CN114790274A - Waterborne polyurethane for condom and preparation method thereof - Google Patents
Waterborne polyurethane for condom and preparation method thereof Download PDFInfo
- Publication number
- CN114790274A CN114790274A CN202210367716.XA CN202210367716A CN114790274A CN 114790274 A CN114790274 A CN 114790274A CN 202210367716 A CN202210367716 A CN 202210367716A CN 114790274 A CN114790274 A CN 114790274A
- Authority
- CN
- China
- Prior art keywords
- parts
- component
- polyurethane
- waterborne polyurethane
- weight
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/08—Processes
- C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
- C08G18/12—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step using two or more compounds having active hydrogen in the first polymerisation step
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/34—Carboxylic acids; Esters thereof with monohydroxyl compounds
- C08G18/348—Hydroxycarboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/48—Polyethers
- C08G18/4804—Two or more polyethers of different physical or chemical nature
- C08G18/4808—Mixtures of two or more polyetherdiols
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/48—Polyethers
- C08G18/4833—Polyethers containing oxyethylene units
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/48—Polyethers
- C08G18/4854—Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
- C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
- C08G18/6666—Compounds of group C08G18/48 or C08G18/52
- C08G18/6692—Compounds of group C08G18/48 or C08G18/52 with compounds of group C08G18/34
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
- C09D175/04—Polyurethanes
- C09D175/08—Polyurethanes from polyethers
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Polyurethanes Or Polyureas (AREA)
Abstract
The invention discloses waterborne polyurethane for condoms and a preparation method thereof, wherein the preparation method mainly comprises the following steps: providing a first component consisting of an isocyanate monomer and a catalyst and a second component consisting of a polymer polyol, a hydrophilic monomer and a small molecule chain extender; slowly adding the first component and the second component into a reaction container, and stirring at high temperature for reaction to obtain a polyurethane prepolymer with ultrahigh molecular weight; and then after the system is cooled, adding a neutralizer for neutralization, and then adding water for homogenizing and emulsifying to obtain the stable waterborne polyurethane emulsion. The preparation method is simple in process, and the prepared waterborne polyurethane has the characteristics of super softness and high elasticity, and is very suitable for preparing condoms.
Description
Technical Field
The invention belongs to the technical field of high polymer materials, and particularly relates to a preparation method of waterborne polyurethane for condoms, and the waterborne polyurethane which is prepared by the preparation method, is used for condoms and has super-soft high elastic performance.
Background
Condoms are a non-pharmaceutical form of deterrence to conception and are the most common contraceptive tools used worldwide. The natural latex has the characteristics of high elongation at break, good rebound resilience, small creep and the like, and is a main raw material for manufacturing the traditional condom, however, the natural latex condom has a plurality of problems, such as: (1) the material strength is low, so that the condom is thicker (0.036mm is the thickness limit, although people select natural latex in a specific production area to prepare the condom with the thickness of 0.030mm, the natural latex in the specific production area has limited resources), the heat conductivity is low, and the use comfort is still required to be improved; (2) the failure to completely remove proteins that cause allergic reactions in humans; (3) in addition, recent studies have shown that natural latex condoms contain nitrosamines, which are strong carcinogens (mainly generated during vulcanization molding), and therefore are frequently used for a long time, and have the risk of inducing tumors.
Natural latex condoms have been increasingly replaced by polyurethane condoms due to the above-mentioned problems with natural latex condoms. The polyurethane is a copolymer with soft and hard segments, the soft segment enhances the elasticity of the polyurethane, and the hard segment increases the strength of the polyurethane. The condom made of the material adopts a solution film forming process, is compact in film and has good virus blocking capacity. Meanwhile, the strength of the polyurethane film is better than that of natural latex, and thinner condoms (the thickness can be 10-30 mu m) can be manufactured; and the thermal conductivity of the polyurethane material is better than that of natural latex, so that the comfort of a user is improved. However, polyurethane condoms also suffer from a relatively significant drawback: (1) the polyurethane has higher rigidity and smaller elongation (generally 500-650%), namely, the flexibility is greatly different from natural latex (the elongation of the natural latex is 1300-1500%), and the polyurethane is easy to slip in the using process, so that the using experience is reduced; (2) a large amount of organic solvent is used in the production process, which causes harm to the environment.
