EA048599B1 - MOLDED POLYURETHANE HYDROGELS - Google Patents

Description

Field of the invention

The present invention relates to polyurethane hydrogels based on polyethers and polyesters and to their use in condoms.

Cross reference to related application

This application claims the benefit of Australian Provisional Patent Application No. 2019902307, which is incorporated herein by reference in its entirety.

Prior art of the present invention

Condoms are often thought of as contraceptives, but their action as a physical barrier also serves an important health function by reducing or preventing sexually transmitted diseases such as herpes, chlamydia, syphilis, gonorrhea, hepatitis, human papillomavirus (HPV), trichomoniasis, and acquired immunodeficiency syndrome (AIDS) caused by the human immunodeficiency virus (HIV).

Condoms are commonly made of latex, although nitrile, nitrile rubber, polyurethane, AT-10 resin (polyethylene resin), and polyisoprene may also be used. Disadvantages of latex condoms and gloves include allergic reactions to the material and the sensitivity of latex rubber to oil-based lubricants, resulting in potential for breakage and disease transmission. In addition, latex, like other commonly used materials, has a high coefficient of friction, resulting in reports of decreased sensation during use. This may reduce condom use and increase the likelihood of disease transmission. Polyurethane has some advantages over latex, including the ability to be used with oil-based lubricants, being less allergenic than latex, and being odorless. However, polyurethane condoms are less elastic than latex condoms and are more likely to slip or break, lose shape, or wrinkle.

Protective gloves are typically made using latex rubber, nitrile or nitrile rubber (a synthetic copolymer of acrylonitrile and butadiene), polyvinyl alcohol, and polychloroprene. These materials provide varying degrees of protection against materials such as organic solvents, inorganic compounds, and other hazardous materials, but provide only limited thermal and physical protection.

The present inventors have developed methods for producing molded polyurethane hydrogels that are substantially impermeable to biological agents and have sufficient strength and durability to be suitable for use in the manufacture of protective equipment such as condoms and gloves.

The essence of the present invention

According to a first aspect, a method for producing a molded polyurethane hydrogel is provided, the method comprising obtaining a first solution comprising at least one polyurethane having a molecular weight of from about 40,000 to about 500,000 in a mixture of water and an organic polar solvent containing less than about 40% v/v water;

applying a layer of the first solution to the form;

drying a layer of the first solution to form a polyurethane film on the mold; and contacting the polyurethane film with a swelling agent under conditions such that the film forms a polyurethane hydrogel with a swelling agent content of from about 1% to about 95%.

According to an embodiment, the molecular weight of the polyurethane is from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

According to a preferred embodiment, the molecular weight of the polyurethane is from about 150,000 to about 350,000.

According to an embodiment, the polyurethane is obtained by polymerizing 4,4'dicyclohexylmethane diisocyanate.

According to an embodiment, the polyurethane is a polyether or polyester-based polyurethane.

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According to an embodiment, the polyether-based polyurethane is obtained by polymerizing 4,4'-dicyclohexylmethane diisocyanate and a polyether.

According to an embodiment, the polyether contains from 1 to 35 ethyl ether groups.

According to an embodiment, the polyester-based polyurethane is obtained by polymerizing 4,4'-dicyclohexylmethane diisocyanate and a polyester.

According to an embodiment, the polyester contains from 1 to 35 ethyl ester groups.

According to an embodiment, the polyurethane may contain methyl and/or hydroxyl end groups.

According to an embodiment, the organic polar solvent is selected from the group consisting of ethanol, methanol, isopropanol, butanol, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, acetone, acetonitrile and any combination thereof.

According to an embodiment, the organic polar solvent is ethanol.

According to an embodiment, the ratio of water to organic polar solvent is selected to be from about 5:95, about 10:90, about 15:85, about 20:80, about 25:75, about 30:70, about 35:65, or about 40:60.

According to an embodiment, the ratio of water to organic polar solvent is approximately 10:90.

According to an embodiment, at least one agent is selected as the swelling agent, which is water, a glycol solution, a hydroxyethylcellulose solution, a paraben-based solution, a glycol-based solution, a glycerol-based solution, an oil-based solution, or an organosilicon-based solution.

According to an embodiment, the swelling agent comprises one or more of the following agents: a spermicidal agent, a lubricant, an antiviral agent, an antifungal agent, an antimicrobial agent, a prebiotic agent, a probiotic agent, a microbiome enhancer, a flavor additive, a fragrance additive, a sensation enhancing agent, a sterilizing agent, and a disinfectant.

According to an embodiment, the polyurethane film is in contact with the swelling agent for from about 1 to about 30 s. According to some embodiments, the polyurethane film is in contact with the swelling agent for up to 24 hours, such as about 15 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours, about 12 hours, about 13 hours, about 14 hours, about 15 hours, about 16 hours, about 17 hours, about 18 hours, about 19 hours, about 20 hours, about 21 hours, about 22 hours, about 23 hours, or about 24 hours.

According to an embodiment, the temperature of the swelling solution is from about 20°C to about 90°C. For example, the temperature can be about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, or about 90°C.

According to an embodiment, the method further comprises providing a second solution comprising a polyurethane having a molecular weight of from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000, in a mixture of water and an organic polar solvent containing less than about 40% v/v water;

applying a layer of the second solution to the polyurethane film on the form;

drying a layer of the second solution, wherein the layers form a polyurethane film on the mold; and contacting the polyurethane film with a swelling agent under conditions such that the film forms a polyurethane hydrogel containing the swelling agent

- 2 048599 agent, comprising from approximately 1% to approximately 95%.

According to one embodiment, the polyurethane comprises -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -[OOCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-(CH ₂ CH ₂ -O-CH ₂ CH ₂ )-O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -OCH ₂ ) _n -CH ₂ -, wherein n is an average value that is independently selected from any number from 1 to 35; and m represents the mean value, which is independently chosen to be any number from 15 to 500.

In some embodiments, the relationship between the numbers n and m may be their ratio.

In some embodiments, the ratio of the numbers n and m may be from about 1:0.1 to about 1:75.

In some embodiments, the at least one polyurethane in the second solution may not be the same as the at least one polyurethane in the first solution.

According to an embodiment, the method further comprises applying a subsequent layer of the first or second solution to the polyurethane film on the mold to increase the thickness or to create a specific feature of the polyurethane film.

According to an embodiment, the method further comprises applying a subsequent layer of the first or second solution to a portion of the polyurethane film on the mold to increase the thickness or to create a specific feature on the portion of the polyurethane film.

The specific feature formed by the subsequent layer has different modulus, tensile strength and/or linear expansion range values than the hydrogel formed from the layer to which it is applied.

According to an embodiment, one or both of the molecular weight and the ratio of the n and m numbers of at least one polyurethane in the first solution differ from the molecular weight and/or the ratio of the n and m numbers of at least one polyurethane in the second solution.

According to an embodiment, additional subsequent layers are applied to increase the thickness to a specified value.

According to an embodiment, the molded polyurethane hydrogel has a linear expansion range of from about 1% to about 100%.

According to an embodiment, the molded polyurethane hydrogel has a tensile strength of from about 1 MPa to about 20 MPa, from about 20 MPa to 40 MPa, from about 40 MPa to about 60 MPa, from about 80 MPa to about 100 MPa.

According to a preferred embodiment, the molded polyurethane hydrogel has a tensile strength of about 20 MPa to 40 MPa, such as 20 MPa, 22 MPa, 24 MPa, 26 MPa, 28 MPa, 30 MPa, 32 MPa, 34 MPa, 36 MPa, 38 MPa, or about 40 MPa.

According to an embodiment, the molded polyurethane hydrogel has a relative elongation at break in the range of from about 200% to about 2000%.

According to an embodiment, the molded polyurethane hydrogel has an elastic modulus at 50% elongation from about 80 kPa to about 15 MPa, an elastic modulus at 100% elongation from about 200 kPa to about 15 MPa, and an elastic modulus at 300% elongation from about 700 kPa to about 15 MPa.

