GB1605079A

GB1605079A - Polyurethane polymers

Info

Publication number: GB1605079A
Application number: GB2468478A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-06-23
Filing date: 1978-05-31
Publication date: 1981-12-16
Also published as: JPH0314848B2; CA1155591A; JPH01131229A; FR2440380A1; FR2440380B1; JPS6237651B2; DE2827450A1; JPS5410398A

Description

(54) POLYURETHANE POLYMERS (71) I, FRANCIS EUGENE GOULD, a citizen of the United States of America, of 29 Cedar Lane, Princeton, New Jersey, 08540, United States of America, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to hydrophilic polyurethane polymers. These polymers generally have a molecular weight above 6,000. They have lactone groups and preferably free hydroxyl groups in the polymer backbone. They can be prepared by reacting a mixture of polyols, a polyfunctional lactone and a polyfunctional isocyanate proportioned so as to provide the desired polymer properties.

The prducts are soluble in alkaline solutions and may be used for light sensitive photographic layers on films, paper or glass; in drug delivery systems, as burn dressings, in body implants such as vascular prostheses, in molding cbmpositions, and in the manufacture of catheters. The novel polymers also find use in the manufacture of artificial finger nails, finger stalls, adhesives, and in protective and hydrostatic drag resistant coatings. The water absorptivity of the oolyurethane lactone polymers is generally above 10%, preferably in the range 20% to 60%, and these polymers may range in their physical properties from rigid solids to completely gel-like highly water-absorptive polymers. The polymers of the present invention can provide a leachable substrate wherein the leaching agent may be water, gases, alcohols, esters and body fluids, e.g., animal or human.

The polymers of the invention are lactone-modified hydrophilic polyurethane resins that are insoluble in water, but which swell in water and other solvents. More particularly, the present invention relates to polyether urethane resins having active and available lactone groups in the polymer backbone that readily open and dissolve in alkaline solutions to produce carboxylates which can be converted to free carbonyl groups. Typically they are low-melting solids, generally having flow points in the range of 90"C to 2500C which can be fabricated by typical polymer procedures.

Numerous polymer systems that contain free carboxylic acid groups are known in the art. It is difficult, however, to prepare a polyurethane that has free carboxylic acid groups for the reason that the iscyanate that is a necessary component in any polyurethane system is quite reactive with carboxylic acid groups.

One approach to the introduction of carboxylic acid groups into a polyurethane resin chain is described in U.S. Patent No. 3,412,054. In accordance with that method, a 2,2-di(hydroxymethyl) alkanoic acid such as 2,2-di(hydroxymethyl) propionic acid is reacted with an organic diisocyanate to produce a polyurethane containing unreacted carboxylic acid groups.

According to one embodiment, the present invention provides a hydrophilic polyurethane polyether resin having lactone groups in the polymer backbone.

Another embodiment of the invention provides a hydrophilic polyurethane having lactone groups in the polymer backbone and comprising the reaction product of: (A) one or more diols selected from (a) diethylene glycol, dipropylene glycol or a dihydric phenol, (b) long chain polyoxyalkylene diols having a molecuuar weight of at least 200, (c) linear polyester diols derived from the condensation of one or more diols with one or more dibasic acids, and (d) the reaction product of one or more alkylene diols or polyoxyalkylene diols with a difunctional polyester derived from the condensation of one or more diols with one or more dibasic acids; (B) a polyfunctional lactone having the formula

wherein R1 is -H, -CH2NH2, -SO,CH,, -CHOHCOOH, or -(CH0H)CH,OH; n is 0 or an integer from 1 to 5; and R2 is a divalent radical (CH0H)-; m being an integer from 2 to 10; and ethers derived from said lactones; and (C) a urethane precursor selected from organic polyisocyanates and nitrile car bonates. Preferably this polymer has a flow point below 2750 C.

Further embodiments of the invention provides: (1) an oral delivery system comprising a pharmacologically active agent and the above-defined polyurethane polymer as a carrier vehicle therefore; (2) a solution effective in the repair of skin abrasions comprising the abovedefined polyurethane polymer dissolved in a volatile non-toxic organic solvent; (3) A depilatory liquid comprising a solution in a non-toxic solvent of a depilatory agent and the above-defined polyurethane polymer; (4) a deodorant composition comprising a solution of a disinfectant, a perfume and the above-defined polyurethane polymer; (5) a method of imparting moisture to a dry gas which comprises passing the gas through a tube formed of the above-defined polyurethane polymer; (6) a hydrophilic polyurethane polyether resin characterized by a molecular weight above 6000 and having lactone groups in the polymer backbone, said urethane polymer comprising the reaction product of: (a) a polyfunctional lactone having the formula

wherein R, is a monovalent radical selected from -H, -CH2NH2, -SO2CH1, -CHOHCOOH, and -(CHOH)CH2OH; n being 0 or an interer from 1 to 5; and R2 is a divalent radical (CHOH) - n being an integer from 4 to 10; and ethers derived from said lactones (e.g. delta gluconolactone, mannolactone, sorbolactone, or D-glucuronolactone); (b) a polyalkylene oxide glycol, (e.g. polyethylene glycol having a molecular weight of 1450, or a mixture of polyethylene glycol and diethylene glycol); and (c) an organic polyisocyanate; said urethane polymer being soluble in alkaline solutions.