In order to make up for the defects of polyurethane condoms, waterborne polyurethane materials are produced. Compared with solvent type polyurethane, the waterborne polyurethane takes water as a dispersion medium, has the characteristics of no toxicity, no harm, economy, energy conservation, safety, reliability and the like, and is a green environment-friendly material. It has the advantages of low viscosity, high molecular weight, good applicability, etc., and has important applications in many industrial fields, such as materials for coatings, glass fibers, paper sizing, synthetic leather, biology, and films, etc.
The Chinese patent application with publication number CN106750079A discloses an aqueous polyurethane resin for condoms and a preparation method thereof, which is characterized in that a chain extender containing sulfonate is adopted, so that the condoms prepared by the method have high solid content and good sagging resistance, but the performance of the condoms prepared by the method is not disclosed.
The Chinese patent application with publication number CN107266645A discloses a siloxane modified waterborne polyurethane emulsion and a preparation method of a waterborne polyurethane condom, and is characterized in that 7.5-15% of hydroxyl-terminated polydimethylsiloxane is adopted as a soft segment of polyurethane in the formula in parts by weight, and the prepared polyurethane condom has the thickness of less than 0.03mm, the elongation at break of more than 1000%, the breaking strength of more than 30MPa and the 100% modulus of less than 2 MPa.
Although great progress has been made in the above polyurethane condoms, there is still a large gap in 100% modulus (flexibility) compared to natural latex condoms, such as: the 100% modulus of the existing polyurethane condom is mostly 1.5-2MPa, while the 100% modulus of natural latex is about 0.7 MPa. This indicates that the polyurethane condom is still far less flexible than a natural latex condom.
Disclosure of Invention
In view of the above, the invention needs to provide a preparation method of waterborne polyurethane for condoms, the preparation method is simple in process, and the prepared waterborne polyurethane has the characteristics of super softness and high elasticity and is very suitable for condoms.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a preparation method of waterborne polyurethane for condoms, which comprises the following steps:
providing a first component consisting of 25 to 30 parts by weight of an isocyanate monomer and 0.05 to 0.2 parts by weight of a catalyst;
providing a second component which consists of 60-70 parts by weight of polymer polyol, 1-2 parts by weight of hydrophilic monomer and 1-2 parts by weight of micromolecular chain extender after vacuum dehydration;
slowly adding the first component and the second component into a reaction container, and stirring and reacting at 80-90 ℃ to obtain a polyurethane prepolymer with ultrahigh molecular weight;
cooling the system to below 45 ℃, adding 2-3 parts by weight of neutralizing agent for neutralization, and then adding water for homogenizing and emulsification to obtain the stable waterborne polyurethane emulsion.
In a further embodiment, the isocyanate monomer is selected from the group consisting of dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and 4, 4' -diphenylmethane diisocyanate.
In a further scheme, the catalyst is selected from one of bismuth carboxylate mixture and dibutyltin dilaurate.
In a further aspect, the polymer polyol has a relative molecular mass of 2000-3000.
Further, the polymer polyol is selected from polytetrahydrofuran glycol, polytetramethylene ether glycol and polyethylene glycol or the combination of two of the polytetrahydrofuran glycol, the polytetramethylene ether glycol and the polyethylene glycol.
Further, the vacuum dehydration process specifically comprises the following steps: dehydrating the polymer polyol at 90-120 ℃ under vacuum for 2-3 h.
Further, the hydrophilic monomer is selected from one of dimethylol butyric acid and dimethylol propionic acid.
In a further scheme, the neutralizing agent is selected from one of triethylamine, N-diisopropylethylamine, triethanolamine and N, N-dimethylethanolamine.
Further, the small-molecule chain extender is selected from one of 1,3 propylene glycol, diethylene glycol, diethylaminoethanol and 2-methyl-1, 3 propylene glycol.
The invention further provides waterborne polyurethane for condoms, which is prepared by the preparation method.
Compared with the prior art, the invention has the following beneficial effects:
the invention makes isocyanate monomer and catalyst compose the first component, polymer polyol, hydrophilic monomer and chain extender compose the second component; and then slowly adding the first component and the second component into a reaction vessel, stirring for reaction, and controlling the reaction speed of the raw material components to ensure that the reaction is more smooth on one hand and to be beneficial to the formation of a hard segment structure of the waterborne polyurethane on the other hand, so that the waterborne polyurethane has a highly entangled fabric-shaped topological structure. When the long-chain highly entangled polyurethane is stretched, the tensile force is transmitted along the chain and is transmitted to many other chains through entanglement to dissipate elastic energy, so that the polyurethane is endowed with high toughness, and the rigidity-toughness conflict of the conventional polyurethane is solved, so that the polyurethane has the comprehensive performance of both super-softness and high elasticity. Unlike the polyurethane prepared by the conventional method, the polyurethane prepared by the invention has long chains, no chemical crosslinking points, plays a role of sliding linkage through entanglement of molecular chains, and has super-soft and high-elasticity performance.
