High index and high impact resistant poly(thio)urethane/urea material, method of manufacturing same and its use in the optical field

1. A transparent, non-elastomeric, poly(thio)urethane/urea material comprising the reaction product of:

(a) at least one (α, ω)-diiso(thio)cyanate polysulfide prepolymer, said prepolymer being free from disulfide (—S—S—) linkage; and

(b) at least one aromatic primary diamine, in an equivalent molar ratio amine function/iso(thio)cyanate function (NH 2 /NCX, X═O, S) ranging from 0.5 to 2, said aromatic primary diamine being free from disulfide (—S—S—) linkage,

wherein the (α, ω)-diiso(thio)cyanate polysulfide prepolymer is the reaction product of at least one cycloaliphatic or aromatic diiso(thio)cyanate and at least one (α, ω)-diol prepolymer, and wherein the (α, ω)-diol prepolymer contains at least one sulfur atom in its chain.

2. The material of claim 1 , wherein the equivalent ratio NH 2 /NCX ranges from 0.90 to 1.10.

3. The material of claim 1 , wherein the equivalent ratio NH 2 /NCX ranges from 0.93 to 0.95.

4. The material of claim 1 , wherein said (α, ω)-diol prepolymer is a polysulfide or a mixture of polysulfides.

5. The material of claim 4 , wherein the polysulfide or mixture of polysulfides is a polysulfide of formula (Id):

HO(CH 2 ) 2 —S—(CH 2 ) 2 —[O—(CH 2 ) 3 —S—(CH 2 ) 3 —O—(CH 2 ) 2 —S—(CH 2 ) 2 ] n —OH

in which n is an integer ranging from 1 to 6.

6. The material of claim 4 , wherein the polysulfide or mixture of polysulfides is a polysulfide of formula (Ie):

HO—(CH 2 ) m+2 —S—(CH 2 ) 2 —S—(CH 2 ) 2 —[S—(CH 2 ) 3 —S—(CH 2 ) 3 —S—(CH 2 ) 2 —S—(CH 2 ) 2 ] n′ —S—(CH 2 ) m+2 —OH

wherein m is an integer ranging from 1 to 4, and n′ is an integer ranging from 1 to 6.

7. The material of claim 4 , wherein the polysulfide or mixture of polysulfides is a polysulfide of formula (If):

HO—(CH 2 ) 2 —S—(CH 2 ) 3 —[S—(CH 2 ) 3 —S—(CH 2 ) 2 —S—(CH 2 ) 2 —S—(CH 2 ) 3 ] n′ —S—(CH 2 ) 3 —S—(CH 2 ) 2 —OH

wherein n′ is an integer ranging from 1 to 6.

8. The material of claim 1 , wherein the aromatic diamine contains at least one sulfur atom in its molecule.

9. The material of claim 8 wherein the diamine is selected from:

in which R is H or an alkyl group and R′ is an alkyl group, and mixtures of the above diamines.

10. The material of claim 9 , wherein the diamine is a mixture of by weight relative to the weight of said diamine:

11. The material of claim 1 , wherein the material is the reaction product of:

a) said at least one (α, ω)-diiso(thio)cyanate polysulfide prepolymer;

b) said at least one aromatic primary diamine; and

c) at least one di-, tri-, or tetra alcohol, or at least one di-, tri-, or tetra thiol, or a mixture thereof.

12. The material of claim 11 , wherein the alcohols and thiols are selected from the group consisting of:

and mixtures thereof.

13. The material of claim 1 having a refractive index, n D 25 , higher than 1.53.

14. The material of claim 1 having a refractive index, n D 25 , of at least 1.55.

15. The material of claim 1 having a refractive index, n D 25 , of at least 1.57.

16. The material of claim 1 , wherein the at least one (α, ω)-diiso(thio)cyanate polysulfide prepolymer has a number average molecular weight of not more than 3000 g mol −1 .

17. An optical article made from a material according to claim 1 .

18. The optical article of claim 17 , wherein said article is selected from the group consisting of sun lenses, ophthalmic lenses and protective lenses.

19. A transparent, non-elastomeric, poly(thio)urethane/urea material comprising the reaction product of:

(a) at least one (α, ω)-diiso(thio)cyanate polysulfide prepolymer, said prepolymer being free from disulfide (—S—S—) linkage; and

(b) at least one aromatic primary diamine, in an equivalent molar ratio amine function/iso(thio)cyanate function (NH 2 /NCX, X═O, S) ranging from 0.5 to 2, said aromatic primary diamine being free from disulfide (—S—S—) linkage,

wherein the (α, ω)-diiso(thio)cyanate polysulfide prepolymer is the reaction product of at least one cycloaliphatic or aromatic diiso(thio)cyanate and at least one (α, ω)-diol prepolymer,

wherein the material is the reaction product of:

a) said at least one (α, ω)-diiso(thio)cyanate polysulfide prepolymer;

b) said at least one aromatic primary diamine; and

c) at least one di-, tri-, or tetra alcohol, or at least one di-, tri-, or tetra thiol, or a mixture thereof.