According to the second aspect, a molded polyurethane hydrogel condom is proposed, manufactured by the method according to the first aspect.

According to a third aspect, a molded polyurethane hydrogel condom is provided, wherein the polyurethane hydrogel comprises one or more polyurethanes having a molecular weight of from about 40,000 to about 500,000 and a swelling agent content of from about 1% to about 95%.

According to an embodiment, the molecular weight of the polyurethane is from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

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According to an embodiment, the polyurethane is obtained by polymerizing 4,4'dicyclohexylmethane diisocyanate.

According to an embodiment, the polyurethane is a polyether or polyester-based polyurethane.

According to an embodiment, the polyether-based polyurethane is obtained by polymerizing 4,4'-dicyclohexylmethane diisocyanate and a polyether.

According to an embodiment, the polyether contains from 1 to 35 ethyl ether groups.

According to an embodiment, the polyester-based polyurethane is obtained by polymerizing 4,4'-dicyclohexylmethane diisocyanate and a polyester.

According to an embodiment, the polyester contains from 1 to 35 ethyl ester groups.

According to an embodiment, the molded polyurethane hydrogel condom has one or more parameters from the range of linear expansion from about 1% to about 100%, tensile strength from about 1 MPa to about 100 MPa, relative elongation at break in the range from about 200% to about 2000%, and at least one parameter from the modulus of elasticity at 50% elongation from about 80 kPa to about 15 MPa, the modulus of elasticity at 100% elongation from about 200 kPa to about 15 MPa and the modulus of elasticity at 300% elongation from about 700 kPa to about 15 MPa.

According to an embodiment, the condom is substantially impermeable to biological agents having an average diameter of 30 nm or more.

According to an embodiment, the condom is substantially impermeable to biological agents having an average diameter of 30 nm or more under conditions of a simulated application pressure of up to about 10 kilopascals and applied to the condom, for example, the simulated application pressure can be up to about 1 kPa, up to about 2 kPa, up to about 3 kPa, up to about 4 kPa, up to about 5 kPa, up to about 6 kPa, up to about 7 kPa, up to about 8 kPa, up to about 9 kPa, or up to about 10 kPa.

According to an embodiment, the condom has an air volume at burst of from approximately 5 L to approximately 50 L.

According to an embodiment, the condom has an air pressure at burst of from about 1 kPa to about 5 kPa, such as from 1.3 kPa to about 3.6 kPa.

Definitions

Throughout the description of the present invention, unless the context clearly requires otherwise, the word include or its grammatical forms such as includes or including, shall be understood to mean the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Throughout the description of the present invention, the term “consisting of” means the presence of only the listed elements.

Any discussion of documents, acts, materials, devices, articles or similar items mentioned in the description of the present invention are provided solely for the purpose of providing context for the present invention. It should not be taken as an admission that any or all of the said items form part of the relevant prior art or are generally known in the art to which the present invention pertains, as if they existed prior to the priority date of each of the claims of the present invention.

Unless the context otherwise requires or is specifically indicated, integers, steps or elements of the present invention that are referred to herein in the singular form as integers, steps or elements specifically include both the singular and the plural forms of those integers, steps or elements.

In the context of the description of the present invention, grammatical forms of the singular are used to designate one or more than one (i.e. at least one) object designated by a given grammatical form. As an example, the term element means one element or more than one element.

In the context of the description of the present invention, the term approximately means that the number or value referred to is not to be taken as an absolute number or value, but that upper and lower limits of variability of the said number or value are provided, which correspond to what a person skilled in the art should understand according to the specifications, which are within typical error ranges or instrumental limitations. In other words,

- 4 048599 by you, the use of the term approximately should be understood as designating ranges or approximations that a person skilled in the art would typically consider equivalent to the presented values in the context of providing the same functions or results.

Those skilled in the art will understand that other variations and modifications than those specifically described may be made to the present invention as described herein. It should be understood that the present invention encompasses all such variations and modifications. For the avoidance of doubt, the present invention also encompasses all steps, features and compounds that are mentioned or indicated in the description of the present invention, including individually or collectively, as well as any and all combinations of any two or more of the above-mentioned steps, features and compounds.

In order to make the present invention more clear and understandable, preferred embodiments thereof will be described with reference to the following figures and examples.

Brief description of the drawings

Fig. 1 shows an exemplary curve of the dependence of elongation on load for a hydrogel made using a polymer containing polymer A. The condom has a double wall thickness of 0.125 mm and a width of 58 mm. The width of the ring-shaped sample is 20 mm.

Fig. 2 shows an exemplary curve of the dependence of elongation on load for a hydrogel made using a polymer containing polymer B. The condom has a double wall thickness of 0.148 mm and a width of 53 mm. The width of the ring-shaped sample is 20 mm.

Detailed disclosure of embodiments of the present invention

The present invention is based on methods for producing molded polyurethane hydrogels (including those based on simple polyesters or those based on complex polyesters. Hydrogels produced by these methods exhibit a number of properties such as linear expansion, tensile strength, range of relative elongation at break, modulus and impermeability with respect to biological agents, and these properties, present individually or in combination, make the hydrogels suitable for use in protective equipment such as condoms and gloves.

The methods described herein require the preparation of a solution which is a solution of polyurethane in a mixture of water and an organic polar solvent. A layer of the solution is then applied to a mould, for example by immersing the mould in the solution. After the layer is applied, it dries and forms a polyurethane film on the mould. One or more additional layers of the same solution or different solutions (for example, using different polyurethanes) can then be applied. After the layers have dried, the film can then be contacted with a swelling agent, which is, for example, an aqueous solution that can contain a buffer, a salt and/or a preservative. The swelling agent is infiltrated into the film in such a way that a polyurethane hydrogel is formed, the hydrogel typically having a swelling agent content of from about 1% to about 95%, but typically about 30 to 90% for water-based swelling agents. In the case of oil- or silicone-based swelling agents, the hydrogel typically has a swelling agent content of from about 0.1% to about 30%, such as from about 0.1% to about 10%, after contact with the swelling agent for 24 hours.

Polyurethane

As used herein, the term polyurethane means a polymer obtained by the reaction of an isocyanate and an alcohol, wherein the isocyanate contains two or more isocyanate functional groups.

A variety of polyurethanes can be used in the methods described herein. Suitable polyurethanes are those prepared by polymerizing 4,4'-dicyclohexylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate and a polyether, 4,4'-dicyclohexylmethane diisocyanate and a polyester, or any combination thereof.

According to an embodiment, the polyurethane is a hydrophilic polyurethane block copolymer, such as a hydrophilic polyurethane block copolymer comprising 4,4' dicyclohexylmethane diisocyanate. The hydrophilic polyurethane block copolymer may comprise repeating ethyl ether groups, for example, the hydrophilic polyurethane block copolymer comprises at least 1 to 50 repeating ethyl ether groups.

According to another embodiment, the hydrophilic polyurethane block copolymer is a polyether-based polyurethane. For example, the hydrophilic polyurethane block copolymer comprises 4,4'-dicyclohexylmethane diisocyanate and an ethyl ether. The hydrophilic polyurethane block copolymer may comprise 4,4'-dicyclohexylmethane diisocyanate and repeating ethyl ether groups, for example, at least four may be present

- 5,048,599 repeating ethyl ether groups. According to a further embodiment, the hydrophilic polyurethane block copolymer comprises 4,4'-dicyclohexylmethane diisocyanate and from 1 to 35 repeating ethyl ether groups.

The hydrophilic polyurethane block copolymer may comprise repeating ethyl ester groups, for example, the hydrophilic polyurethane block copolymer may comprise at least 1 to 35 repeating ethyl ester groups.

According to another embodiment, the hydrophilic polyurethane block copolymer is a polyester-based polyurethane. For example, the hydrophilic polyurethane block copolymer comprises 4,4'-dicyclohexylmethane diisocyanate and an ethyl ester. The hydrophilic polyurethane block copolymer may comprise 4,4'-dicyclohexylmethane diisocyanate and repeating ethyl ester groups, for example, at least four repeating ethyl ester groups may be present. According to another embodiment, the hydrophilic polyurethane block copolymer comprises 4,4'-dicyclohexylmethane diisocyanate and from 1 to 35 repeating ethyl ester groups.