The long-chain, water-soluble diols should have a molecular weight of at least 200 and preferably 1450 to 60cm, although it may be even higher. These diols may be derived from ethers, esters and ether-ester block-containing resins. Suitable diols consist predominantly of oxyethylene or oxypropylene groups, through a minor proportion of other oxyalkylene groups may be included. Block copolymer polyols obtained by adding ethylene oxide to a polyoxypropylene chain are also useful as are the linear polyester diols derived from the condensation of one or more diols with one or more dibasic acids, and the reaction product of one cr more alkylene diols with a difunctional linear polyester derived from the condensation of one or more diols with one or more dibasic acids.

Representative examples of the polyfunctional lactones are those derived from polysaccharides and monosaccharides such as mannolactone, delta gluconolactone, sorbolactone and D-glucuronolactone.

It is desirable that the lactones employed have at least 9 and preferably 4 or more hydroxyl groups in the molecule or at least 1 more than is required to form a linear polyurethane chain. These free (untreated) hydroxyl groups remain in the polymer backbone and are available for cross-linking the polymer. The lactone ring is also reactive and may be opened, i.e., by hydrolysis, to form free carboxylate groups or free carboxyl groups in the polymerbackbone. The polymers formed by hydrolysis are the subject of British Patent Application No. 8033807 (eSrial No. 1605080), divided from the present application.

The number of carboxylic groups that are present in the polymer chain will be determined by the amount of lactone that is present in the reaction mixture which may be varied from 0.1% to 30% of the weight of the total reaction mixture. Preferably the weight of the lactone will be .5% to 15% of the weight of the total reaction mixture.

The polyisocyanate used in the present invention may be represented by R(NCO) wherein n is grater than 1, preferably 2-4, and R is an aliphatic, alicyclic, aliphatic-alicyclic, aromatic, or aliphatic-aromatic hydrocarbon compound of from 4 to 26 carbon atoms, but more conventionally from 6 to 20 and generally from 6 to 13 carbon atoms. Representative examples of the above isocyanates are: tetramethylene diisocyanate; hexamethylene diisocyanate; trimethylhexamethylene diisocyanate; dimer acid diisocyanate; isophorone diisocyanate; diethylbenzene diisocyanate; decamethylene 1,10-diisocyanate; cyclohexylene 1,2-diisocyanate and cyclohexylene 1,4-diisocyanate; and the aromatic isocyanates such as 2,4- and 2,6-tolylene diisocyanate; 4,4-diphenylmethane diisocyanate; 1,5-naphthalene diisocyanate; dianisidine diisocyanate; tolidine diisocyanate; a polymeric polyisocyanate such as neopentyl tetra isocyanate; 2-xylylene diisocyanate; tetrahydronaphthalene-1,5 diisocyanate; and bis (4-isocyanatophenyl) methane.

The preferred isocyanate is methylene di(cyclohexyl isocyanate). Other but slightly less preferred diisocyanate are trimethyl hexamethylene diisocyanate and isophorone diisocyanate.

Other compounds which are useful are the isocyanate equivalents which produce the urethane linkages such as the nitrile carbonates, e.g., the adiponitrile carbonate of the formula:

In the manufacture of the polyurethane resins of the present invention, component (A) (a) can be diethylene glycol and dipropylene glycol or a dihydric phenol. The preferred dihydric phenols are bisphenol A and 4,4'-sulfonyldiphenol.

The proportions in which the long chain polyglycol [i.e. components (AXb), (AXc) or (AXd)j and the low molecular weight glycol, [i.e.. component (AXa)] are used depends on the hydrophobic-hydrophilic balance present in each and desired in the final product Increasing the molecular weight of the long chain polyoxyalkylene glycol and/or the amount of this component contributes strong hydrophilic properties to the final product. This effect may be counter-balanced by increasing the proportion of low molecular weight glycol, i.e., diethylene glycol or dipropylene glycol.

Keeping the above in mind (that it is the number of polyalkylene oxide groups in the polymer molecule that determines hydrophilic properties and the polyethylene oxide groups are more hydrophilic than are polypropylene oxide groups) it is a simple matter to choose mixtures of reactants such that the final product will have the desired properties. By choosing the molecular weight of the polyalkylene glycol or using two polyalkylene glycols of different molecular weight one may "tailor make" products that satisfy a wide range of properties. Amphoteric hydrophilic polyurethane polymers may be made by adding a dialkanol tertiary amine such as diethanol methyl amine to the reaction mixture.

