Suppression of aqueous viscosity of nonionic associative thickeners
View Patent ↗A composition is composed of a hydrophobically modified aminoplast polyether or hydrophobically modified non-urethane polyethers with a viscosity suppressing agent of cyclodextrins or derivatives thereof. A method for improving the pumpability and pourability of aqueous solutions of thickener of a hydrophobically modified aminoplast polyether or hydrophobically modified non-urethane polyethers which is provided by admixing a cyclodextrin with the thickener to form a complex of the cyclodextrin and thickener where the viscosity of the thickener is suppressed and adding the complexed admixture to an aqueous system containing a water-insoluble polymer wherein the cyclodextrin is decomplexed and the thickener becomes an effective thickener. An example of the uses for this composition and method is in film forming coatings such as latex paints.
1. A composition comprising
a) a hydrophobically modified aminoplast polyether or a hydrophobically modified non-urethane polyether product and
b) a viscosity suppressing agent selected from the group consisting of cyclodextrins and derivatives thereof,
wherein the lower limit of the solids content of the polymer is 10 wt %.
2. The composition of claim 1 , wherein the cyclodextrins are selected from the group consisting of alpha (α), beta (β), and gamma (γ) cyclodextrins.
3. The composition of claim 1 , wherein the cyclodextrin derivatives are selected from the group consisting of methylated, hydroxyethytated, hydroxypropylated, carboxymethylated, and diaminoethylated cyclodextrins.
4. The composition of claim 1 , wherein the lower limit of the hydrophobe types has 8 carbons.
5. The composition of claim 1 , wherein the lower limit of the hydrophobe types has 10 carbons.
6. The composition of claim 1 , wherein the lower limit of the hydrophobe types has 12 carbons.
7. The composition of claim 1 , wherein the upper limit of the hydrophobe types has 40 carbons.
8. The composition of claim 1 , wherein the upper limit of the hydrophobe types has 28 carbons.
9. The composition of claim 1 , wherein the upper limit of the hydrophobe types has 18 carbons.
10. The composition of claim 1 , wherein the upper limit of the solids content of the polymer is 50 wt %.
11. The composition of claim 1 , wherein the upper limit of the solids content of the polymer is 25 wt %.
12. The composition of claim 1 , wherein the upper limit of the solids content of the polymer is 20 wt %.
13. The composition of claim 1 , wherein the lower limit of the cyclodextrin content is 0.2 wt %.
14. The composition of claim 1 , wherein the lower limit of the cyclodextrin content is 0.5 wt %.
15. The composition of claim 1 , wherein the lower limit of the cyclodextrin content is 0.7 wt %.
16. The composition of claim 1 , wherein the upper limit of the cyclodextrin content is 7.0 wt %.
17. The composition of claim 1 , wherein the upper limit of the cyclodextrin content is 3.0 wt %.
18. The composition of claim 1 , wherein the upper limit of the cyclodextrin content is 1.5 wt %.
19. The composition of claim 1 , wherein the solids content of the polymer is 20 wt % and the cyclodextrin content is 1.0 wt %.
20. The composition of claim 1 , wherein the solids content of the polymer is 17 wt % and the cyclodextrin content is 3.0 wt %.
21. A process for preparing the composition of claim 1 comprising dry blending a hydrophobically modified aminoplast polyether or hydrophobically modified non-urethane polyethers with cyclodextrin.
22. The process of claim 21 , wherein the blend is heated to fuse the materials together to form a solid mass.
23. The process of claim 21 , wherein the cyclodextrin is selected from the group consisting of alpha (α), beta (β), and gamma (γ) cyclodextrins and mixtures thereof.
24. The process of claim 23 wherein the viscosity suppressing agent is selected from the group consisting of methylated, hydroxyethylated, hydroxypropylated, carboxymethylated, and diaminoethylated cyclodextrins and mixtures thereof.