According to an embodiment, the polyurethane has a molecular weight of from about 40,000 to about 500,000, for example, the molecular weight can be from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

According to an embodiment, the hydrophilic polyurethane block copolymer has a molecular weight of from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

According to an embodiment, the polyester-based polyurethane has a molecular weight of from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

According to an embodiment, the polyether polyurethane has a molecular weight of from about 40,000 to about 50,000, or from 50,000 to about 75,000, or from 75,000 to about 100,000, or from 100,000 to about 125,000, from about 125,000 to about 150,000, from about 150,000 to about 175,000, from about 175,000 to about 200,000, from about 200,000 to about 225,000, from about 225,000 to about 250,000, from about 250,000 to about 275,000, from about 275,000 to about 300,000, from about 300,000 to about 3,250,000, from about 325,000 to about 350,000, from about 350,000 to about 375,000, from about 375,000 to about 400,000, from about 400,000 to about 425,000, from about 4,250,000 to about 450,000, from about 450,000 to about 475,000, or from about 475,000 to about 500,000.

According to an embodiment, the polyurethane comprises -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -[O

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OCHN(C6Hio)CH ₂ (C6Hio)NHCO-0-(CH ₂ CH ₂ -0-CH ₂ CH ₂ )-0-OCHN(C6Hio)CH ₂ (C6Hio)NHCO-NH(C6H1o)CH ₂ (C6H1o)NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -O-OCHN(C6H1o)CH ₂ (C6H1o)NHCO-O] _m -CH ₂ -(CH ₂ -OCH ₂ ) _n -CH ₂ -, where n is independently selected to be any number from 1 to 35, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 20, 32, 32, 33, 34, or 35; and m is independently selected to be any number from 15 to 500, such as 15, 25, 50, 75, 100, 125, 150, 175, 200, 225, 25, 275, 300, 325, 350, 375, 400, 425, 450, 475, or 500.

According to some embodiments, one or both of the numbers n and m represent average values.

According to one embodiment, n is an average value of 1.5, and m is from 10 to 20, such as 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. According to one embodiment, m is 15.

According to one embodiment, n is an average value of 4 and m is an average value of 100 to 120, such as 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119 or 120. According to one embodiment, m is 108.

According to one embodiment, n is an average value of 5 and m is an average value of 105 to 130, such as 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129 or 130. According to one embodiment, m is 110.

In one embodiment, n is an average value of 34 and m is an average value of 75 to 85, such as 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, or 85. In one embodiment, m is 80.

According to one embodiment, n is an average value of 4 and m is an average value of 180 to 220, such as 180, 182, 184, 186, 190, 192, 194, 196, 198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, or 220.

According to one embodiment, n is an average value of 30.5 and m is an average value of 140 to 160, such as 140, 142, 148, 150, 152, 154, 156, 158, or 160.

According to one embodiment, n is an average value of 7 and m is an average value of 200 to 240, such as 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 238, or 240.

According to one embodiment, methyl and hydroxyl groups are independently selected as the end groups of the polyurethane.

Water and organic polar solvent

In the methods described herein, a solution of polyurethane in a mixture of water and an organic polar solvent must be prepared. The polyurethane may be solubilized in the solvent before adding water, or the polyurethane may be solubilized in a mixture of water and an organic polar solvent.

The polar solvent may be a protic or aprotic solvent. The solvent may be any lower aliphatic alcohol or chlorinated solvent. For example, the solvent may be selected from the group consisting of ethanol, methanol, isopropanol, butanol, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, acetone, acetonitrile, and any combination thereof.

The ratio of water to organic solvent may be about 5:95, about 10:90, about 15:85, about 20:80, about 25:75, about 30:70, about 35:65, or about 40:60.

The mixture of water and an organic solvent used to obtain the polyurethane solution may be at room temperature or at an elevated temperature of, for example, from about 25°C to about 60°C, for example, the solution in the mixture of water and an organic solvent can be heated to a temperature of about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, or about 60°C.

The concentration of the polyurethane in the mixture of water and the organic polar solvent is from about 1% to about 20% w/v, for example, this concentration can be about 1% w/v, about 2% w/v, about 3% w/v, about 4% w/v, about 5% w/v, about 6% w/v, about 7% w/v, about 8% w/v, about 9% w/v, about 10% w/v, about 11% w/v, about 12% w/v, about 13% w/v, about 14% w/v, about 15% w/v, about 16% w/v, about 17% w/v, about 18% w/v, about 19% w/v. or about 20% w/v. According to one embodiment, the polyurethane is present at a concentration of about 6% w/v.

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Forms

The methods described herein require applying a polyurethane solution to a mold. The mold of any configuration can be used to make articles such as condoms, gloves, films, or other articles and devices. In some embodiments, an existing device (such as a condom) can be used as a mold.

For example, the mold may be a core, a mold, a plate, or a sheet. In embodiments where condoms are to be manufactured, the mold may be a cylinder or a phallus.

In some embodiments, glass, a ceramic material (e.g., TiN), a plastic material, a metal, or a combination of materials or coatings are used to make the mold.

According to an embodiment, the mold is heated. For example, the mold can be heated to any temperature up to about 90°C using convection, infrared radiation, electromagnetic induction, or conduction.

The polyurethane solution is applied to the mold to form a layer of the solution on at least a part of the mold. This can be done, for example, by dipping the mold into the solution or by spraying, pouring, injecting, applying the solution with a brush or roller onto the surface or into the mold, or any combination of these methods.

The polyurethane solution may be applied to the mold at room temperature, or it may be heated before being applied to the mold. For example, the polyurethane solution may be heated to a temperature of approximately 37°C (with or without stirring) before being applied to the mold.

In some embodiments, the mold remains stationary during the application of the solution. In other embodiments, the mold is in motion during the application of the polyurethane solution.

According to an embodiment, the mold is immersed in the polyurethane solution at a speed of from about 1 mm/s to about 1000 mm/s. For example, the immersion speed can be about 1 mm/s, about 50 mm/s, about 100 mm/s, about 200 mm/s, about 300 mm/s, about 400 mm/s, about 500 mm/s, about 600 mm/s, about 700 mm/s, about 800 mm/s, about 900 mm/s, or about 1000 mm/s.

According to an embodiment, the mold is removed from the polyurethane solution at a speed of from 1 mm/s to about 1000 mm/s. For example, the removal speed can be about 1 mm/s, about 50 mm/s, about 100 mm/s, about 200 mm/s, about 300 mm/s, about 400 mm/s, about 500 mm/s, about 600 mm/s, about 700 mm/s, about 800 mm/s, about 900 mm/s, or about 1000 mm/s.

Varying the immersion and/or extraction speed can be used to control the thickness of the polyurethane film.

After applying a layer of polyurethane solution to the mold, the solution is dried to form a film on the mold. Drying can be accomplished by evaporation in an open atmosphere or in an oven or evaporator.

In some embodiments, drying may occur while the mold remains stationary. In other embodiments, drying may occur while the mold is in motion.

In some embodiments, the mold is heated to facilitate drying. For example, the mold can be heated to about 90°C using convection, infrared radiation,

The polyurethane solution can be dried at room temperature or at an elevated temperature, for example, from about 25°C to about 90°C. The elevated temperature can be about 25°C, about 30°C, about 35°C, about 37°C, about 40°C, about 45°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, or about 90°C.

Once the film is formed on the mold, additional applications of the polyurethane solution may be made. In some embodiments, a plurality of polyurethane solutions may be used. For example, a first polyurethane solution (obtained, for example, using a polyurethane having a molecular weight of about 40,000 to about 500,000) may be applied. Then, a second application may be made using the same solution or a different solution (using a polyurethane having a molecular weight of about 40,000 to about 500,000). Further applications of polyurethane solutions may also be made. For example, two, three, four, five, six or more may be made.