In making the polyurethane resins of this invention the glycols are mixed with the lactone and the polyisocyanate is reacted with the mixture, although other techniques may be used. The reaction is catalyzed by known catalyst for such reaction, suitable ones being tin salts and organic tin esters such as dibutyl tin dilaurate, tertiary amines such as triethylene diamine, N,N,N',N'-tetramethyl-1,3-butane diamine and other recognized catalysts for urethane reactions which are well known in the art. The reaction can be conducted in the absence or present of diluent or solvent.

The polyurethane polyether resins of the present invention because of their unique physical properties may advantageously be used as burn dressings. The resin may be applied to the burn as a powder, film, or from solution in a volatile non-toxic solvent and will form a barrier that is permeable to liquids. Thus the physician has a choice of medicaments which may be applied to the burn prior to the resin coating or may be added to the resin for timed release.

The above described polyurethane polyether resins are also useful as coatings, molding compounds, absorbents, controlled release agents, ion exchange resins, in the repair of skin abrasions and in the manufacture of dialysis membranes, dentures, cannulae, contact lenses, solubilizing packaging components, hair sprays, cosmetics, burn dressings, contraceptive devices, sutures, surgical implants, blood oxygenators, intrauterine devices, vascular prostheses, oral delivery systems, battery separator plates, eye bandages, depilatory compositions, corneal prostheses, perfumes, deodorant compositions, antifog coatings, surgical drapes, oxygen exchange membranes, artificial finger nails, finger stalls, adhesives, gas permeable membranes, and in protective and drag resistant coatings.

The practice of the invention is further illustrated by the following examples without being restricted thereto, the parts being by weight, unless otherwise stated.

EXAMPLE 1 A diethylene glycol solution of polyethylene glycol is prepared by heating 109.2 parts (0.075 mole) of polyethylene glycol having a molecular weight of 1450 in 17.4 parts (0.164 mole) of diethylene glycol with stirring. The solution is cooled to below 600 C. and to it is added a solution of delta gluconolactone prepared by dissolving 11.6 parts (0.065 mole) of delta gluconolactone in 46.4 parts of dimethyl sulfoxide.

Eighty and eight tenths parts (0.316 mole) of methylene bis cyclohexyl-4,4'-isocyanate (a product identified as HYLENE W sold by E. L. DuPont de Nemours & Co., Wilmington, Delawaff--"HYLENE" is a Registered Trade Mark) is added to the mixture with stirring. One half part by weight of an organic tin catalyst solution; dibutyl tin dilaurate (a product identified as T1, manufactured by Metal and Thermite Company of Rahway, New Jersey) is added to the reaction mixture with stirring at a temperature below 45" C. to avoid undue temperature rise caused by the heat of reaction. After stirring for 20 minutes, the temperature increases to 800 C. The reaction mixture is then transferred to a tray and placed in an oven at 90" C. for 1 hour to complete the reaction. This polymer, in the wet state, is soft, compliant and exible.

EXAMPLE 2.

A polymer that is insoluble in water but soluble in a mixture of a major portion of alcohol and a minor portion of aqueous base (1.0 N sodium hydroxide) is prepared by the method described in Example 1 from: Polyethylene Glycol (M. Wt. 1450) 3469 parts (2.38 mole) Diethylene glycol 254 parts (2.39 mole) Dleta Glconolactone (as a 20% solution in dimethyl sulfoxlde) 116 parts (0.65 mole) HYLENE W 808 parts (3.16 mole) Dibutyl tin dilaurate 5 parts A piece of this polymer, cast in the form of a cylinder having a volume of 10 ml. is weighed, immersed in water at room temperature for 12 hours, dried with a paper towel to remove surface moisture and again weighed. The increase in weight was 100%.

EXAMPLE 3.

A polymer containing lactone groups that is soluble in a major portion of alcohol having a minor amount of base dissolved therein, or added with a minor amount of water or other carrier is prepared by the method described above in Example 1 from: Polyethylene Glycol (M. Wt. 1450) 2000 parts (1.37 mole) Diethylene Glycol 107.5 parts (1.64 mole) Delta Gluconolactone (as a 20% solution in dimethyl sulfoxide) 116 parts (0.65 mole) HYLENE W 808 parts (3.16 mole) Stannous Octoate (T9)* 5 parts *T9 is a trademark of the Metal and Thermite Company of Rahway, New Jersey.

EXAMPLE 4.

This example illustrates the preparation of a polymer soluble in aLkaline solution using a 5% excess of cyanate groups. The method of preparation is described in Example 1.

Polyethylene Glycol (mol. wt. 1450) 1097 parts (0.75 mole) Diethylene Glycol 174 parts (1.64 mole) Delta Gluconolactone (as a 20% solution in dimethyl sulfoxide) 116 parts (0.65 mole) HYLENE W 102.4 parts (0.4 mole) Stannous Octoate (T,)* 5 parts EXAMPLE 5.

A polyurethane polyether resin is prepared by the method described in Example 1 above substituting for the polyethylene glycol a block copolymer having a molecular weight of 4750 obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of 950.

