Mixtures of polymers for medical use

Claim 2

Polymer compositions, useful especially in the medical field, consisting of a mixture of vinyl chloride polymer and a polyether--urethane with tertiary amine and/or ammonium groups and heparin, with the porportion of the polyether--urethane being from 1 to 99% by weight, relative to the total mixture.

Claim 3

The polymer compositions according to claim 1 wherein the ammonium groups are quaternary ammonium groups.

Claim 4

Composition according to claim 1, characterised in the at the proportions of polyurethane is between 20 and 60% by weight.

Claim 5

Compositions according to claim 1 characterized in that the vinyl chloride polymer comprises at least 60% by weight of chloroethylene units.

Claim 6

Compositions according to claim 1 characterised in that the vinyl chloride polymer is a vinyl chloride homopolymer or a vinyl chloride/vinyl ester copolymer.

Claim 7

Compositions according to claim 1, characterised in that the polyether-urethanes are polyurethanes comprising oxyalkylene groups.

Claim 8

Compositions according to claim 1 characterised in that they satisfy: m+p≧0.5 and p+q≧n-2.5, the letters n, m, p and q respectively denoting: n: the number of milliequivalents of oxethylene units-- O--CH 2 --CH 2 --per 100 g of polyurethane, m: the number of milliequivalents of tertiary amine groups, which may or may not be salified, per 100 g of polyurethane, p: the number of milliequivalents of quaternary ammonium groups per 100 q of polyurethane, and q: the number of milliequivalent of ionic groups per 100 g of vinyl chloride polymer.

Claim 9

Compositions according to claim 1, characterised in that the polyether-urethanes comprise a plurality of repeat units of the formula: --A--NH--CO--O--B--O--CO--NH-- (I) and of repeat units of the formula: --A--NH--CO--Z--NH-- (II) in which formulae: B is the divalent radical in macrodiol of the polyether type, of the formula: HO--B--OH, A is the divalent radical in an aliphatic and/or cycloaliphatic and/or aromatic diisocyanate of the formula: O═C═N--A--N═C═O, and Z is a valence bond or a divalent radical such as: --NH--NH--CO--, --NH--CH 2 --CO--NH--NH--CO--, --NR 2 --D--NR 3 --CO or --O--M--O--CO--; R 2 , R 3 and M are such that NHR 2 --D--NHR 3 is a primary or secondary diamine and HO--M--OH is a diol.

Claim 10

Compositions according to claim 1 characterised in that the proportion of heparin is between 1 and 15%, relative to the polymers.

Claim 11

Compositions according to claim 7, characterised in that p 1 -q 1 >0 and in that the proportion of herparin is between 0.5 and 35% by weight relative to all the polymers, p 1 being the product of p multiplied by the percentage by weight of the polyurethane in the mixture, divided by 100, and q 1 being the product of q multiplied by the percentage by weight of the of the vinyl chloride polymer, with ionic sites, in the mixture, divided by 100.