- 8 048599 cycles of applying the polyurethane solution and drying the solution. Thus, any number of the described polyurethane solutions can be used to produce a multilayer polyurethane film on a mold.

According to some embodiments, the polyurethane solution can be applied to the entire mold or to a portion of the mold. For example, the polyurethane solution can be applied to a portion of the mold or to a portion of the polyurethane film on the mold in order to increase the thickness of the film on the portion of the mold or to create a specific feature, such as ribbing, on the portion of the mold or the polyurethane film on the mold.

All layers of the multilayer polyurethane film may exhibit different physical properties. For example, a polyurethane solution that by itself may be, for example, too weak for making a condom, but has desirable properties such as a skin-like feel, and can be used in combination with one or more other polyurethane solutions for the purpose of making a multilayer polyurethane film on a mold. One or more layers may provide at least one of the properties of tensile strength, linear expansion and elastic modulus, and the other layers provide, for example, a skin-like feel or a wet skin-like feel.

According to one embodiment, the condom is manufactured using at least two different polyurethane solutions, such as for the inner and outer layers made of different polyurethanes. According to this embodiment, each layer has properties that provide different sensations on each side of the condom. For example, different polyurethanes may have different values of elastic modulus, tensile strength, linear expansion range and/or relative elongation at break.

In some embodiments, interlayer adhesion may be required for the application of different polymer solutions. This adhesion may be achieved by applying a polyurethane solution to the dried film such that a portion of the dried film is solubilized, or the applied solution diffuses into the dried film. Alternatively, the adhesive agent may be applied to the film before the next polyurethane solution is applied.

According to some embodiments, the polymer solutions can be molded to form non-hydrogel materials as a layer for the structure and/or features. For example, the polymer solutions can be molded to form latex, polyisoprene, non-hydrating polyurethanes, and other typical or atypical materials for devices, including condoms.

The polymer solution may be applied to the entire mold or to a portion of the interior or exterior of the non-hydrogel agent, such as the interior, interior or exterior of a device such as a condom.

The initial polymer film or multilayer film may be dried prior to the application of the subsequent polyurethane solution. Alternatively, subsequent amounts of polyurethane solution may be applied without drying the previously applied solution.

According to some embodiments, multiple applications of the polyurethane solution can be used to produce a polyurethane film of a given thickness, such as from about 50 to about 200 μm. The given thickness can be about 10 μm, about 20 μm, about 30 μm, about 40 μm, about 50 μm, about 60 μm, about 70 μm, about 80 μm, about 90 μm, about 100 μm, about 110 μm, about 120 μm, about 130 μm, about 140 μm, about 150 μm, about 160 μm, about 170 μm, about 180 μm, about 190 μm, or about 200 μm. According to some embodiments, the given thickness is from about 70 μm to about 80 μm.

Swelling agent

The methods described herein require contacting a polyurethane film or a multilayer polyurethane film with a swelling agent under conditions such that the film forms a polyurethane hydrogel.

The swelling agent may comprise water or consist of water. According to other embodiments, the swelling agent may be one or more agents that are an aqueous solution, a hydroxyethylcellulose solution, a paraben-based solution, a glycol-based solution, a glycerol-based solution, an oil-based solution, or an organosilicon-based solution. According to some embodiments, the swelling agent may be one or more solutions.

According to one embodiment, the swelling agent is water.

The swelling agent may contain a spermicide, lubricant

- 9 048599 agent, antiviral agent, antifungal agent, antimicrobial agent, prebiotic agent, probiotic agent, microbiome enhancer, flavor additive, aromatizing additive, sensation enhancing agent, sterilizing agent or disinfectant.

The polymer film may be dipped into the swelling agent and immediately removed from it. Alternatively, the polymer film or agent may be dipped into the swelling agent and kept in contact with the swelling agent for a period of time before being removed. The polymer film or agent may remain on the mold while in contact with the swelling agent; alternatively, the polymer film may be removed from the mold before coming into contact with the swelling agent.

According to some embodiments, the polyurethane film is in contact with the swelling agent for about 1 to about 60 s. After that, additional contact with the swelling agent can be carried out immediately or later.

According to other embodiments, the polyurethane film is in contact with the swelling agent overnight and up to about 24 hours. For example, the polyurethane film can be in contact with the swelling agent for about 15 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours, about 12 hours, about 13 hours, about 14 hours, about 15 hours, about 16 hours, about 17 hours, about 18 hours, about 19 hours, about 20 hours, about 21 hours, about 22 hours, about 23 hours, or about 24 hours.

In some embodiments, the polyurethane film is in contact with the swelling agent until the polyurethane hydrogel reaches maximum swelling. In some cases, the duration of this contact may be greater than 24 hours.

According to an embodiment, the temperature of the swelling agent is room temperature or is from about 20°C to about 90°C. Increasing the temperature of the swelling agent can reduce the time required for swelling of the polyurethane film to form a polyurethane hydrogel. Accordingly, the temperature of the swelling agent can be about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, or about 90°C.

Polyurethane hydrogel

The polyurethane hydrogel that is formed by contacting the polyurethane film with the swelling agent may have a swelling agent content of from about 1% to about 95%, such as about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95%. According to some embodiments, the swelling agent content is about 45%, about 50%, or about 55%, such as about 54%. According to some embodiments, the hydrogel has a swelling agent content that is approximately or exactly the same as the water content of the skin. Typically, the water content of the skin is approximately 64%; accordingly, according to some embodiments, the swelling agent content of the polyurethane hydrogel is from about 60% to about 70%, such as about 64%.

According to some embodiments, the swelling agent is an oil-based or silicone-based agent. According to these embodiments, the polyurethane hydrogel that is formed by contacting the polyurethane film with the silicone-based or oil-based swelling agent preferably has a swelling agent content of from about 0.1% to about 30%, such as about 1%, about 2%, about 4%, about 8%, about 10%, about 12%, about 14%, about 16%, about 18%, about 20%, about 22%, about 24%, about 26%, about 28%, or about 30%. For example, the polyurethane hydrogel may have a silicone-based or oil-based swelling agent content of from about 0.1% to about 10%, such as about 0.1%, about 0.5%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, or about 10% after contact with the swelling agent for 24 hours.

- 10 048599

In some embodiments, the swelling agent is a mixture or composition comprising two or more swelling agents on different bases. For example, in some embodiments, the swelling agent is a composition of swelling agents on an aqueous base and an organosilicon base.

The polyurethane hydrogel produced by the methods described herein has a number of properties that make it suitable for use in various articles such as condoms. These properties include suitable values of linear expansion, tensile strength, elastic modulus, ability to stretch substantially before breaking while being impermeable to biological agents and permeable to small molecules.

These properties can be modulated by selecting one or more of the following parameters: polymer type, polymer molecular weight range, average molecular weight, n/m ratio range for each polymer, or by blending two or more polymers. According to some embodiments, higher molecular weight polymers produce hydrogels that are stronger but also stiffer and less flexible, while lower molecular weight polymers produce hydrogels that are less strong but also softer and more flexible. Accordingly, by blending polymers and selecting polymers having one or more specific parameters, being average molecular weight, molecular weight profile, and n/m ratio, using the methods described herein, a hydrogel can be produced that has a desired range of properties such as linear expansion, tensile strength, elastic modulus, extensibility, and impermeability that are appropriate for a specific application, such as a condom. In addition to the amount and type of swelling agent contained in the hydrogel, these properties affect how the user feels the hydrogel, that is, they contribute to the feel of the hydrogel.

According to one embodiment, the properties can be modulated by using polymers having different n and m values or specific ratios of n and m numbers. For example, the ratio of n and m numbers affects the degree of swelling of the hydrogel, which in turn affects the elastic modulus, which in turn is associated with the sensation of the hydrogel. It should be noted that although the elastic modulus makes an important contribution to the sensation of the hydrogel, other properties and factors, such as the content and type of swelling agent, also contribute to the sensation.