Block copolymer (M. Wt. 4750) 3577 parts Diethylene glycol 174 parts Delta gluconolactone (as a 20% solution in dimethyl sulfoxide) 116 parts HYLENE W 808 parts Dibutyl tin dilaurate 5 parts EXAMPLE 6.

A polyurethane polyether resin is prepared by the method described in Example 1 above substituting for the polyethylene glycol a block copolymer having a molecular weight of 7500 obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of 2250.

Block copolymer (M. Wt 7500) 1157.4 parts Diethylene Glycol 32.75 parts Delta gluconolactone (as a 20% solution in dimethyl sulfoxide) 116 parts HYLENE (W 808 parts Dibutyl tin dilaurate 5 parts EXAMPLE 7.

A polyurethane polyether resin is prepared by the method described in Example 1 above substituting for the polyethylene glycol a block copolymer having a molecular weight of 6500 obtained by adding poly(oxyethylene) groups to a poly(oypropylene) chain having a molecular weight of 3250.

Block copolymer 325 parts Diethylene glycol 21.76 parts Delta gluconolactone (as a 20% solution in dimethyl sulfoxide) 41.41 parts HYLENE W 132 parts Dibutyl tin dilaurate 0.5 parts EXAMPLE 8.

A polyurethane polyether resin is prepared by the method described in Example 1 above substituting for the polyethylene glycol a block copolymer having a molecular weight of 13,333 obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of about 4000.

Block copolymer 1104 parts Diethylene glycol 17.4 parts Delta gluconolactone* 11.6 parts Dimethyl sulfoxide 46.4 parts HYLENE W 80.8 parts Dibutyl tin dilaurate 3 parts * dissolved in dimethyl sulfoxide After stirring for one hour, the reaction mixture is transferred to a tray and placed in an oven at 900 C. ovemight.

EXAMPLE 9.

A series of three polyurethane polyether resins is prepared by the procedure of Example 1 in which the amount of Delta-glucano-lactone is varied.

Polyethylene glycol Diethylene Delta HYLENE Dibutyl tin (M. Wt. 1450) glycol gluconolactone* W dilaurate Resin (a) 54.6 g 8.7 g 2.9 g 40.4 g 0.5 g Resin (b) 54.6 g 8.7 g 5v8 g 40.4 g 0 5 g Resin (c) 54.6 g 8.7 g 11.6 g 48.5 g 0.5 g * dissolved in dimethyl sulfoxide After the initial reaction, instead of curing the resin in an oven the three resin (3 g. of each) were mixed with 100 mg of norethandrolone, cast in the form of cylinders 1.3 cm by 2.5 cm and polymerized at 800 C. for 30 hours. After removing from the mold, cylinders suitable for in vivo implantation to provide prolonged release of the norethant'rolone (Nilevar) are obtained for use in animal husbandry.

EXAMPLE 10.

Delta gluconolactone (14.28 parts) is ground to a fine powder and thoroughly mixed with 29.15 parts of polyethylene glycol (M. Wt. 200). The mixture is heated to 60 C. and to it is added 56.57 parts of HYLENE W and 0.5 parts of stannous octoate with stirring. After the exothermic reaction subsides, the resin is transferred into a tray and placed in an oven at 900 C. for one hour to complete the reaction.

EXAMPLE 11.

A diethylene glycol solution of polyethylene glycol is prepared by heating and stirring 249.3 parts (0.172 mole) of polyethylene glycol having a molecular weight of 1450 with 79.5 parts (0.883 mole) of diethylene glycol. To this melt is added 52.9 parts (0.296 mole) of delta gluconolactone, 249.3 parts (0.86 mole) of diethylene glycol adipate and 520 parts (1.85 moles) of methylene bis cyclohexyl-4,4'-isocyanate.

The mixture is stirred with heating to form a homogeneous melt and then cooled to 450 C. Two and one tenth parts of a solution of dibutyl tin dilaurate is added to the reaction mixture with rapid stirring to avoid undue temperature rise caused by the heat of reaction. After stirring for twenty minutes,, the temperature is 850 C. The reaction mixture is then transferred to a tray and placed in an oven at 90" C. for one hour to complete the reaction. The resulting polymer contains 21 weight percent adipic acid ester, is harder and more rigid than the polymer of Example 1 and is insoluble in water and aqueous alkaline solutions. When immersed in water the increase in weight, due to the water take up, is less than 20 percent.

EXAMPLE 12.

A polyurethane polymer derived from a linear polyester diol is prepared by reacting: polyethylene glycol (0.005 mole) 7.95 parts delta glucanolactone (0.29 mole) 5.2 parts diethylene glycol adipate (0.172 mole) 49.86 parts HYLENE W (0.241 mole) 68.0 parts The mixture of reactants is heated with stirring until homogeneous and 0.24 parts of an organic tin catalyst solution; dibutyl tin dilaurate (a product identified as T12 manufactured by Metal and Thermite Company of Rahway, New Jersey) is added to the reaction with stirring at a temperature below 45" C. to avoid undue temperature rise caused by the heat of reaction. After stirring for 20 minutes, the temperature increases to 800 C. The reaction mixture is then transferred to a tray and placed in an oven at 900 C. for 1 hour to complete the reaction. The resulting polymer contains 38 weight percent adipic acid ester and is harder and more rigid than the polymer of Example 11. It is insoluble in basic aqueous solutions and methanol. The water take up of this polymer is less than 15 weight percent EXAMPLE 13.