The waterborne polyurethane prepared by the invention has ultrahigh molecular weight, the average molecular weight is between 100000-1000000, no chemical crosslinking exists, when a highly-entangled polyurethane long chain is stretched, the tension can be transmitted along the chain and transmitted to a plurality of other chains through entanglement to dissipate elastic energy, so that the waterborne polyurethane is endowed with high toughness, the conflict of rigidity-toughness of the conventional polyurethane is solved, and the waterborne polyurethane has the comprehensive properties of super-softness and high elasticity at the same time, and is very suitable for materials of condoms.
Drawings
FIG. 1 is a schematic diagram of a scheme for preparing waterborne polyurethane according to a preferred embodiment of the present invention;
FIG. 2 is a particle size distribution diagram of the aqueous polyurethane emulsion obtained in example 1 of the present invention.
Detailed Description
The embodiments of the present invention will be described in detail below, and the embodiments described below with reference to the drawings are exemplary only for the purpose of illustrating the present invention and are not to be construed as limiting the present invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
The first aspect of the present invention provides a method for preparing waterborne polyurethane, which can be combined with fig. 1, and mainly comprises the following steps:
s100, providing a first component and a second component.
Specifically, 25 to 30 parts by weight of isocyanate monomer and 0.05 to 0.2 part by weight of catalyst are uniformly mixed to form the first component, wherein conventional isocyanate monomer in the art can be adopted, preferably, the isocyanate monomer is selected from components with softer molecules and easier internal rotation, when the internal rotation barrier energy is lower, the internal rotation is less blocked, the conformational change is easier, and the flexibility is better, so that the flexibility of the waterborne polyurethane can be further improved, specific examples include but are not limited to dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, 4' -diphenylmethane diisocyanate, and the like, and the embodiment of the invention is selected from the combination of any two of the isocyanate monomers. The catalyst used herein may be any catalyst conventionally used in the art, and the function of the catalyst is mainly to reduce the activation energy required for the reaction to occur and to accelerate the reaction rate.
Further, the second component is composed of 60-70 parts by weight of polymer polyol after vacuum dehydration, 1-2 parts by weight of hydrophilic monomer and 1-2 parts by weight of micromolecular chain extender, the process for dehydrating the polymer polyol can be adjusted according to actual conditions, as long as the aim of dehydrating the polymer polyol can be achieved (generally, the water content is required to be lower than 0.2%), and specifically, in the embodiment of the invention, 60-70 parts of polymer polyol is dehydrated for 2-3 hours under the vacuum condition of 90-120 ℃, and is uniformly mixed with 1-2 parts of hydrophilic monomer and 1-2 parts of micromolecular chain extender after being cooled to 50-60 ℃ to form the second component. Wherein, according to the embodiment of the present invention, the polymer polyol can be selected by, but not limited to, one or two of polytetrahydrofuran glycol, polytetramethylene ether glycol and polyethylene glycol, preferably, the relative molecular mass of the polymer polyol is preferably 2000-3000, more preferably 2000, because if the polyether glycol with molecular weight of more than 3000 is selected, although the molecular weight is large, the softness and elongation of the emulsion can be increased, the emulsion state is unstable, and the subsequent steps are not easy to be performed; if the polyether glycol with the molecular weight lower than 2000 is selected, although the reaction activity of the polyether glycol and polyisocyanate is high, the free rotation space of a molecular chain of the small-molecular polyether is reduced due to too short chain segment length, so that the softness of the emulsion is greatly reduced, and the film-forming hardness is increased. Thus, in some embodiments of the invention, it is preferred that the polymer polyol have a relative molecular mass of 2000-3000. The hydrophilic monomer described herein contains a hydrophilic group, and is capable of providing an anionically stable aqueous emulsion effective for improving the hydrophilic property of polyurethane, and preferably one of dimethylolbutyric acid and dimethylolpropionic acid containing a carboxyl group and two primary hydroxyl groups as hydrophilic groups. In the examples according to the present invention, the small molecule chain extender described herein is selected from small molecule diols that are not easily formed into symmetry and crystallization, and the small molecule diols are diols having a molecular weight in the range of 50 to 300, and specific examples thereof include but are not limited to one of 1, 3-propanediol, diethylene glycol, diethylaminoethanol, 2-methyl-1, 3-propanediol; the micromolecule chain extender is matched with a hydrophilic monomer for chain extension, and the anion hydrophilic group and the nonionic hydrophilic group of the micromolecule chain extender have synergistic effect, so that the film forming permeability can be effectively improved, and the bonding fastness of the polyurethane emulsion and a base material is further improved. In addition, by adopting the specific micromolecular chain extender and the isocyanate monomer, flexible effective crosslinking can be introduced among polyurethane molecular chains, so that the comprehensive performance of the waterborne polyurethane can be obviously improved, and the rebound resilience of the waterborne polyurethane is not sacrificed.