According to some embodiments, the ratio of the numbers n and m is from 1:0.1 to 1:75. For example, a suitable ratio of the numbers n and m is 1:21-26 (corresponding to A in example 1), 1:25-30 (corresponding to B in example 1), 1:6.67-13.33 (corresponding to C in example 1), 1:2.2-2.5 (corresponding to D in example 1), 1:4.59-5.25 (corresponding to E in example 1), 1:28.57-34.30 (corresponding to F in example 1). Taking into account that, according to some embodiments, n and m are average values, the ratios of the numbers n and m also represent the ratios of the average value of n and the average value of m.

According to some embodiments, the ratio of the numbers n and m is approximately a ratio of one to any number between 0.1 and 75, such as 1:0.1, approximately 1:0.5, approximately 1:1, approximately 1:5, approximately 1:10, approximately 1:15, approximately 1:20, approximately 1:25, approximately 1:30, approximately 1:35, approximately 1:40, approximately 1:45, approximately 1:50, approximately 1:55, approximately 1:60, approximately 1:65, approximately 1:70, or approximately 1:75.

The term linear expansion means the ratio of the change in length to the original length of the agent. According to an embodiment, the polyurethane hydrogel film or agent has a linear expansion of from about 1% to 100%, such as about 10%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% or about 100%.

The term tensile strength refers to the maximum force that a specimen can withstand before the specimen breaks. Tensile strength is the ratio of the maximum force to the initial cross-sectional area of the specimen. According to an embodiment, the hydrogel agent has a tensile strength of from about 1 MPa to about 100 MPa, such as about 3 MPa, about 4 MPa, about 5 MPa, about 6 MPa, about 7 MPa, about 8 MPa, about 9 MPa, about 10 MPa, about 11 MPa, about 12 MPa, about 13 MPa, about 14 MPa, about 15 MPa, about 16 MPa, about 17 MPa, about 18 MPa, about 20 MPa, about 25 MPa, about 30 MPa, about 35 MPa, about 40 MPa, about 45 MPa, about 50 MPa, about 55 MPa, about 60 MPa, about 65 MPa, about 70 MPa, at

- 11 048599 approximately 75 MPa, approximately 80 MPa, approximately 85 MPa, approximately 90 MPa, approximately 95 MPa or approximately 100 MPa.

The term elastic modulus, as used herein, means the force at a specific elongation value and relates to the rigidity of the agent. According to an embodiment, the hydrogel agent has an elastic modulus at 50% elongation of about 80 kPa to about 15 MPa, an elastic modulus at 100% elongation of about 200 kPa to about 15 MPa, and an elastic modulus at 300% elongation of about 700 kPa to 15 MPa.

According to one embodiment, the modulus of elasticity at 50% elongation is from about 80 kPa to about 15 MPa, such as 80 kPa, 100 kPa, 500 kPa, 750 kPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 12 MPa, 13 MPa, 14 MPa, or 15 MPa.

According to one embodiment, the modulus of elasticity at 100% elongation is from about 200 kPa to about 156 MPa, for example, and 200 kPa, 250 kPa, 500 kPa, 750 kPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 12 MPa, 13 MPa, 14 MPa or 15 MPa.

According to one embodiment, the modulus of elasticity at 300% elongation is approximately 700 kPa to 15 MPa, such as 700 kPa, 750 kPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 12 MPa, 13 MPa, 14 MPa, or 15 MPa.

The term elongation at break means the maximum linear extension of an agent before the specimen breaks. Elongation at break is defined as the percentage (%) elongation of the agent relative to its original length.

As shown in Fig. 1 and 2, the relative elongation at break can be calculated using the curve of dependence of elongation on load. Fig. 1 and 2 show the study of 20-mm ring-shaped samples of hydrogel condoms made using the methods described in this document and containing polymer A or B, as indicated in the examples. The condom in Fig. 1 had a double wall thickness of 0.125 mm, a width of 58 mm, and the condom in Fig. 2 had a double wall thickness of 0.148 mm and a width of 53 mm.

According to an embodiment, the hydrogel agent has an elongation at break of about 200%, about 300%, about 400%, about 500%, about 600%, about 700%, about 800%, about 900%, about 1000%, about 1100%, about 1200%, about 1300%, about 1400%, about 1500%, about 1600%, about 1700%, about 1800%, about 1900%, or about 2000%.

According to an embodiment, the hydrogel is substantially impermeable to biological agents such as viruses or viral models (e.g., F-X174) or bacteria (e.g., Escherichia coli E. coli). F-X174 has an average diameter of about 30 nm; accordingly, the hydrogel is substantially impermeable to biological agents with an average diameter of 30 nm or more. According to an embodiment, the hydrogel is substantially impermeable to biological agents with an average diameter of 30 nm or more when a pressure of up to about 10 kPa is applied to the hydrogel. The pressure can be up to about 1 kPa, up to about 2 kPa, up to about 3 kPa, up to about 4 kPa, up to about 5 kPa, up to about 6 kPa, up to about 7 kPa, up to about 8 kPa, up to about 9 kPa, or up to about 10 kPa.

According to another embodiment, the hydrogel is permeable to low molecular weight compounds, such as water-soluble low molecular weight compounds. The inventors of the present invention have demonstrated that polyurethane hydrogels are permeable to sodium fluorescein (molecular weight 376.275 g/mol) and rhodamine B (molecular weight 479.02 g/mol). Accordingly, the hydrogel is permeable to water-soluble low molecular weight compounds whose molecular weight is about 500 g/mol or less.

One advantage of the polyurethane hydrogels described herein, for example when used in condoms, is that they are visually transparent, in contrast to traditional latex or polyisoprene condoms.

According to one embodiment, a condom made from a polyurethane hydrogel has a linear expansion of approximately 40%, a swelling agent content of approximately 60%, a tensile strength of approximately 15.2 MPa, a relative elongation at break of approximately 747%, an elastic modulus at 50% elongation of approximately 2.8 MPa, an elastic modulus at 100% elongation of approximately 3.6 MPa, and an elastic modulus at 300% elongation of approximately 6.7 MPa.

According to another embodiment, a condom made of polyurethane hydro

- 12 048599 gel, has a linear expansion of approximately 30%, a swelling agent content of approximately 50%, a tensile strength of approximately 26.3 MPa, a relative elongation at break of approximately 591%, a modulus of elasticity at 50% elongation of approximately 2.5 MPa, a modulus of elasticity at 100% elongation of approximately 3.3 MPa, and a modulus of elasticity at 300% elongation of approximately 6.6 MPa.

Condom testing may include inflating a condom with air to measure the volume of air that can be contained within the condom until it breaks. The volume of air that is contained within a condom when it breaks is known as the air volume at break. According to an exemplary embodiment of the hydrogel condoms described herein, the condom has an air volume at break of approximately 5 L to 40 L. For example, the air volume at break may be approximately 5 L, approximately 10 L, approximately 15 L, approximately 20 L, approximately 25 L, approximately 30 L, approximately 35 L, approximately 40 L, approximately 45 L, up to approximately 50 L.

In addition, when the condom is filled with air, the pressure also increases, and the maximum air pressure up to the rupture is known as the air pressure at rupture. According to an exemplary embodiment of the hydrogel condoms that are described herein, the condom has an air pressure at rupture that is from about 0.75 kPa to about 4 kPa. For example, the air pressure at rupture can be about 0.75 kPa, about 1 kPa, about 1.25 kPa, about 1.5 kPa, about 1.75 kPa, about 2 kPa, about 2.25 kPa, about 2.5 kPa, about 2.75 kPa, about 3 kPa, about 3.25 kPa, about 3.5 kPa, about 3.75 kPa, about 4 kPa, about 4.25 kPa, about 4.5 kPa, about 4.75 kPa or about 5 kPa. In some embodiments, the burst air pressure may be from about 1.3 kPa to about 3.6 kPa.

Polyurethane hydrogels have additional beneficial properties, including that users report that the polyurethane hydrogel agent feels like skin, feels moist, feels soft, feels in such a way that the user does not experience a loss of sensation (i.e., feels absent), or feels in a combination of ways. In some embodiments, the polyurethane hydrogels are visually transparent, such that visual appeal or visual stimulus is not lost.

