Moisture curable silylated polymer containing free polyols for coating, adhesive and sealant application
View Patent ↗The present invention relates to moisture-curable silylated polymers having unreacted or “free” hydroxyl groups prior to cure with improved physical properties, lower viscosity and lower cost, suitable for preparing coatings, adhesives and sealants.
1. A moisture-curable composition comprising:
a) silylated polymer;
b) at least one polyol; and,
c) catalyst for the silylated polymer and polyol reaction, said composition being substantially devoid of moisture,
wherein said at least one polyol is a mixture of high molecular weight polyol and low molecular weight polyol.
2. The moisture-curable composition of claim 1 , wherein the silylated polymer is at least one member selected from the group consisting of: (i) silylated polymer obtained from the reaction of polyol with isocyanatosilane, (ii) silylated polymer obtained from the reaction of hydroxyl terminated polyurethane prepolymer with isocyanatosilane; (iii) silylated polymer obtained from the reaction of isocyanto-terminated polyurethane prepolymer with hydrogen active organofunctional silane that can react with isocyanate; and (iv) silylated polymer obtained from the reaction of unsaturated carbon-carbon terminated polyoxyalkylene polymer with a compound having a hydrogen-silicon bond to obtain silane terminated polyether.
3. The moisture-curable composition of claim 1 , wherein the low molecular weight polyol and high molecular weight polyol have at least 2 hydroxyl groups.
4. The moisture-curable composition of claim 1 , wherein the high molecular weight polyol is selected from the group consisting of aliphatic and aromatic polyester polyols, polyether polyols, polyhydroxy polycarbonates, polyhydroxy polyacetals, polyhydroxy polyacrylates, polyhydroxy polyester amides and polyhydroxy polythioethers, polyolefin polyols, and mixtures thereof.
5. The moisture-curable composition of claim 1 , wherein the low molecular weight polyol is selected from the group consisting of glycols, glycerine, trimethylol propane, pentaerythritol, glycosides, sugars, alkylol amine, and mixtures thereof.
6. The moisture-curable composition of claim 5 , wherein the polyol is selected from the group consisting of glycol, triethylene glycol, propylene glycol, butanediol, hexylene glycol, trimethylol propane, dietheylene glycol, dipropylene glycol, mannide, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylol ethane, pentaerythritol, mannitol, sorbitol, sucrose, diethanolamine, triethanolamine, and mixtures thereof.
7. The moisture-curable composition of claim 4 , wherein the high molecular weight polyol has an equivalent weight of at least 200.
8. The moisture-curable composition of claim 4 , wherein the high molecular weight polyol has an equivalent weight of about 400 to about 20,000.
9. The moisture-curable composition of claim 4 , wherein the high molecular weight polyol has an equivalent weight of about 500 to about 18,000.
10. The moisture-curable composition of claim 1 , wherein the polyol is present at a level providing from about 1 to about 100 hydroxyl mole percent, per mole of alkoxy in the silylated polymer.
11. The moisture-curable composition of claim 1 , wherein the polyol is present at a level providing from about 5 to about 80 hydroxyl mole percent, per mole of alkoxy in the silylated polymer.
12. The moisture-curable composition of claim 1 , wherein the polyol is present at a level providing from about 5 to about 50 hydroxyl mole percent, per mole of alkoxy in the silylated polymer.
13. The moisture-curable composition of claim 1 , wherein the catalyst is an organometallic catalyst.
14. The moisture-curable composition of claim 1 , wherein the catalyst is an amine catalyst.
15. The moisture-curable composition of claim 1 , wherein the catalyst is an amine catalyst is selected from the group consisting of primary amine, secondary amine, tertiary amine, aminosilane, and mixture thereof.
16. The moisture-curable composition of claim 13 , wherein the catalyst is selected from the group consisting of organic dibutyltin, zirconium complex, aluminum chelate, titanic chelate, organic zinc, organic cobalt, organic iron, organic nickel and organobismuth, and mixture thereof.
17. The moisture-curable composition of claim 1 , wherein the catalyst is a mixture of organometallic catalyst and amine catalyst.
18. A moisture-curable sealant, coating or adhesive made from the moisture-curable mixture of claim 1 .
19. The moisture-curable composition of claim 1 , optionally containing at least one of the following: additive, filler, dye, plasticizer, thickener, coupling agent, extender and UV stabilizers, and/or mixture thereof.