S200, carrying out prepolymerization reaction step by step.
Specifically, the first component and the second component are slowly added into a reaction vessel (stirring is carried out while adding), and after the first component and the second component are added, the reaction is stirred at 80-90 ℃ to obtain the polyurethane prepolymer with ultrahigh molecular weight (the molecular weight is between 100000-1000000). The raw materials are respectively formed into a first component and a second component, and the first component and the second component are subjected to a gradual prepolymerization reaction in a slow adding mode, particularly, on one hand, the reaction can be carried out more smoothly; on the other hand, the method is beneficial to the formation of a hard segment structure of the waterborne polyurethane, so that the waterborne polyurethane has a highly entangled fabric-like topological structure, when the long chains of the highly entangled polyurethane are stretched, tension is transmitted along the chains and is transmitted to a plurality of other chains through entanglement to dissipate elastic energy, so that the polyurethane is endowed with high toughness, the rigidity-toughness conflict of the conventional polyurethane is solved, and the waterborne polyurethane has the comprehensive performance of super-softness and high elasticity. It should be noted that, in order to ensure the flexibility of the aqueous polyurethane while ensuring the reaction rate, the slow and preferable control of the dropping speed is 5 to 10mL/min, and the specific adding manner is not particularly limited, and may be a dropping or injecting manner, preferably an injecting manner, which is conventional in the art, so as to facilitate the control. Further, in some embodiments of the invention, the stirring rate is preferably 150-300 r/min. In the step, the molecular weight of the polyurethane prepolymer can be controlled by controlling the temperature, the stirring rate, the component adding rate, the reaction time and the like.
S300, neutralizing and emulsifying.
Specifically, the polyurethane prepolymer is cooled to below 45 ℃, added with 2-3 parts by weight of neutralizing agent for neutralization, and then added with water for homogeneous emulsification to obtain stable aqueous polyurethane emulsion. Neutralizing the hydrophilic monomer by adding neutralizing agent, and adding water for homogenizing and emulsifying, wherein the parameter of homogenizing and emulsifying is not limited, and can be adjusted according to the actual situation, preferably emulsifying for 30 + -10 min under 2000 + -500 r/min, more preferably emulsifying for 30min under 2000 r/min.
In a second aspect, the invention provides a waterborne polyurethane for condoms, which is prepared by the preparation method according to the first aspect.
The present invention is illustrated below by specific examples, which are provided for illustrative purposes only and do not limit the scope of the present invention in any way, and in addition, unless otherwise specified, conditions or steps are not described in detail and the methods are conventional, and reagents and materials used are commercially available. Unless otherwise specified, "parts", etc. described in the following examples and comparative examples are parts by weight, and the relative molecular masses of the polymer polyols used in the following examples 1 to 6 are all 2000.
Example 1
Mixing 8 parts of dicyclohexylmethane diisocyanate, 22 parts of hexamethylene diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
24 parts of polyethylene glycol and 40 parts of polytetramethylene ether glycol are dehydrated for 2 hours under the condition of 120 ℃, and are mixed with 1 part of dimethylolbutyric acid and 2 parts of diethylene glycol to form a second component after being cooled to 50 ℃;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min respectively, stirring simultaneously, and stirring and reacting for 3 hours at 90 ℃ after injection is finished to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
FIG. 2 shows the particle size distribution of the aqueous polyurethane emulsion of this example, and it can be seen that the particle size of the aqueous polyurethane is relatively uniform, and the average particle size is about 126 nm.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good rebound resilience, the 100% modulus at definite elongation is 0.6MPa, and the elastic recovery rate is close to 100% when the polyurethane is stretched by 600%.
