mercapto and mixtures thereof, x and y is at least I and the sum of (x+y) is at least 2, wherein the second type of modifying agent does not have a pendant hydrophobic group and wherein the total amount of c) and d) is from about 0.015 to about 3.400 moles per mole of polyisocyanate;
• and
• e) capping agent which is reactive with the reaction product of the polyisocyanate, the polyether polyol, the modifying agent in an amount sufficient to cap the reaction product, said water dispersible modified polyurethane thickener having improved high shear rate viscosity efficiency compared to a polymer which does not contain the modifying agent with said pendant hydrophobic group.

A water dispersible modified polyurethane thickener for aqueous compositions which is the reaction product of:

• a) polyisocyanate selected from the group consisting of 1,6-hexamethylene diisocyanate, 1-isocyanate-3-isocyanatomethyl-3,5',5-trimethylcyclohexane, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate and mixtures thereof;
• b) polyether polyol in an amount ranging from about 0.10 to about 10.00 moles per mole of polyisocyanate, said polyether polyol having an average molecular weight in the range of from about 1,500 to about 20,000 and having the repeating unit ##STR10## wherein 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 ;
• c) modifying agent in an amount ranging from about 0.015 to about 3.400 moles per mole of polyisocyanate, said modifying agent having at least two active hydrogen moieties and at least one pendant hydrophobic group, said pendant hydrophobic group having at least 12 carbon atoms and having no moieties reactive with the polyisocyanate or the polyether polyol;
• and
• d) capping agent which is reactive with the reaction product of the polyisocyanate, the polyether polyol and the modifying agent and which is present in an amount sufficient to cap the reaction product of the polyisocyanate, the polyether polyol and the modifying agent, said water dispersible modified polyurethane thickener having improved high shear rate viscosity efficiency compared to a polyurethane which does not contain the modifying agent with said pendant hydrophobic group.

A water dispersible modified polyurethane thickener for aqueous compositions which is the reaction product of:

• a) polyisocyanate selected from the group consisting of 1,6-hexamethylene diisocyanate, 1-isocyanate-3-isocyanatomethyl-3,5',5-trimethylcyclohexane, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate and mixtures thereof;
• b) polyether polyol in an amount ranging from about 0.10 to about 10.00 moles per mole of polyisocyanate, said polyether polyol having an average molecular weight in the range of from about 1,500 to about 20,000 and having the repeating unit ##STR11## wherein 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 ;
• c) modifying agent having at least two active hydrogen moieties and at least one pendant hydrophobic group, said pendant hydrophobic group having at least 12 carbon atoms and having no moieties reactive with the polyisocyanate or the polyether polyol;
• d) a second type of modifying agent having the formula:
• X.sub.x --R--Y.sub.y
• wherein R represents a group containing from 0 to 10 carbon atoms, X and Y represent a group containing at least one active hydrogen moiety independently selected from the group consisting of primary amino, secondary amino, carboxyl, hydroxyl, mercapto and mixtures thereof, x and y is at least 1 and the sum of (x+y) is at least 2, wherein the second type of modifying agent does not have a pendant hydrophobic group and wherein the total amount of c) and d) is from about 0.015 to about 3.400 moles per mole of polyisocyanate;
• and
• e) capping agent which is reactive with the reaction product of the polyisocyanate, the polyether polyol, the modifying agent and the second type of modifying agent and which is present in an amount sufficient to cap the reaction product, said water dispersible modifier polyurethane thickener having improved high shear rate viscosity efficiency compared to a polymer which does not contain the modifying agent with said pendant hydrophobic group.

A method of preparing a water dispersible modified polyurethane thickener for aqueous compositions which is the reaction product of:

• a) polyisocyanate;
• b) polyether polyol in an amount ranging from about 0.10 to about 10.00 moles per mole of polyisocyanate;
• c) modifying agent in an amount ranging from about 0.015 to about 3.400 moles per mole of polyisocyanate, said modifying agent having at least two active hydrogen moieties and at least one pendant hydrophobic group, said pendant hydrophobic group having at least 12 carbon atoms and having no moieties reactive with the polyisocyanate or the polyether polyol;
• and
• d) capping agent which is reactive with the reaction product of the polyisocyanate, the polyether polyol and the modifying agent and which is present in an amount sufficient to cap the reaction product of the polyisocyanate, the polyether and the modifying agent,
• said method comprising;
• i) adding polyisocyanate to polyether polyol to form a reaction mixture;
• ii) adding capping agent to the reaction mixture;
• and
• iii) adding modifying agent to the reaction mixture so as to form the water dispersible modified polyurethane thickener said water dispersible modifier polyurethane thickener having improved high shear rate viscosity efficiency compared to a polyurethane which does not contain the modified agent with said pendent hydrophobic group.

A method of preparing a water dispersible modified polyurethane thickener for aqueous compositions which is the reaction product of:

• a) polyisocyanate;
• b) polyether polyol in an amount ranging from about 0.10 to about 10.00 moles per mole of polyisocyanate;
• c) modifying agent in an amount ranging from about 0.015 to about 3.400 moles per mole of polyisocyanate, said modifying agent having at least two active hydrogen moieties and at least one pendant hydrophobic group, said pendant hydrophobic group having at least 12 carbon atoms and having no moieties reactive with the polyisocyanate or the polyether polyol;
• and
• d) capping agent which contains a single active hydrogen group, and is reactive with the reaction product of the polyisocyanate, the polyether polyol and the modifying agent and which is present in an amount sufficient to cap the reaction product of the polyisocyanate, the polyether and the modifying agent,
• said method comprising;
• i) mixing the polyether polyol and capping agent;
• ii) adding the polyisocyanate to the mixture;
• and
• iii) adding modifying agent to the mixture so as to form the water dispersible modified polyurethane thickener, said water dispersible modified polyurethane thickener having improved high shear rate viscosity efficiency compared to a polyurethane which does not contain the modifying agent with said pendant hydrophobic group.