Example 12 above is repeated, but the amount of the diethylene glycol adipate present in the reaction mixture is reduced from 49.86 parts to 1.15 parts (1.4 weight percent of the reaction mixture). One gram of. the polymer of this example when immersed in water swells and absorbs 0.48 g water. One gram of this polymer may be dissolved in a mixture of 9 ml methanol and 1 ml of 2 N aqueous sodium hydroxide.

EXAMPLE 14.

To 90 parts by volume of a mixture of ethanol and water (70:30) is added 10 parts of the polymer of Example 1 and 1 part of sulfadiazine. The polymer is dissolved by stirring with the addition of 1 N sodium hydroxide to adjust the pH of the solution to 7.0. The polymer solution may be applied as a burn dressing directly to a burn area and upon evaporation of the solvent forms a protective skin that does not interfere with healing because of its permeability to gases and fluids but prevents the growth of -anerobic organisms under the dressing.

EXAMPLE 15.

A polymer having the composition set forth in Example 2 above is prepared by heating and stirring the polyethylene glycol, diethylene glycol, delta glucanolactone and HYLENE W to form a homogeneous mixture. The catalyst is added to the reaction mixture at 400 C. and stirring is continued until the exothermic reaction subsides (temperature starts to drop) at which time 232 parts (5 weight percent) of cortisone is added with thorough stirring to assure uniform dipersion. The polymer is cast in the form of cylinders 1.5 cm by 3 cm and is cured at 70"C. After curing, the cylinders are removed from the mold and are suitable for implantation to provide prolonged release of cortisone.

EXAMPLE 16.

The polymer of Example 13 above is extruded to form a tube 1.5 m in length and tO mm in diameter. Dry nitrogen gas is passed through this tube and into a dry ice trap. The tube is then immersed in a trough of water. Water vapor which is picked up by the nitrogen as it flows through the tube is deposited in the trap as ice.

EXAMPLE 17.

A series of three polyurethane polyether resins is prepared in which the amount of Delta glucano-lactone is varied.

Polyethylene glycol Diethylene Delta HYLENE Dibutyl tin (M. Wt. 1450) glycol gluconolactone W dilaurate Resin (a) 54.6 g 8.7 g 2.9 g 40.4 g 0.04 g Resin (b) 54.6 g 8.7 g 5.8 g 40.4 g 0.04 g Resin (c) 54.6 g 8.7 g 11.6 g 48.5 g 0.04 g The polyethylene glycol and diethylene glycol are melted and mixed together m the absence of a solvent at 700 C. The delta glucanolactone and HYLENE W are then added and stirring is continued until the mixture is homogeneous. The mixture is cooled to 45" C. and the dibutyl tin dilaurate is added rapidly with stirring. Stirring is continued for about 15 minutes during which time the exothermic heat of reaction causes the temperature to rise to about 85" C. and the viscosity increases. The polymer.

is poured while still viscous into a chilling pan and placed in an oven at 750 C. for 20 minutes. The pan is then removed from the oven and cooled to room temperature.

The polymer may be removed from the pan and stored indefinitely at room tempera ture or used immediately as a molding resin. The resin will swell in methanol and may be dissolved in alkaline solutions.

EXAMPLE 18.

The resin (a) of Example 17 above is molded in the shape of a lens by placing in a water cooled mold sufficient resin to fill the cavity and applying 15,000 psi pressure at 125 C. The mold is cooled and the optically clear polymer lens is removed.

EXAMPLE 19.

One part of norethandrolone is blended with 30 parts of resin (b) of Example 18 on a Band mill at 400 G. This composition is placed in the cavity of a cylindrical mold and molded at 15,000 psi and 125 C. to form a cylinder of the polyurethane polyester resin having uniformly distributed throughout its mass a pharmacologically effective dosage of norethandrolone.

EXAMPLE 20.

A surgical suture is prepared by extruding the resin (b) of Example 17 through an orifice at 1.100 C. and 15,000 psi. The extruded monofilament is stretched four times, wound on a rack, annealed at 1000 G for one-half hour and cooled to room temperature. The resulting suture may be cut to length, packaged and sterilized by gamma irradiation. If an iodized suture is desired, the suture is immersed in a 10 weight percent solution of iodine in ethanol umil the desired amount of iodine has been taken up by the suture. Multifilament sutures may be produced as described above in this example by extruding the polymer of Example 17 (b) through a spinner ette containing the desired number of orifices and braiding the multifilament after it has been annealed.

EXAMPLE 21.