Example 2
Mixing 22 parts of dicyclohexylmethane diisocyanate, 8 parts of hexamethylene diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
dehydrating 24 parts of polytetramethylene ether glycol and 40 parts of polyethylene glycol at 120 ℃ for 2 hours in vacuum, and forming a second component with 1 part of dimethylolpropionic acid and 2 parts of 2 methyl 1,3 propanediol after cooling to 50 ℃;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at the temperature of 90 ℃ for reacting for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 900000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolpropionic acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and has good resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.7MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 3
Mixing 22 parts of 4, 4' -diphenylmethane diisocyanate, 8 parts of hexamethylene diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
vacuum dehydrating 24 parts of polytetrahydrofuran glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2h, and mixing with 1 part of dimethylolbutyric acid and 2 parts of 1, 3-propylene glycol after cooling to 50 ℃ to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at the temperature of 90 ℃ for reacting for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 800000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good rebound resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.8MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 4
Mixing 8 parts of 4, 4' -diphenylmethane diisocyanate, 22 parts of hexamethylene diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
vacuum dehydrating 24 parts of polytetrahydrofuran glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2h, cooling to 50 ℃, and mixing with 1 part of dimethylolbutyric acid and 2 parts of 2-methyl-1, 3-propanediol to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at the temperature of 90 ℃ for reaction for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 800000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.8MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 5
Mixing 8 parts of 4, 4' -diphenylmethane diisocyanate, 22 parts of cyclohexylmethane diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
dehydrating 24 parts of polyethylene glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2 hours in vacuum, and mixing with 1 part of dimethylolbutyric acid and 2 parts of 1, 3-propylene glycol to form a second component after the temperature is reduced to 50 ℃;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at the temperature of 90 ℃ for reacting for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 800000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.8MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 6
Mixing 8 parts of cyclohexylmethane diisocyanate, 22 parts of 4, 4' -diphenylmethane diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
vacuum dehydrating 24 parts of polytetrahydrofuran glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2h, cooling to 50 ℃, and mixing with 1 part of dimethylolbutyric acid and 2 parts of 2-methyl-1, 3-propanediol to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at the temperature of 90 ℃ for reacting for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 800000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good rebound resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.9MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 7
Mixing 10 parts of dicyclohexylmethane diisocyanate, 15 parts of hexamethylene diisocyanate, 0.05 part of bismuth isooctanoate and 0.05 part of bismuth neodecanoate to form a first component;
vacuum dehydrating 30 parts of polyethylene glycol (molecular weight of 2500) and 30 parts of polytetramethylene ether glycol (molecular weight of 2500) at 90 deg.C for 3h, cooling to 50 deg.C, and mixing with 1.5 parts of dimethylolbutyric acid and 1.5 parts of 1, 3-propanediol to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 150r/min according to 8mL/min, stirring simultaneously, and stirring and reacting for 4 hours at 80 ℃ after injection is finished to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 2 parts of triethanolamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 20min at the condition of 2500r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.7MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Example 8
Mixing 14 parts of 4, 4' -diphenylmethane diisocyanate, 14 parts of hexamethylene diisocyanate and 0.2 part of catalyst dibutyltin dilaurate to form a first component;
dehydrating 25 parts of polytetrahydrofuran glycol (molecular weight is 3000) and 45 parts of polytetramethylene ether glycol (molecular weight is 3000) under vacuum at 100 ℃ for 2.5h, cooling to 50 ℃, and mixing with 2 parts of dimethylolpropionic acid and 2 parts of 2 methyl 1, 3-propanediol to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 300r/min according to 10mL/min respectively, stirring simultaneously, and stirring and reacting for 3 hours at 85 ℃ after injection is finished to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 2.5 parts of N, N-diisopropylethylamine to neutralize dimethylolpropionic acid, then adding water into the reactor, and homogenizing and emulsifying for 40min under the condition of 1500r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has the characteristics of super softness and high elasticity, and particularly has good resilience, the 100% definite modulus of elasticity of the waterborne polyurethane is 0.7MPa, and the elastic recovery rate of the waterborne polyurethane approaches 100% when the waterborne polyurethane is stretched by 600%.
Comparative example 1
Mixing 8 parts of dicyclohexylmethane diisocyanate, 22 parts of isophorone diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
vacuum dehydrating 24 parts of polyethylene glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2 hours, and mixing with 1 part of dimethylolbutyric acid and 2 parts of diethylene glycol to form a second component after cooling to 50 ℃;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at 90 ℃ for reaction for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The waterborne polyurethane prepared in the embodiment has lower resilience, the 100% definite elongation modulus of the waterborne polyurethane is 1.5MPa, and the recovery rate of the elasticity is close to 100% when the waterborne polyurethane is stretched by 400%.