In some embodiments, polyurethane hydrogels conduct heat more efficiently than other condom materials, such that body heat transfer is less disrupted.

In addition, polyurethane hydrogels cannot have an unfavorable odor or taste.

In some embodiments, polyurethane hydrogels are hypoallergenic, meaning they do not cause allergic reactions.

According to some embodiments, the polyurethane hydrogels are made in such a way that they contain a plurality of regions having different physical properties (e.g., elastic modulus, linear expansion, relative elongation at break, air pressure at break, etc.). This is achieved by using different polymers for each of the plurality of regions. For example, a condom can be made using a hydrogel having a higher elastic modulus on the inner surface, which can feel hard, and a hydrogel having a lower elastic modulus on the outer surface, which can feel soft, or vice versa. Alternatively or in addition, regions having different elastic moduli can be present, for example, the condom can include a tip region that differs in elastic modulus from the shaft, wherein the shaft can include regions or rings having different elastic moduli or other properties. By using polymers having different molecular weights and/or n and m number ratios, and by using the methods that are described herein, devices can be made that provide individual and different sensations for different aspects of the end use of the device; for example, a condom that provides a variety of sensations throughout the device and causes different sensations for each partner. In particular, hydrogels can feel like skin.

As presented in Table 1, the properties of the polyurethane hydrogel condoms described in this document are found to be favorable compared to the properties of traditional condoms.

- 13 048599

Table 1

Comparison of properties of typical condom materials and hydrogel

Condom material Relative elongation (%) Strength (MPa) Inflatable volume (l) Pressure (kPa) Latex 700-800 25-30 28-40 1.3-2.5 Polyisoprene 1036-1050 30.1-31.2 50-70 1.4-1.8 Polyurethane 443-449 38.4-40.2 5.5-13.5 3.5-14 Hydrogel 289-797 2.9-26.3 1-37 0.7-4.1

Examples

Example 1. Production of polyurethane solution.

The solvent contained ethanol and water, the ratio of which can range from 60:40 to 95:5, depending on the polyurethane. The ethanol:water ratio of 90:10 was chosen as the ratio at which the following polymers are readily soluble, including each of the polymers A-F below:

A: -CH2-(CH2-O-CH2) _n -CH2-[O-OCHN(C6H10)CH2(C6H10)NHCO-O-(CH2CH2-O-CH2CH2)-O-

OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH-(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -OOCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value of 5 and m is approximately 105-130; or

B: -CH2-(CH2-O-CH2)n-CH2-[O-OCHN(C6H10)CH2(C6H10)NHCO-O-(CH2CH2-O-CH2CH2)-O-

OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH-(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -OOCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value and is 4, and m is approximately 100-120;

C: -CH2-(CH2-O-CH2)n-CH2-[O-OCHN(C6H10)CH2(C6H10)NHCO-O-(CH2CH2-O-CH2CH2)-O-

OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH-(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -OOCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value and is 1.5, and m is approximately 10-20;

D: -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -[O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-(CH ₂ CH ₂ -O- CH ₂ CH ₂ )-O-

OCHN(C6Hio)CH2(C6Hio)NHCO-NH-(C6Hio)CH2(C6Hio)NHCO-0-CH2CH2-0-CH2CH2-0OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value and is 34, and m is approximately 75-85

E: -CH2-(CH2-O-CH2)n-CH2-[O-OCHN(C6H10)CH2(C6H10)NHCO-O-(CH2CH2-O-CH2CH2)-O-

OCHN(C6Hio)CH2(C6Hio)NHCO-NH-(C6Hio)CH2(C6Hio)NHCO-0-CH2CH2-0-CH2CH2-0OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value and is 30.5, and m is approximately 140-160.

F: -CH2-(CH2-O-CH2)n-CH2-[O-OCHN(C6H10)CH2(C6H10)NHCO-O-(CH2CH2-O-CH2CH2)-O-

OCHN(C6Hio)CH2(C6Hio)NHCO-NH-(C6Hio)cH2(C6Hio)NHCO-0-CH2CH2-0-CH2CH2-0OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -, where n is an average value and is 7, and m is approximately 200-240.

Polymer Solution: The polymers described above were individually dissolved using a solvent containing ethanol and water in a volume ratio of 90:10. The polymer concentration can range from 1% w/v up to 10% w/v for film formation. A concentration of 6% w/v was chosen for the preparation of all films (see Table 2). However, for the dip coating process, the concentration can be further optimized to control the film quality and the number of dips required to achieve the desired thickness.

The mixture is stirred overnight to solubilize the polymers. When heated to 70°C, the rate of solubilization increases.

The stress of the hydrogel prepared in the above examples was measured as a function of elongation using figure-eight shaped hydrogel samples at a stretching rate of 500 mm/min. The stress was calculated by determining the ratio of the force to the initial cross-sectional area of the figure-eight shaped sample. The relative elongation was determined as the ratio of the increased length to the initial length. The elastic modulus was calculated by determining the stress at sample elongations of 50%, 100%, and 300%.

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Table 2

Sample hydrogels and their approximate properties

A IN WITH D E F Compound, % Ethanol (v/v) 90 90 90 90 90 90 Water (vol./vol.) 10 10 10 10 10 10 A (w/v) 6 - - - In (w/v) - 6 - - C (w/v) - - 6 - D (w/v) - - - 6 E (w/v) 6 F (w/v) 6 Average molecular weight of the polymer Mw (kDa) 115 124 15 85 157 233 Range of elastic modulus Modulus of elasticity at 50% elongation (MPa) 1.9-2.3 3.4 - 4.0 11.9- 12.1 0.1 - 10.4 0.3 -9.1 0.5 -1.3 Modulus of elasticity at 100% elongation (MPa) 2.5-3.2 4.5 - 4.7 12.4- 12.6 0.3 - 10.5 0.6 - 9.9 0.8 - 1.7 Modulus of elasticity at 300% elongation (MPa) 4.2 - 4.5 6.3 - 7.5 13.6- 13.6 0.8 - 12.0 1.8 - 12.3 1.8-2.3

Example 2. Compatibility of swelling agent.

A series of personal care products were used to investigate one pathway for polymer swelling compatibility. Polymer sheets were made by pouring 5 mL of a 6% w/v polymer solution into a mold. The dried sheets were cut into samples and their lengths were measured. The polymers were then soaked in various swelling formulations that represented commercially available sexual and medical products. The polymers were soaked for 24 h in the swelling agent and remeasured to determine immediate swelling compared to controls and dry materials.

A variety of polymers were investigated, as well as lubricants of various types, including water-based, organosilicon-based, and oil-based compositions, which are presented in Table 3.

Linear expansion measurements of the hydrogels after swelling were conducted using a variety of personal care products. Examples for Polymer A and Polymer B are shown in Table 3. The tensile strength values were analyzed for each major type and the results demonstrated that the tensile strength was not reduced by any of the lubricant-based swelling agents. The results indicate that the hydrogel condoms exhibit a wider range of compatibility with a variety of lubricants than traditional latex or polyisoprene condoms, which cannot be used with oil-based lubricants because the oil degrades the condom agent. In addition, the hydrogels are compatible with silicone lubricants, which are not recommended for use with silicone toys.

