Reactive amine-functional silicone-polyether block copolymers

1. A silicone-polyether block copolymer having the average formula:

R 4 R 1 2 Si(OR 5 2 Si) m {[R 2 O(C q H 2q O) p R 2 R 1 2 Si(OR 5 2 Si) k ] n R 2 O(C q H 2q O) p R 2 R 1 2 Si(OR 5 2 Si) m } h OSiR 1 2 R 4 ,

wherein R 1 is C 1 -C 10 hydrocarbyl; R 2 is C 1 -C 10 hydrocarbylene; R 3 is R 1 or H; R 4 is —R 2 —NR 3 2 or —R 2 —NR 3 —R 2 —NR 3 2 ; R 5 is R 1 or R 4 ; h is from 1 to 100; k is from 2 to 500; m is from 2 to 500; n is from 0 to 30; p is from 2 to 120; and q is from 2 to 4; wherein the copolymer contains per molecule an average of at least one R 5 group for which R 5 is —R 2 —NR 3 2 or —R 2 —NR 3 —R 2 —NR 3 2 .

2. The silicone-polyether block copolymer of claim 1 , wherein the at least one R 5 group is a pendent amine selected from the group consisting of N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, N-ethylaminoisobutyl, 3-aminopropyl, and N-(2-aminoethyl)-3-aminoisobutyl.

3. The silicone-polyether block copolymer of claim 2 , wherein the at least one R 5 group is N-(2-aminoethyl)-3-aminoisobutyl.

4. The silicone-polyether block copolymer of claim 3 , wherein each terminal R 4 group is N-methyl-3-aminoisobutyl.

5. The silicone-polyether block copolymer of claim 1 , wherein h is from 1 to 10.

6. The silicone-polyether block copolymer of claim 1 , wherein each R 1 group is independently selected from the group consisting of methyl, ethyl, and phenyl.

7. A method of preparing a silicone-polyether block copolymer, the method comprising:

combining

(a) a polyether having the formula

ZR 1 2 Si(OR 1 2 Si) m [R 2 O(C q H 2q O) p R 2 R 1 2 Si(OR 1 2 Si) k ] n R 2 O(C q H 2q O) p R 2 R 1 2 Si(OR 1 2 Si) m Z;

(b) an organosilicon component selected from the group consisting of

(i) at least one cyclosiloxane having the formula (R 5 2 SiO) t ,

(ii) at least one linear siloxane having the formula Z(R 5 2 SiO) v SiR 5 2 Z,

(iii) at least one silane having the formula R 5 2 Si(OR 3 ) 2 ,

(iv) an organosilicon mixture comprising at least two organosilicon components selected from (b)(i), (b)(ii), and (b)(iii), and

(v) an organosilicon mixture comprising water and at least one organosilicon component selected from (b)(i), (b)(ii), and (b)(iii);

(c) an endblocking agent selected from

(i) at least one sila-aza-cyclopentane having the formula

(ii) at least one silane having the formula R 4 R 5 2 Si(OR 3 ),

(iii) at least one siloxane having the formula R 4 R 5 2 SiO(R 5 2 SiO) w SiR 5 3 , and

(iv) an endblocker mixture comprising at least two endblocking agents selected from (c)(i), (c)(ii), and (c)(iii); and

(d) at least one catalyst

to form a reaction mixture, wherein R 1 is C 1 -C 10 hydrocarbyl; R 2 is C 1 -C 10 hydrocarbylene; R 3 is R 1 or H; R 4 is —R 2 —NR 3 2 or —R 2 —NR 3 —R 2 —NR 3 2 ; R 5 is R 1 or R 4 ; R 6 is —CH 3 or H; Z is hydroxyl or a hydrolysable group; m is from 2 to 500; n is from 0 to 30; p is from 2 to 50; q is from 2 to 4; t is from 3 to 8; v is from 1 to 50; w is from 0 to 200; the mole ratio of the organosilicon component (b) to the polyether (a) is from 1.01 to 2; and the mole ratio of the endblocking agent (c) to the polyether (a) is from 0.02 to 2; and

heating the reaction mixture at a temperature from 50° C. to 200° C. for a sufficient amount of time to produce a silicone-polyether copolymer having a number-average molecular weight from 2000 to 500,000, provided the silicone-polyether copolymer contains per molecule an average of at least one R 5 group for which R 5 is R 4 .

