Silicone-polyether block copolymers having a defined polydispersity in the polyoxyalkylene part and their use as stabilizers for producing polyurethane foams

1. A silicone-polyether copolymer:

prepared by organomodification of branched polysiloxanes having terminal and/or lateral SiH functions or linear polysiloxanes having lateral and/or terminal SiH functions by means of polyethers or polyether mixtures;

wherein the polyethers used have a polydispersity M w /M n in the range from 1.0 to 1.5 and ratios M n /WM IN and M w /MW IN in the range from 0.7 to 1.3.

2. The silicone-polyether copolymers according to claim 1 ;

wherein the polysiloxane after organomodification is a silicone-polyether copolymer of the formula (I);

where:

n and n 1 are each, independently of one another, from 0 to 500 and (n+n 1 ) is <500,

m and m 1 are each, independently of one another, from 0 to 60 and (m+m 1 ) is <60,

k is from 0 to 50,

R is at least one radical from the group consisting of linear, cyclic or branched, aliphatic or aromatic, saturated or unsaturated hydrocarbon radicals having from 1 to 20 carbon atoms,

R 1 is R or R 3 ,

R 2 is R or a heteroatom-substituted, functional, organic, saturated or unsaturated radical,

R 3 is selected from:

R;

CH 2 —CH 2 —CH 2 —O—(CH 2 —CH 2 O—) x —(CH 2 —C H (R′)O—) y —(SO) z —R″;

CH 2 —CH 2 —O—(CH 2 —CH 2 O—) x —(CH 2 —CH(R′)O—) y —R″;

CH 2 —R IV ;

CH 2 CH 2 —(O) x′ —R IV ;

CH 2 —CH 2 —CH 2 —O—CH 2 —CH(OH)—CH 2 OH;

and

CH 2 —CH 2 —CH 2 —O—CH 2 —C(CH 2 OH) 2 —CH 2 —CH 3 ;

where:

x=0 to 100,

x′=0 or 1,

y=0 to 100,

z=0 to 100,

R′ is an alkyl or aryl group which has from 1 to 12 carbon atoms and is unsubstituted or substituted;

R″ is a hydrogen radical or an alkyl group having from 1 to 4 carbon atoms, a —C(O)—R′″ group where R′″ alkyl radical, a —CH, —O—R′ group, an alkylaryl group, or the —C(O)NH—R′ group;

R IV is a hydrocarbon radical which has from 1 to 50 carbon atoms and is unsubstituted or substituted;

SO is a styrene oxide radical —CH(C 6 H 5 )—CH 2 —O—;

with the proviso that

at least one substituent from among R 1 , R 2 , and R 3 is not R; and

at least one substituent from among R 1 , R 2 , and R 3 is a polyether which has a polydispersity M w /M n in the range from 1.0 to 1.5 and ratios M n /MW IN and M w /MW IN in the range from 0.7 to 1.3.

3. The silicone-polyether copolymers or mixtures thereof according to claim 2 having the formula (I);

wherein:

k is >0; and

R 1 is different from R.

4. The silicone-polyether copolymers according to claim 2 ;

wherein:

R is a methyl group;

R 2 is R or a radical selected from the group consisting of alkyl, chloroalkyl, chloroaryl, fluoroalkyl, cyanoalkyl, acryloxyaryl, acryloxyalkyl, methacryloxyalkyl, methacryloxypropyl, and vinyl radicals;

R′ is an alkyl or aryl group which has from 1 to 12 carbon atoms and is unsubstituted or substituted, alkyl radicals, aryl radicals; or haloalkyl or haloaryl radicals;

R″ is a hydrogen radical or an alkyl group having from 1 to 4 carbon atoms, a —C(O)—R′″ group where R′″=alkyl radical, a —CH 2 O—R′ group, an alkylaryl group, a benzyl group, or the —C(O)NH—R′ group; and

R IV is a hydrocarbon radical which has from 1 to 50 carbon atoms and is unsubstituted or substituted by halogens;

with the proviso that:

at least one substituent from among R 1 , R 2 ; and R 3 is not R; and

at least one substituent from among R 1 , R 2 , and R 3 is a polyether which has a polydispersity M w /M n in the range from 1.0 to 1.5 and ratios M n /MW IN and M w /MW IN in the range from 0.7 to 1.3.

5. The silicone-polyether copolymers according to claim 2 ;

wherein:

all radicals R are methyl radicals;

R 2 is R or a radical selected from the group consisting of methyl, chloropropyl, vinyl, and methacryloxypropyl radicals;

R′ is an alkyl or aryl group which has from 1 to 12 carbon atoms and are alkyl radicals, aryl radicals, or haloalkyl or haloaryl radicals;

R″ is a hydrogen radical or an alkyl group having from 1 to 4 carbon atoms, a —C(O)—R′″ group where R′″=alkyl radical, a —CH 2 —O—R′ group, a benzyl group, or the —C(O)NH—R′ group; and

R IV is a hydrocarbon radical which has from 1 to 50 carbon atoms and is unsubstituted or substituted, by halogens

with the proviso that

at least one substituent from among R 1 , R 2 , R 3 is not R; and

least one substituent from among R 1 , R 2 , and R 3 is a polyether which has a polydispersity M w /M n in the range from 1.0 to 1.5 and ratios M n /MW IN and M w MW IN in the range from 0.7 to 1.3.

6. The silicone-polyether copolymers according to claim 2 :

wherein:

each radical R is a methyl radical;

R 2 is R or a heteroatom-substituted, functional, organic, saturated or unsaturated radical, selected from the group consisting of alkyl, chloroalkyl, chloroaryl, fluoroalkyl, cyanoalkyl, acryloxyaryl, acryloxyalkyl, methacryloxyalkyl, methacryloxypropyl, vinyl radicals, methyl, chloropropyl, vinyl, and methacryloxypropyl radicals.

7. A composition comprising:

one or more silicone-polyether copolymers according to claim 1 optionally with further additives.

8. A composition comprising:

one or more silicone-polyether copolymers according to claim 1 as polyurethane foam stabilizer(s); and

further additives selected from the group consisting of nucleating agents, cell-refining additives, cell openers, crosslinkers, emulsifiers, amine catalysts, metal catalysts, buffer substances, flame retardants, antioxidants, antistatics, biocides, colour pastes, and solid fillers for stabilizing polyurethane foams.

9. A composition containing:

silicone-polyether copolymers according to claim 8 ; and

solvents selected from the group consisting of glycols, alkoxylates, carbonates, ethers, esters, branched and linear aliphatic and aromatic hydrocarbons, and oils of synthetic and/or natural origin.

10. A method of stabilizing a polyurethane foam which comprises:

adding a silicone-polyether copolymer of claim 1 to a polyurethane foam.

11. A method for foaming a polyurethane foam comprising:

combining a silicone-polyether copolymer according to claim 1 with a blowing agent selected from the group consisting of water, methylene chloride, pentane, alkanes, halogenated alkanes, acetone, and carbon dioxide.

12. A polyurethane foam stabilized using a silicone-polyether copolymer according to claim 1 .

13. A polymer article consisting of:

a polyurethane foam according to claim 12 .