Non isocyanate polyurethane foams

1. A curable isocyanate free formulation for preparing a polyurethane foam comprising the following compounds:

Compound A chosen from multifunctional cyclic carbonates of formula (I) or a mixture thereof:

wherein:

i is an integer from 2 to 10,

R 1 is a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl, an heterocycle, an aryl or an heteroaryl, said hydrocarbon chain having from 3 to 60 carbon atoms,

Compound B chosen from multifunctional cyclic carbonates containing oxyalkylene groups —OR 3 — of formula (II), except polypropylene oxide bis-carbonate, or a mixture thereof:

wherein:

i′ is an integer from 2 to 10,

R 1′ is a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl, an heterocycle, an aryl or an heteroaryl, said hydrocarbon chain having from 3 to 60 carbon atoms,

j is an integer from 1 to 10,

R 3 is a linear or branched hydrocarbon chain having from 2 to 6 carbon atoms,

Compound C chosen from multifunctional amines of formula (III) or a mixture thereof:

wherein:

k is an integer from 2 to 6,

R 2 is a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl or an heterocycle, said hydrocarbon chain having from 2 to 60 carbon atoms,

Compound D chosen from non-reactive blowing agents.

2. The curable isocyanate free formulation according to claim 1 , wherein R 1 and R 1′ , identical or different, are a linear or branched hydrocarbon chain having 3 to 10 carbon atoms.

3. The curable isocyanate free formulation according to claim 1 , wherein i and i′, identical or different, are integers from 2 to 6.

4. The curable isocyanate free formulation according to claim 1 , wherein:

Compound A is chosen from a compound of formula (Ia):

Compound B is chosen from compounds of formula (IIa) or a mixture thereof:

wherein:

q represents an integer from 2 to 20 and

n, m and p, identical or different, represent integers from 1 to 20.

5. The curable isocyanate free formulation according to claim 4 , wherein:

Compound A is chosen from a compound of formula (Ia)

Compound B is chosen from a compound of formula (IIa) or a mixture thereof wherein q =2 and n, m, and p are 6 or 7.

6. The curable isocyanate free formulation according to claim 1 , wherein the Compound C is chosen from 1,2-diamonethane, 1,3-diaminopropane, butane-1,4-diamine, pentane-1,5-diamine, 1,6-diaminohexane, 1,12 diaminododecane, isophorondiamine, polyethylene imine or dimeric fatty acid diamines.

7. The curable isocyanate free formulation according to claim 1 , wherein compound D is chosen from liquids which boiling point is below 100° C., hydrocarbons, ethers, halogenated hydrocarbons, nitriles, nitrogen or carbon dioxide, or mixtures thereof.

8. The curable isocyanate free formulation according to claim 1 , further comprising a catalyst as compound E.

9. A process for preparing a flexible non-isocyanate polyurethane foam comprising the steps of:

reacting compounds A and B with compound C in the presence of compound D and a catalyst as compound E so as to form an expanded reaction mixture,

curing said expanded reaction mixture so as to form a flexible non-isocyanate polyurethane foam,

wherein compounds A, B, C, and D comprise the curable isocyanate free formulation defined in claim 1 .

10. The process according to claim 9 , wherein:

compounds A and B are first mixed with compound E and compound C, so as to form a reaction mixture and start the polymerization of said reaction mixture,

then compound D is added to this reaction mixture.

11. A foamable system comprising:

a first part A containing:

Compound A which is chosen from multifunctional cyclic carbonates of formula (I) or a mixture thereof:

wherein:

i is an integer from 2 to 10,

R 1 is a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl, an heterocycle, an aryl or an heteroaryl, said hydrocarbon chain having from 3 to 60 carbon atoms,

Compound B which is chosen from multifunctional cyclic carbonates containing oxyalkylene groups —OR 3 — of formula (II), except polypropylene oxide bis-carbonate, or a mixture thereof:

wherein:

i′ is an integer from 2 to 10,

R 1 ′ a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl, an heterocycle, an aryl or an heteroaryl, said hydrocarbon chain having from 3 to 60 carbon atoms,

j is an integer from 1 to 10,

R 3 is a linear or branched hydrocarbon chain having from 2 to 6 carbon atoms,

a second part B containing compound C chosen from multifunctional amines of formula (III) or a mixture thereof:

wherein:

k is an integer from 2 to 6,

R 2 is a linear or branched hydrocarbon chain one or several carbon atoms of which may be replaced with an heteroatom, a cycloalkyl or an heterocycle, said hydrocarbon chain having from 2 to 60 carbon atoms.

12. The foamable system according to claim 11 , further comprising a catalyst as compound E either in part A or in part B, or in a third part C preferably physically separated from part A and part B.

13. The foamable system according to claim 11 , further comprising a non-reactive blowing agent as compound D either in part A, in part B or in third part C, or in a fourth part D preferably physically separated from part A, part B and part C.

14. The curable isocyanate free formulation according to claim 8 , wherein the catalyst as compound E is chosen from amine catalysts or organometallic catalysts or mixtures thereof.

15. The foamable system of claim 11 , wherein part A and part B are physically separated.