8. The method of claim 7 , wherein the organosilicon component is an organosilicon mixture comprising water and at least one first cyclosiloxane having the formula (R 7 2 SiO) t , wherein each R 7 is independently methyl or phenyl and t is 4 or 5.

9. The method of claim 8 , wherein for the at least one first cyclosiloxane each R 7 is methyl and t is 5.

10. The method of claim 7 , wherein the organosilicon component is selected from the group consisting of:

at least one silane having the formula R 8 2 Si(OR 3 ) 2 , wherein R 8 is R 5 and at least one group R 8 is selected from the group consisting of N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, N-ethylaminoisobutyl, 3-aminopropyl, and N-(2-aminoethyl)-3-aminoisobutyl; and

an organosilicon mixture comprising at least one of the preceding silanes.

11. The method of claim 10 , wherein at least one group R 8 is N-(2-aminoethyl)-3-aminoisobutyl and each R 3 is independently methyl or ethyl.

12. The method of claim 7 , wherein the organosilicon component is an organosilicon mixture comprising:

at least one cyclosiloxane having the formula (R 7 2 SiO) t , wherein each R 7 is independently methyl or phenyl and t is 4 or 5;

water; and

at least one silane having the formula R 8 2 Si(OR 3 ) 2 , wherein R 8 is R 5 and at least one group R 8 is selected from the group consisting of N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, N-ethylaminoisobutyl, 3-aminopropyl, and N-(2-aminoethyl)-3-aminoisobutyl.

13. The method of claim 7 , wherein the endblocking agent is selected from:

N-methyl-aza-2,2,4-trimethylsilacyclopentane;

N-aminoethyl-aza-2,2,4-trimethylsilacyclopentane;

3-aminopropyldimethylethoxysilane;

3-aminopropyldiisopropylethoxysilane;

1-amino-2-(dimethylethoxysilyl)propane;

aminoethylaminopropyldimethylethoxysilane;

1,2-bis(3-aminopropyl)-tetramethyldisiloxane;

3-aminopropylpentamethyldisiloxane;

1,2-bis(2-aminoethylaminomethyl)-tetramethyldisiloxane; and

an endblocker mixture comprising at least two of the preceding compounds.

14. The method of claim 13 , wherein the organosilicon component is an organosilicon mixture comprising:

at least one cyclosiloxane having the formula (R 7 2 SiO) t , wherein each R 7 is independently methyl or phenyl and t is 4 or 5;

water; and

at least one silane having the formula R 8 2 Si(OR 3 ) 2 , wherein R 8 is R 5 and at least one group R 8 is selected from the group consisting of N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, N-ethylaminoisobutyl, 3-aminopropyl, and N-(2-aminoethyl)-3-aminoisobutyl.

15. The method of claim 14 , wherein the endblocking agent is

a sila-aza-cyclopentane selected from N-methyl-aza-2,2,4-trimethylsilacyclopentane or N-aminoethyl-aza-2,2,4-trimethylsilacyclopentane; or

an endblocker mixture comprising at least one of the preceding sila-aza-cyclopentanes.

16. The method of claim 7 , wherein the catalyst is selected from the group consisting of alkali metal hydroxides, ammonium hydroxides, quaternary ammonium salts, and mixtures thereof.

17. The method of claim 7 , wherein the catalyst comprises at least one metalorganic complex of a metal selected from the group consisting of platinum, titanium, tin, yttrium, nickel, copper, calcium, and combinations thereof.

18. A silicone-polyether block copolymer prepared by the method according to claim 7 .