The polymer solution described above in Example 14 is cast on a flat glass surface to form a film that is air dried at room temperature. The dry film may be removed from the glass surface and applied directly to the surface of a burn as a bum dressing or the film may be comminuted and applied to the burn in the form of a powder.

EXAMPLE 22.

A surgical implant is prepared by blending one part of neo-B-vitamin A with 30 parts of the polyurethane polyether resin of Example 17 (a) on a band mill at 40 C. This composition is placed in the cavity of a cylindrical mold and molded at 15,000 psi and 125 C. to form a cylinder having uniformly distributed throughout its mass an effective dosage of neo-B-vitamin A. In a similar manner surgical implants may be molded containing a pharmacologically effective dosage of a hormone, a drug protagonist, an anti-tubercular drug or a steroid.

EXAMPLE 23.

One part of lactic acid is blended with 30 parts of the polyurethane polyether resin (c) of Example 17 on a band mill at 45" C. The composition is placed in the cavity of an annular mold and molded at 15,000 psi and 125 C. to form a polymer ring useful as an intrauterine device.

EXAMPLE 24.

The resin (c) of Example 17 is extruded through an annular orifice at 20,000 psi and 135 C. to form a cannula. The cannula is immersed for 24 hours in a 10 weight percent solution of iodine in ethanol after which time the iodine is distributed throughout the resin mass. The cannula is then removed from the iodine solution and air dried.

EXAMPLE 25.

A woven tube of textile fibers 3 mm in diameter is repeatedly dipped in the solution of polyurethane polyether resin described in Example 17 and air dried to fill the interstices between the strands with polyurethane polymer and produce a cannula useful in surgery.

Larger diameter tubes of woven polyethylene terphthalate strands may be similarly treated to fill the interstices between the woven strands. The resulting product may be used by the surgeon as a vascular prothesis.

EXAMPLE 26.

DBP dilaurate (a product identified as T12 manufactured by Metal and Thermite Company of Rahway, New Jersey) is added to the reaction mixture with stirring at a temperature below 45 OC. to avoid undue temperature rise caused by the heat of reaction.

After stirring for 20 minutes, the temperature increases to 800 C. The reaction mixture is then transferred to a tray and placed in an oven at 900 C. for 1 hour to complete the reaction. This polymer is amphoteric and, in the wet state, is soft, compliant and flexible.

WHAT I CLAIM IS: 1. A hydrophilic polyurethane polymer having lactone groups in the polymer backbone and comprising the reaction product of: (A) one or more diols selected from i(a) diethylene glycol, dipropylene glycol or a dihydric phenol, (b) long chain polyoxyalkylene diols having a molecular weight of at least 200, (c) linear polyester diols derived from the condensation of one or more diols with one or more dibasic acids, and (d) the reaction product of one or more alkylene diols or polyoxyalkylene diols with a difunctional linear polyester derived from the condensation of one or more diols with one or more dibasic acids; (B) a polyfunctional lactone having the formula

wherein R1 is -H, -CH2NH2, SO2CH3, --CHOHCOOH, or --(CHOH),CH,OH; n is 0 or an integer from 1 to 5; and R2 is a divalent radical --(CHOH),,-; m m being an integer from 2 to 10; and ethers derived from said lactones; and (C) a urethane precursor selected from organic polyisocyanates and nitrile carbonates.

2. A polyurethane polymer as claimed in Claim 1, wherein one of said diols is a functional linear polymer derived from the condensation of one or more diols with one or more dibasic acids.

3. A polyurethane polymer as claimed in Claim 1, wherein one of said diols is the reaction product of a polyoxyalkylene diol with a difunctional linear polyester derived from the condensation of diethylene glycol with adipic acid.

4. A surgical suture comprising a hydrophilic polyurethane polymer as claimed

Claims

in Claim 1.

5. A suture as claimed in Claim 4 ,wherein said hydrophilic polyurethane polymer is in the form of a monofilament.

6. A suture as claimed in Claim 4, wherein said hydrophilic polyurethane polymer is in the form of a braided multifilament.

7. A suture as claimed in Claim 4, having present in said hydrophilic polyurethane polymer a medicament.

8. A suture as claimed in Claim 7 wherein said medicament is iodine.

9. A burn dressing comprising a hydrophilic polyurethane polymer as claimed in Claim 1.

10. A burn dressing as claimed in Claim 9 wherein said hydrophilic polyurethane polymer is in the form of a fIlm.

11. A burn dressing as claimed in Claim 9 wherein said hydrophilic polyurethane polymer is in powder form.

12. A burn dressing as claimed in Claim 9 wherein said hydrophilic polyurethane polymer is in solution.

13. A burn dressing as claimed in Claim 10 having present in said hydrophilic polyurethane polymer a medicament.

14. A bum dressing as claimed in Claim 13 wherein said medicament is sulfadiazine.

15. A burn dressing as claimed in Claim 11 wherein a medicament is distributed throughout the powder.

16. A burn dressing as claimed in Claim 12 wherein a medicament is dissolved in said solution.

17. A surgical implant comprising a solid hydrophilic polyurethane polymer as claimed in Claim 1, said polyurethane polymer having distributed throughout its mass a medicament.