Comparative example 2
Mixing 8 parts of dicyclohexylmethane diisocyanate, 22 parts of hexamethylene diisocyanate and 0.05 part of catalyst dibutyltin dilaurate to form a first component;
vacuum dehydrating 24 parts of polyethylene glycol (molecular weight 1000) and 40 parts of polytetramethylene ether glycol (molecular weight 1000) at 120 ℃ for 2h, cooling to 50 ℃, and mixing with 1 part of dimethylolbutyric acid and 2 parts of diethylene glycol to form a second component;
injecting the first component and the second component into a reactor with the rotating speed of 200r/min according to 5mL/min, and stirring the first component and the second component in the reactor at 90 ℃ for reaction for 3 hours to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and homogenizing and emulsifying for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The aqueous polyurethane prepared in the comparative example has lower resilience, the 100% modulus at definite elongation is 1.6MPa, and the elastic recovery rate is only close to 100% when the polyurethane is stretched by 400%.
Comparative example 3
The composition of the raw materials in this comparative example is the same as that in example 1, except that: the preparation process is different. The specific preparation method of this comparative example is as follows:
vacuum dehydrating 24 parts of polyethylene glycol and 40 parts of polytetramethylene ether glycol at 120 ℃ for 2h, cooling to 50 ℃, adding 8 parts of dicyclohexylmethane diisocyanate and 22 parts of hexamethylene diisocyanate, adding 0.05 part of dibutyltin dilaurate serving as a catalyst, heating to 90 ℃, and stirring in a reactor at the rotating speed of 200r/min for reacting for 2 h; cooling to 50 ℃, adding 1 part of dimethylolbutyric acid and 2 parts of diglycol, and continuing to react for 1 hour to generate a polyurethane prepolymer with the average molecular weight of 1000000;
then cooling to below 45 ℃, adding 3 parts of triethylamine to neutralize dimethylolbutyric acid, then adding water into the reactor, and stirring at high speed for 30min under the condition of 2000r/min to form stable waterborne polyurethane emulsion.
The aqueous polyurethane prepared in the comparative example has lower rebound resilience, the 100% modulus at definite elongation is 1.4MPa, and the elastic recovery rate is only close to 100% when the polyurethane is stretched by 400%.
Test example
The aqueous polyurethanes prepared in examples 1 to 8 and comparative examples 1 to 3 were prepared into polyurethane condoms, and the performance of the prepared condoms was measured according to GB7544-1992, GB/T7546-1992 and GB/T7547-1992, and the test results are shown in Table 1 below.
The preparation process of the waterborne polyurethane condom can be referred to a preparation method of the waterborne polyurethane condom disclosed in CN103640133A, and specifically comprises the following steps: cleaning and drying a stainless steel mould, immersing the mould into nano-scale waterborne polyurethane cross-linked particle emulsion, taking out the nano-scale waterborne polyurethane cross-linked particle emulsion, dripping the glue, drying, immersing the treated mould into the waterborne polyurethane emulsion, taking out the waterborne polyurethane emulsion, drying, obtaining a waterborne polyurethane adhesive film on the surface of the mould, curling the open end of the waterborne polyurethane adhesive film on the surface of the mould, immersing the treated mould into hot water at the temperature of 50 +/-5 ℃, drying after immersing, immersing into a release agent, taking out, drying, performing electric inspection by adopting a dry method, performing electric inspection on the treated adhesive film, and demolding after the electric inspection is qualified, thus obtaining the polyurethane condom.
TABLE 1 condom Performance test results
As can be seen from the test results in Table 1, the thickness of the polyurethane condom prepared by the preparation process of the invention is as low as below 0.015mm, and the strength is more than twice as high as that of the latex condom (the latex is generally 10-15 MPa); and it can be seen that the higher the molecular weight of the waterborne polyurethane, the closer the 100% modulus (flexibility) of the resulting polyurethane condom to, and even beyond, the performance of a latex condom (about 0.7 MPa). Therefore, the super-soft high-elasticity waterborne polyurethane prepared by the invention not only keeps the characteristics of ultra-thinness and high strength of the polyurethane condom, but also has the flexibility superior to that of the latex condom, and has simple process and excellent comprehensive performance.
