Process of preparation of a new memory thermoplastic composition from polycaprolactone and polyurethane, product obtained by this process and its use particularly in orthopedics

Claim 2

A process for preparing a water-insoluble thermoplastic composition having elastic memory and containing polycaprolactone and polyurethane, comprising the steps of (a) forming a mixture comprising at least one polyol, at least one polyisocyanate and from 60 to 100 parts by weight unmodified polycaprolactone, the amounts of polyol and isocyanate in said mixture being such that the number of free NCO groups of the isocyanate is substantially equal to the number of free OH groups of said polyol and the total amount of polyol and polyisocyanate producing from 2 to 40 parts by weight polyurethane when reacted with each other; and (b) polymerizing said polyol and said polyisocyanate with each other in the presence of said unmodified polycaprolactone to form said polyurethane interlocked in the network of said polycaprolactone.

Claim 3

A process according to claim 1, wherein said polyisocyanate is selected from the group consisting of 2,4-toluenediisocyanate, 2,6-hexamethylenediisocyanate, 1,4-cyclohexanediisocyanate, 4,4'-dicyclohexylmethanediisocyanate, isophoronediisocyanate and mixtures thereof.

Claim 4

A process according to claim 1, wherein said polyol is selected from the group of polyetherpolyols obtained by condensation of (A) an alkylene oxide selected from the group consisting of ethylene oxide and propylene oxide with (B) (i) a diol selected from the group consisting of ethyleneglycol, propyleneglycol, diethyleneglycol, hexamethyleneglycol, tetramethyleneglycol and cyclohexyl-1,4-dimethanol, (ii) pentaerythritol, or (iii) a hexol selected from the group consisting of dulcitol and sorbitol, the condensation being carried out in the proportion of about 1 to about 20 epoxide groups per free OH groups.

Claim 5

A process according to claim 1, wherein said polyol is a polyether-polyol corresponding to the formula HO--(CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --O).sub.n --H where n is a number between 6 and 42.

Claim 6

A process according to claim 1, wherein the formation of the polyurethane is carried out in the presence of at least one substance selected from the group consisting of inorganic fillers, coloring agents and plasticizers.

Claim 7

A process according to claim 5, wherein said inorganic filler comprises at the most 35 parts by weight per 60 to 100 parts of polycaprolactone.

Claim 8

A process according to claim 5, wherein said plasticizer comprises at the most 5 parts by weight per 60 to 100 parts by weight of polycaprolactone.

Claim 9

A process according to claim 1, which comprises the steps of: mixing while stirring polycaprolactone with said polyisocyanate and said polyol at a temperature between 75° C. and 130° C. for 1 to 10 minutes to initiate formation of the polyurethane in the network of the polycaprolactone, then continuing the polymerization of the polyurethane in the network of the polycaprolactone at a temperature of at least 60° C. for 10 to 30 minutes.

Claim 10

A process according to claim 1, which comprises the steps of: mixing with stirring of the polycaprolactone with a reaction mixture resulting from prepolymerization of said polyisocyanate and said polyol at a temperature between 75° C. and 130° C. for 1 to 10 minutes to initiate the formation of the polyurethane in the network of the polycaprolactone, then continuing the polymerization of the polyurethane in the network of the polycaprolactone at a temperature of at least 60° C. for 10 to 30 minutes.

Claim 11

A process according to claim 8, further comprising the step of molding the resulting composition after said polymerization.

Claim 12

A process according to claim 8, further comprising the step of molding the resulting composition during said polymerization.

Claim 13

A process according to claim 9, further comprising the step of molding the resulting composition after said polymerization.

Claim 14

A process according to claim 9, further comprising the step of molding the resulting composition during said polymerization.

Claim 15

An orthopedic immobilizing device produced by the process of claim 10.

Claim 16

An orthopedic immobilizing device produced by the process of claim 11.

Claim 17

A process according to claim 1, wherein said polyol and said polyisocyanate are mixed together and thereafter mixed with said unmodified polycaprolactone.

Claim 18

A water-insoluble thermoplastic composition having elastic memory and containing polycaprolactone and polyurethane, said composition being the product of a process comprising the steps of (a) forming a mixture comprising at least one polyol, at least one polyisocyanate and from 60 to 100 parts by weight unmodified polycaprolactone, the amounts of polyol and isocyanate in said mixture being such that the number of free NCO groups of the isocyanate is substantially equal to the number of free OH groups of said polyol and the total amount of polyol and polyisocyanate producing from 20 to 40 parts by weight polyurethane when reacted with each other; and (b) polymerizing said polyol and said polyisocyanate with each other in the presence of said unmodified polycaprolactone to form said polyurethane interlocked in the network of said polycaprolactone.

Claim 19

A water-insoluble thermoplastic composition having elastic memory and containing polycaprolactone and polyurethane, said composition being the product of a process comprising the steps of (a) forming a mixture comprising at least one polyol, at least one polyisocyanate and from 60 to 100 parts by weight unmodified polycaprolactone, the amounts of polyol and isocyanate in said mixture being such that the number of free NCO groups of the isocyanate is substantially equal to the number of free OH groups of said polyol and the total amount of polyol and polyisocyanate producing from 20 to 40 parts by weight polyurethane when reacted with each other; and (b) polymerizing said polyol and said polyisocyanate with each other in the presence of said unmodified polycaprolactone to form said polyurethane interlocked in the network of said polycaprolactone.

Claim 20

A thermoplastic composition according to claim 17, wherein said polyol and said polyisocyanate are mixed together and thereafter added to said unmodified polycaprolactone.

Claim 21

A thermoplastic composition according to claim 17, which comprises (A) 60 to 95 parts by weight of unmodified polycaprolactone, and (B) 5 to 40 parts by weight of polyurethane.