18. An implant as claimed in Claim 17 wherein said medicament is an antitubercular drug.

19. An implant as claimed in Claim 17 wherein said medicament is a drag protagonist.

20. An implant as claimed in Claim 17 wherein said medicament is a hormone.

21. An implant as claimed in Claim 17 wherein said medicament is a steroid.

22. An implant as claimed in Claim 17 wherein said medicament is a vitamin.

23. An intrauterine device comprising a hydrophilic polyurethane polymer as claimed in Claim 1.

24. An intrauterine device as claimed in Claim 23 in the shape of a ring.

25. An intrauterine device as claimed in Claim 23 having distributed throughout said polyurethane polymer a contraceptive.

26. An intrauterine device as claimed in Claim 25 wherein the contraceptive is lactic acid.

27. A cannula, the walls of which are formed of a hydrophilic polyurethane polymer as claimed in Claim 1.

28. A cannula as claimed in Claim 27 wherein said polyurethane polymer has distributed throughout its mass a medicament.

29. A cannula as claimed in Claim 28 wherein said medicament is iodine.

30. A cannula woven of textile fibers in the form of a tube having external and internal walls, at least one wall of which is coated with a film of a hydrophilic polyurethane polymer as claimed in Claim 1.

31. A vascular prosthesis comprising textile strands woven in the form of a tube; the interstices between said woven strands being filled with a hydrophilic polyurethane polymer as claimed in Claim 1.

32. A vascular prosthesis as claimed in Claim 31 wherein said polyurethane polymer has distributed throughout its mass a medicament.

33. A vascular prosthesis as claimed in Claim 31 wherein said textile strands are polyethylene terephthalate strands.

34. A vascular prosthesis as claimed in Claim 31 wherein said textile strands are collagen strands.

35. A vascular prosthesis as claimed in Claim 32 wherein said medicament is heparin.

36. A method of controlling dehydration in animals which comprises the oral administration of a hydrophilic polyurethane polymer as claimed in Claim 1.

37. An oral delivery system comprising a pharmacologically active agent and a hydrophilic polyurethane polymer as a carrier vehicle therefor, said hydrophilic polyurethane polymer being as claimed in Claim 1.

38. A solution effective in the repair of skin abrasions comprising a hydrophilic polyurethane polymer dissolved in a volatile non-toxic organic solvent, said polyurethane polymer being as claimed in Claim 1.

39. A cosmetic adapted for optical application comprising a solution of a nontoxic dye and a hydrophilic polyurethane polymer in a volatile non-toxis organic solvent, said polyurethane polymer being as claimed in Claim 1.

40. A surgical suture coated with a hydrophilic polyurethane polymer as claimed in Claim 1.

41. An eye bandage comprising a film of a hydrophilic polyurethane polymer as claimed in Claim 1.

42. A battery separator plate formed of a hydrophilic polyurethane polymer as claimed in Claim 1.

43. A hair spray composition comprising a solution in a volatile non-toxic solvent of a hydrophilic polyurethane polymer as claimed in Claim 1.

44. A gas permeable membrane formed of a hydrophilic polyurethane polymer as claimed in Claim 1.

45. A depilatory liquid comprising a solution in a non-toxic solvent of a depilatory agent and a hydrophilic polyurethane polymer as claimed in Claim 1.

46. A solution of a perfume and a hydrophilic polyurethane polymer in a nontoxic solvent, said polyurethane polymer comprising the reaction product as claimed in Claim 1.

47. A corneal prosthesis comprisin ga solid transparent hydrophilic polyurethane polymer as claimed in Claim 1, said polyurethane polymer being in the shape of a lens and characterized by a refractive index in the range of from 1.39 to 1.55, dry.

48. A deodorant composition comprising a solution of a disinfectant, a perfume and a hydrophilic polyurethane polymer as claimed in Claim 1.

49. A method of imparting moisture to a dry gas which comprises passing the gas through a tube formed of a hydrophilic polyurethane polymer as claimed in Claim 1.

50. An antifogging liquid containing in solution a hydrophilic polyurethane polymer comprising the reaction product as claimed in Claim 1.

51. A surgical drape comprising a fabric coated on at least one side with a hydrophilic polyurethane polymer as claimed in Claim 1.

52. A dialysis membrane formed of a hydrophilic polyurethane polymer comprising the reaction product as claimed in Claim 1.

53. A blood oxygenator which comprises a carbon dioxide-oxygen exchange membrane formed of a hydrophilic polyurethane polymer as claimed in Claim 1.