- 15 048599

Types of Lubricating Agents

Table 3

Lubricating agent Basis Ingredients Linear extension Lubricant Durex KY Personal Water Water, glycerin, hydroxyethylcellulose, gluconolactone, methylparaben, sodium hydroxide, chlorhexidine digluconate Up to -45% Intimate gel Durex Naturals Water Water, glycerin, propanediol, xanthan gum, inulin, benzoic acid, alpha-glucan oligosaccharide, potassium lactate, lactic acid Up to -40% Lubricating agent Four Seasons Passion Water Purified water, glycerin, hydroxyethylcellulose, potassium sorbate, sodium benzoate, peppermint oil, sodium lactate, ethylenediaminetetraacetic acid (EDTA) Up to -45% Lubricating agent Four Seasons Pure Water Purified Water, Zemea Steareth-2, Xanthan Gum, Carrageenan, Sodium Benzoate, Potassium Sorbate, Vitamin E, Sodium Lactate Up to -45% Lifestyles Silky Lubricant Water Glycerin, deionized water, vegetable gum (methylcellulose), preservative Up to -25%

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smooth (phenoxyethanol) Microcyn Skin Care Water Electrolyzed water, sodium chloride (NaCl), sodium hypochlorite (NaOCl) and hypochlorous acid (HOC1) Up to -40% Hydrogel Epi soup Water MicroHeal® Superoxidized Solution, Polydimethylsiloxane Up to -40% Perfect glide Durex Organosilicon 100% organosilicon (cyclomethicone, dimethiconol) <5% Lifestyles Luxe Lubricant Organosilicon 100% organosilicon (cyclomethicone, dimethiconol) <5% Lubricant Jo Classic Hybrid Personal Water-organosilicon composite Propylene glycol, water, phenoxyethanol, dimethicone, cellulose gum, cyclopentasiloxane, sodium polyacrylate, trideceth-6, PEG/PPG-18/18, dimethicone Up to -45% Bonk Lube Personal Lubricating Agent Oil Sunflower Seed Oil (Helianthus Annuus), Jojoba Oil (Simmondsia Chinensis), White Beeswax (Cera Alba), Cocoa Seed Butter (Theobroma Cacao), Shea Butter (Butyrospermum Parkii) <5% YES OB Vegetable Oil Based Lubricant Oil Sunflower Seed Oil (Helianthus Annuus), Shea Butter (Butyrospermum Parkii), Sweet Almond Oil (Prunus Dulcis), White Honeycomb Wax (Cera Alba), Cocoa Seed Butter (Theobroma Cacao), Tocopherol (Vitamin E) <5%

Example 3. Production of experimental samples of condoms.

The dip coating process was used to make experimental condom samples, and for this purpose cylindrical molds were dipped into a heated polymer solution. The molds were preferably made of glass or metal. The inventors have found that plastic molds are not ideal for this purpose, as the polyurethane solution tends to coat the mold unevenly as a result of the dip.

In one experiment, multiple glass or metal molds were assembled in a mold making machine to produce multiple experimental condom samples.

The polymer solution was placed in a large container, the container being wide enough to contain the machine and the container being tall enough to accommodate the liquid being displaced. The container was placed underneath the machine.

The polymer solution in the container was heated to 25°C with continuous stirring. The molds were immersed in the polymer solution and removed at a speed of 20 to 200 mm/s, and the applied polymer solution after removal of the mold minimized the evaporation of the solvent.

The molds containing the polymer solution applied to them were kept at room temperature.

- 17 048599 temperature for at least 5 to 10 minutes until the solvent evaporates from the coating and a polyurethane film forms on the mold. This period can be significantly reduced if drying occurs at elevated temperatures, for example in an oven or dryer.

By repeating the dipping and drying process, the thickness of the polyurethane film increases, from which the condom is formed. To make condoms, polymers were typically dipped 1 to 6 times.

To make condoms, in some cases a series of dips was performed using a polymer of one molecular weight and a dip or series of dips using a polymer of a different molecular weight.

In one case, a condom was manufactured containing a first hydrogel layer containing polymer A and a second hydrogel layer containing polymer B. In another case, a condom was manufactured containing a first hydrogel layer containing polymer B and a second hydrogel layer containing polymer A.

When the solvent has completely evaporated from the coated molds, the mold-containing machine can be immersed in a container filled with an excess of swelling agent or hydrating solution to swell the dried film to form a hydrogel.

Example 4. Condom testing according to ISO standards.

The data presented below represent the results of standard, traditional international condom testing. The testing was conducted in accordance with ISO 23409:2011 Male condoms - Requirements and testing methods for condoms made from synthetic materials and ISO 4074:2015 Natural rubber latex male condoms - Requirements and testing methods for lot qualification of condoms. Tensile testing is not currently specified in ISO or ASTM protocols but provides useful guidance when developing alternative condom materials.

The condoms were manufactured using the selected polymers A and B presented above. The testing was carried out by En ersol using independent testing and quality assurance equipment accredited to ISO 17025:2017 and ISO 9001:2015, and included measurements of dimensional properties, tensile behaviour, inflation rupture and leakage.

To measure the length, the condom was stretched a small amount, ranging from 5 percent to 10 percent, to smooth out wrinkles caused by rolling and then suspended over a graduated core. The width was measured at right angles to the direction of the condom's length when it was unrolled and lying flat without any wrinkles. Typically, three thickness measurements were taken for each condom sample and the average value was determined. Table 4 presents the measurements for condoms designated as condom type A and condom type B; in each case, the condom type was determined according to the main component of the condom, which was the corresponding polymer type from Table 2.

Table 4

Condom measurement results

Thickness Small (mm) Average (mm) Large (mm) Condom type A 0,108 0,120 0,132 Condom type B 0,08 0,122 0,190 Width Small (mm) Average (mm) Large (mm) Condom type A 57 58.5 59 Condom type B 53 55.9 59

The tensile strength of condoms was investigated using a 20 mm wide specimen cut from the middle section of a condom. In the test, the specimen (ring) was stretched in cross-section until the agent ruptured, using a constant speed circular motion and applying pressure uniformly to the entire condom specimen. The test measured the force (breaking force in Newtons) required to break the agent; the length of the agent specimen at rupture (percent elongation, percentage increase from initial to final circumference); and the tensile breaking strength (in megapascals), with the agent thickness and breaking force in Newtons used in the calculations. Table 5 presents the tensile strength measurements for condoms containing polymer A or polymer B.

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Table 5

Tensile strength of condoms

Tensile strength Low (MPa) Average (MPa) High (MPa) Condom type A 2.9 8.6 15.2 Condom type B 3,4 10,5 26.3 Tearing force Small (N) Average(N) Large (L) Condom type A 6.8 20.7 35.5 Condom type B 7.2 25.6 77.7 Extension of agent Small (%) Average(%) Large (%) Condom type A 421 663 763 Condom type B 286 627 797

The burst pressure and air volume were investigated by inflating the condom like a balloon and measuring the air volume and air pressure required to burst it. The condom was unrolled and clamped to the stem, leaving approximately 150 mm for inflation. The apparatus used for the study inflates the condom by introducing clean, oil-free, moisture-free air into it at a specified rate. Table 6 presents the results of the air pressure measurements at burst for condoms containing polymer A or polymer B.

Table 6

Air pressure when condoms break

Pressure Low (kPa) Average (kPa) High (kPa) Condom type A 0,70 1,02 1.30 Condom type B 0.75 1.71 4.10 Volume Small (l) Medium (l) Large (l) Condom type A z,o 20.2 29,5 Condom type B 1,0 15,0 37,0

Leakage studies were conducted using the hanging method, in which the condom was filled with water, usually suspended vertically, and the observer observed leakage. In addition, the tip of the water-filled condom was tied and then rolled out on absorbent paper, observing the water on the paper. Studies were conducted using sample condoms from different lots and ensuring freedom from orifice (leakage) testing.

Additional condoms were made by layering different polymers. In one example, a condom made of polymer A was layered with polymer B, and vice versa. In these examples, the condoms exhibited different properties, as shown in Table 1. The condoms were tested for mechanical properties and met or exceeded ISO standards and the parameters observed in the mechanical test results above.

Example 5. Study of protection against bacteriophages.

Polymers A and B were tested for their biological protection properties and diffusion prevention of a small bacterial virus, bacteriophage F-X174, which was used as a stimulus particle. The use of F-X174 is known as a viral penetration test, which is typically used to test the protective properties of condoms (according to ISO 23409:2011). In these tests, a condom sample is fixed and the condom is filled with a suspension of the surrogate viral bacteriophage F-X174. When the sample is immersed in a collection fluid, the leakage of viral particles through the sample can be detected by analyzing the fluid for the presence of viral particles.

Hydrogel materials A and B were fixed between the sample chamber and the receiving chamber.