As can be seen from the comparison of the test results of comparative example 1 and example 1, the flexibility of comparative example 1 is inferior to that of example 1, which shows that the combination of hexamethylene diisocyanate with softer isocyanate-selective molecules and easier internal rotation can produce more excellent comprehensive performance of the waterborne polyurethane; in the comparative example 1, the adopted isophorone diisocyanate has cis-form and trans-form asymmetric structures, so that intermolecular repulsion can be increased, steric hindrance can be formed, polyurethane forms a cross-linked network structure, the film-forming hardness of the product can be increased, and the flexibility is poor.
From the test results of comparative example 2 and example 1, it can be seen that comparative example 2 is also less flexible than example 1, indicating that the combination of polyether diols having a molecular weight of 2000 gives waterborne polyurethanes having superior overall properties; in comparative example 2, polyether glycol with a molecular weight of 1000 is used as the soft segment of polyurethane, and although the reaction activity of the polyether glycol with polyisocyanate is high, the free rotation space of a molecular chain of small-molecular polyether is reduced due to too short segment length, so that the softness of the emulsion is greatly reduced, and the film forming hardness is increased.
As can be seen from the test results of comparative example 3 and example 1, comparative example 3 is not as flexible as example 1, which shows that the waterborne polyurethane obtained by controlling the raw materials to gradually undergo prepolymerization reaction in a slow mixing manner after forming the first component and the second component respectively has good flexibility and elasticity, and has more excellent comprehensive properties.
All possible combinations of the technical features of the above embodiments may not be described for the sake of brevity, but should be considered as within the scope of the present disclosure as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is specific and detailed, but not to be understood as limiting the scope of the invention. It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A preparation method of waterborne polyurethane for condoms is characterized by comprising the following steps:
providing a first component consisting of 25 to 30 parts by weight of an isocyanate monomer and 0.05 to 0.2 parts by weight of a catalyst;
providing a second component, wherein the second component consists of 60-70 parts by weight of polymer polyol, 1-2 parts by weight of hydrophilic monomer and 1-2 parts by weight of micromolecular chain extender after vacuum dehydration;
slowly adding the first component and the second component into a reaction container, and stirring and reacting at 80-90 ℃ to obtain a polyurethane prepolymer with ultrahigh molecular weight;
cooling the system to below 45 ℃, adding 2-3 parts by weight of neutralizing agent for neutralization, and then adding water for homogenizing and emulsification to obtain the stable waterborne polyurethane emulsion.
2. The method of claim 1, wherein the isocyanate monomer is selected from the group consisting of dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and 4, 4' -diphenylmethane diisocyanate.
3. The method of claim 1, wherein the catalyst is selected from the group consisting of a bismuth carboxylate mixture and dibutyltin dilaurate.
4. The method of claim 1, wherein the polymer polyol has a relative molecular mass of 2000-3000.
5. The method according to claim 1, wherein the polymer polyol is one or two selected from polytetrahydrofuran glycol, polytetramethylene ether glycol and polyethylene glycol.
6. The preparation method according to claim 1, wherein the vacuum dehydration process comprises: dehydrating the polymer polyol at 90-120 ℃ under vacuum for 2-3 h.
7. The method of claim 1, wherein the hydrophilic monomer is selected from the group consisting of dimethylolbutyric acid and dimethylolpropionic acid.
8. The method of claim 1, wherein the neutralizing agent is one selected from the group consisting of triethylamine, N-diisopropylethylamine, triethanolamine, and N, N-dimethylethanolamine.
9. The method of claim 1, wherein the small chain extender is selected from the group consisting of 1,3 propylene glycol, diethylene glycol, diethylaminoethanol, and 2 methyl 1,3 propylene glycol.