54. An amphoteric hydrophilic polyurethane polymer having lactone groups in the polymer backbone and comprising the reaction product of: (A) one or more diols selected from, (a) diethylene glycol, (b) long chain polyoxyalkylene diols having a molecular weight of at least 200, (c) difunctional linear polyesters derived from the condensation of one or more diols with one or more dibasic acids, and (d) the reaction product of one or more alkylene diols or polyoxyalkylene diols with a difunctional linear polyester derived from the condensation of one or more diols with one or more dibasic acids; (B) a polyfunctional lactone having the formula

wherein R1 is a monovalent radical selected from -H, ----CH2NH2, --SOCHd, --CHOHCOOH, and (CHOH)CH2OH; n is O or an integer from 1 to 5; and R2 is a divalent radical --(CHOH),,-; m being an integer from 2 to 10; and ethers derived from said lactones; (C) a urethane precursor selected from organic polyisocyanates and nitrile carbonates; and (D) a dialkanol tertiary gamine.

55. An esophageal prosthesis constructed of a fabric tube reinforced with a spirally wound polypropylene monofilament and coated on at least one side with a hydrophilic polyurethane polymer as claimed in Claim 1.

56. A contact lens comprising a molded hydrophilic polyurethane polymer as claimed in Claim 1.

57. A polyurethane polymer as claimed in Claim 1 which has a flow point below 275 G

58. A polyurethane polymer as claimed in Claim 1 which has free hydroxyl groups in the polymer backbone.

59. A polyurethane polymer as claimed in Claim 1 which has free carboxyl groups and free hydroxyl groups in the polymer backbone.

60. A polyurethane polymer as claimed in Claim 1 which has been molded to form a desired shape.

62. A coated device as claimed in Claim 61 wherein the substrate is a catheter.

61. A coated device consisting of a substrate coated with a hydrophilic polyurethane polymer as claimed in Claim 1.

63. A hydrophilic polyurethane polyether resin having lactone groups in the polymer backbone.

64. A polyurethane polyether resin as claimed in Claim 63 having free hydroxyl groups in the polymer backbone.

65. A hydrophilic polyurethane polyester resin characterized by a molecular weight above 6000 and having lactone groups in the polymer backbone, said urethane polymer comprising the reaction product of: (a) a polyfunctional lactone having the formula

wherein R1 is a monovalent radical selected from U, -CH2NH2, -SO2CH,, -CHOHCOOH, and (CHOH)CH2OH; n being 0 or an integer from 1 to 5; and R2 is a divalent radical -(CHOH)a, n being an integer from 4 to 10; and ethers derived from said lactones; (b) a polyalkylene oxide glycol; and (c) an organic polyisocyanate; said urethane polymer being soluble in alkaline solutions.

66. A polyurethane polyether resin as claimed in Claim 65 wherein said lactone is delta gluconolactone.

67. A polyurethane polyether resin as claimed in Claim 65 wherein said lactone is mannolactone.

68. A polyurethane polyether resin as claimed in Claim 65 wherein said lactone is sorbolactone.

69. A polyurethane polyether resin as claimed in Claim 65 wherein said lactone is D-glucuronolactone.

70. A polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene oxide is polyethylene glycol having a molecular weight of 1450.

71. A polyurethane polymer resin as claimed in Claim 65 wherein said polyalkylene oxide glycol is a mixture of polyethylene glycol and diethylene glycol.

72. A polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene glycol is a block copolymer polyol characterized by a molecular weight of about 4750; said block copolymer polyol being obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of about 950.

73. A polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene glycol is a block copolymer polyol characterized by a molecular weight of about 7500; said block copolymer polyol being obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of about 2250.

74. The polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene glycol is a block copolymer polyol characterized by a molecular weight of about 6510; said block copolymer polyol being obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of about 2250.

75. The polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene glycol is a block copolymer polyol characterized by a molecular weight of about 13,333; said block copolymer polyol being obtained by adding poly(oxyethylene) groups to a poly(oxypropylene) chain having a molecular weight of about 4000.

76. The polyurethane polyether resin as claimed in Claim 65 wherein said polyalkylene oxide glycol is polypropylene glycol.

77. The polyurethane polyether resin as claimed in Claim 65 wherein said polyisocyanate is methylene di(cyclohexylisocyanate).

78. The polyurethane polyether resin as claimed in Claim 65 wherein said poly alkylene oxide glycol is a polyethylene oxide glycol having a molecular weight of at least 200.

79. A hydrophilic polyurethane polyether resin having lactone groups in the polymer backbone and obtained by reacting a mixture of polyethylene glycol, diethylene glycol, delta gluconolactone and methylene di(cyclohexylisocyanate) in the presence of a catalyst.

80. A polyurethane polyether resin as claimed in Claim 79 obtained by reacting a mixture of about 54.6 parts by weight of polyethylene glycol (M. Wt. 1450), about 8.7 parts by weight of diethylene glycol, about 5.8 parts by weight of delta gluconolactone and about 40.4 parts by weight of methylene di(cyclohexylisocyanate) in the presence of about 0.5 parts by weight dibutyl tin dilaurate.

81. A polyurethane polymer as claimed in Claim 1 and substantially as hereinbefore described with reference to any of the Examples.