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Claims (28)

Franz diffusion cell. The receiving chamber was filled with phosphate-buffered saline (PBS), and the sample chamber was loaded with bacteriophage F-X174 in PBS. Samples were removed from the receiving chamber for analysis and bacteriophage quantification by plaque assay. Materials made defective by puncturing with a 25 G needle were used as positive controls. The test materials demonstrated impermeability to bacteriophage F-X174. In addition, studies were conducted using fixed and inflated condoms made of polymer A and polymer B. The condoms successfully passed the viral penetration study. In addition, hydrogels A and B were tested using E. coli bacteria, which cause urinary tract infections. Hydrogel materials A and B were fixed between the sample chamber and the receiving chamber of a Franz diffusion cell. The receiving chamber was filled with phosphate-buffered saline (PBS), and E. coli bacteria in PBS were loaded into the sample chamber. Samples were removed from the receiving chamber for analysis by growing on Luria-Bertani (LB) agar plates, and no growth of E. coli bacteria was detected in the samples removed from the receiving chamber. Materials made defective by puncturing with a 25 G needle were used as positive controls. The test materials demonstrated their impermeability to E. coli. Those skilled in the art will understand that numerous changes and/or modifications of the present invention, as presented in the specific embodiments, can be made without departing from the spirit and scope of the present invention as broadly described. Thus, the presented embodiments should be considered in all respects as illustrative and not restrictive. CLAUSE OF INVENTION 1. A method for producing a molded polyurethane hydrogel, the method comprising obtaining a first solution of at least one polyurethane having a molecular weight of 40,000 to 500,000 Daltons in a mixture of water and an organic polar solvent containing less than 40% v/v water; applying a layer of the first solution to the form; drying the layer of the first solution to form a polyurethane film on the form; and contacting the polyurethane film with a swelling agent under conditions such that the film forms a polyurethane hydrogel with a swelling agent content of from 1 to 95%, wherein the polyurethane comprises -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -[O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O(CH ₂ CH ₂ -O-CH ₂ CH ₂ )-O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH-(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -OCH ₂ CH ₂ -O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -O-CH ₂ )n-CH ₂ - and methyl and/or hydroxyl end groups, and wherein n is an average value independently selected to be any number from 1 to 35; and m is an average value independently selected to be any number from 15 to 500. 2. The method according to claim 1, wherein the molecular weight of the polyurethane is from 40,000 to 200,000 Daltons, from 150,000 to 350,000 Daltons, or from 300,000 to 500,000 Daltons. 3. The method according to claim 1 or 2, wherein the polyurethane is obtained by polymerizing 4,4'dicyclohexylmethane diisocyanate. 4. The method according to claim 1 or 2, wherein the polyurethane is a polyether-based polyurethane. 5. The method according to claim 4, wherein the polyether-based polyurethane is obtained by polymerizing 4,4'-dicyclohexylmethane diisocyanate and a polyether. 6. The method according to claim 5, wherein the polyether contains from 1 to 35 ethyl ether groups. 7. The method according to any one of claims 1 to 6, wherein the organic polar solvent is selected from the group consisting of ethanol, methanol, isopropanol, butanol, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, acetone, acetonitrile and any combination thereof. 8. The method according to claim 7, wherein the organic polar solvent is ethanol. 9. The method according to any one of claims 1 to 8, wherein the ratio of water to organic polar solvent is selected to be 5:95, 10:90, 15:85, 20:80, 25:75, 30:70, 35:65 or 40:60. 10. The method according to claim 9, wherein the ratio of water to organic polar solvent is 10:90. 11. The method according to any one of claims 1 to 10, wherein at least one agent is selected as the swelling agent, which is water, a glycol solution, a hydroxyethyl solution - 20 048599 cellulose, paraben-based solution, glycol-based solution, glycerol-based solution, oil-based solution or silicone-based solution. 12. The method of claim 11, wherein the swelling agent comprises one or more of a spermicidal agent, a lubricant, an antiviral agent, an antifungal agent, an antimicrobial agent, a prebiotic agent, a probiotic agent, a microbiome enhancer, a flavor additive, a fragrance additive, a sensation enhancing agent, a sterilizing agent, and a disinfectant. 13. The method according to any one of claims 1 to 12, wherein the polyurethane film is in contact with the swelling agent for at least one second at room temperature. 14. The method according to any one of claims 1 to 13, further comprising obtaining a second solution of at least one polyurethane having a molecular weight of from 40,000 to 200,000 Daltons, from 150,000 to 350,000 Daltons, or from 300,000 to 500,000 Daltons in a mixture of water and an organic polar solvent containing less than 40% v/v water; applying a layer of the second solution to the polyurethane film on the form; drying a layer of the second solution, whereby the layers form a polyurethane film on the form; and contacting the polyurethane film with a swelling agent under conditions such that the film forms a polyurethane hydrogel having a swelling agent content of from 1 to 95%, wherein the polyurethane comprises -CH ₂ -(CH ₂ -O-CH ₂ ) _n -CH ₂ -[OOCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-(CH ₂ CH ₂ -O-CH ₂ CH ₂ )-O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-NH(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -O-OCHN(C ₆ H ₁₀ )CH ₂ (C ₆ H ₁₀ )NHCO-O] _m -CH ₂ -(CH ₂ -OCH ₂ )n-CH ₂ -, where n is an average value that is independently selected from 1 to 35; and m is an average value that is independently selected from 15 to 500. 15. The method according to any one of claims 1 to 14, wherein the ratio of the numbers n and m is from 1:0.1 to 1:75. 16. The method according to claim 14 or 15, wherein at least one polyurethane in the second solution is not the same as at least one polyurethane in the first solution. 17. The method according to any one of claims 1 to 16, further comprising applying a subsequent layer of the first or second solution to the polyurethane film on the mold to increase the thickness or to create a particular feature of the polyurethane film. 18. The method according to any one of claims 1 to 17, further comprising applying a subsequent layer of the first or second solution to a portion of the polyurethane film on the mold to increase the thickness or to create a specific feature on the portion of the polyurethane film. 19. The method according to claim 18, wherein the specific feature formed by the subsequent layer has different modulus, tensile strength and/or linear expansion range values than the hydrogel formed from the layer to which it is applied. 20. The method according to any one of claims 14 to 19, wherein one or both of the molecular weight and the ratio of the numbers n and m of at least one polyurethane in the first solution differ from the molecular weight and the ratio of the numbers n and m of at least one polyurethane in the second solution. 21. The method according to any one of claims 14 to 20, wherein additional subsequent layers are applied to increase the thickness to a predetermined value. 22. The method according to any one of claims 1 to 21, wherein the molded polyurethane hydrogel has a linear expansion range of 1 to 100%. 23. The method according to any one of claims 1 to 22, wherein the molded polyurethane hydrogel has a tensile strength of from 1 MPa to 100 MPa, from 1 MPa to 20 MPa, from 20 MPa to 60 MPa, or from 60 MPa to 80 MPa. 24. The method according to any one of claims 1 to 23, wherein the molded polyurethane hydrogel has a relative elongation at break in the range from 200 to 2000%. 25. The method according to any one of claims 1 to 24, wherein the molded polyurethane hydrogel has at least one parameter from an elastic modulus at 50% elongation of 80 kPa to 15 MPa, an elastic modulus at 100% elongation of 200 kPa to 15 MPa, and an elastic modulus at 300% elongation of 700 kPa to 15 MPa. 26. A molded polyurethane hydrogel condom manufactured by the method according to any one of claims 1 to 25. 27. A molded polyurethane hydrogel condom, wherein the polyurethane hydrogel comprises polyurethane having a molecular weight of 40,000 to 500,000 Daltons and a swelling agent content of 40 to 70%. 28. A molded polyurethane hydrogel condom according to claim 27, having one or more parameters from the range of linear expansion from 1 to 100%, tensile strength from 1 MPa to 100 MPa, relative elongation at break in the range of 200 to 2000% and at least one parameter from an elastic modulus at 50% elongation from 80 kPa to 15 MPa, an elastic modulus at elongation -