10. An aqueous polyurethane for condoms, characterised in that it is produced by a process according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210367716.XA CN114790274A (en) | 2022-04-08 | 2022-04-08 | Waterborne polyurethane for condom and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210367716.XA CN114790274A (en) | 2022-04-08 | 2022-04-08 | Waterborne polyurethane for condom and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114790274A true CN114790274A (en) | 2022-07-26 |
Family
ID=82461404
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210367716.XA Pending CN114790274A (en) | 2022-04-08 | 2022-04-08 | Waterborne polyurethane for condom and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114790274A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6017997A (en) * | 1997-10-31 | 2000-01-25 | The B. F. Goodrich Company | Waterborne polyurethane having film properties comparable to rubber |
| US6451908B1 (en) * | 1999-04-14 | 2002-09-17 | The Dow Chemical Company | Polyurethane films prepared from polyurethane dispersions |
| CN103640133A (en) * | 2013-12-10 | 2014-03-19 | 上海强睿博化工有限公司 | Method for preparing universal or composite waterborne polyurethane condom |
| JP2015101625A (en) * | 2013-11-22 | 2015-06-04 | トーヨーポリマー株式会社 | Polyurethane aqueous dispersion, and film molded article and glove obtained from the same |
| CN106750079A (en) * | 2016-12-23 | 2017-05-31 | 安庆市德诚化工有限公司 | A kind of waterborne polyurethane resin for sheath and preparation method thereof |
| CN109160996A (en) * | 2018-08-22 | 2019-01-08 | 四川大学 | A kind of aqueous emulsion of polyurethane, condom and preparation method thereof |
| CN111138614A (en) * | 2019-12-19 | 2020-05-12 | 合肥科天水性科技有限责任公司 | Waterborne polyurethane emulsion for low-modulus high-strength ultrathin polyurethane condom and preparation method thereof |
-
2022
- 2022-04-08 CN CN202210367716.XA patent/CN114790274A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6017997A (en) * | 1997-10-31 | 2000-01-25 | The B. F. Goodrich Company | Waterborne polyurethane having film properties comparable to rubber |
| US6451908B1 (en) * | 1999-04-14 | 2002-09-17 | The Dow Chemical Company | Polyurethane films prepared from polyurethane dispersions |
| JP2015101625A (en) * | 2013-11-22 | 2015-06-04 | トーヨーポリマー株式会社 | Polyurethane aqueous dispersion, and film molded article and glove obtained from the same |
| CN103640133A (en) * | 2013-12-10 | 2014-03-19 | 上海强睿博化工有限公司 | Method for preparing universal or composite waterborne polyurethane condom |
| CN106750079A (en) * | 2016-12-23 | 2017-05-31 | 安庆市德诚化工有限公司 | A kind of waterborne polyurethane resin for sheath and preparation method thereof |
| CN109160996A (en) * | 2018-08-22 | 2019-01-08 | 四川大学 | A kind of aqueous emulsion of polyurethane, condom and preparation method thereof |
| CN111138614A (en) * | 2019-12-19 | 2020-05-12 | 合肥科天水性科技有限责任公司 | Waterborne polyurethane emulsion for low-modulus high-strength ultrathin polyurethane condom and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 橡胶工业原材料与装备简明手册编审委员会: "《橡胶工业原材料与装备简明手册 原材料与工艺耗材分册》", 北京理工大学出版社, pages: 271 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107266645B (en) | Siloxane modified waterborne polyurethane emulsion and preparation method of waterborne polyurethane condom | |
| CA1037192A (en) | Non-ionic polyurethane dispersions | |
| CN112079986B (en) | Waterborne polyurethane emulsion and preparation method and application thereof | |
| CN111808260B (en) | Thermosensitive condom based on waterborne polyurethane and preparation method thereof | |
| CN108503783B (en) | Thermoplastic polyurethane elastomer and preparation method thereof | |
| CN110105525B (en) | NDI-based polyurethane microporous elastomer resistant to damp-heat aging and preparation method thereof | |
| CN109160996B (en) | Polyurethane aqueous emulsion, condom and preparation method thereof | |
| JPS60156456A (en) | Production of polyurethane condome | |
| CN109912766B (en) | Waterborne self-extinction acrylic ester modified polyurethane resin and preparation method thereof | |
| CN111138614A (en) | Waterborne polyurethane emulsion for low-modulus high-strength ultrathin polyurethane condom and preparation method thereof | |
| CN109160990B (en) | Alkyl side chain modified polyurethane aqueous emulsion, preparation method thereof and application thereof in polyurethane condom | |
| JPH06316616A (en) | Aqueous dispersion of fluorinated polyurethane | |
| CN109734875A (en) | A kind of aminosilane coupling agent modifying aqueous polyurethane and preparation method thereof | |
| US3635907A (en) | Process for the production of polyurethanes | |
| KR101978113B1 (en) | Method for manufacturing polyurethane compression sponge with water-repellent surface and polyurethane compression sponge by manufactured thereof | |
| CN114790274A (en) | Waterborne polyurethane for condom and preparation method thereof | |
| JPH1181046A (en) | Water-absorbing polyurethane yarn and its production | |
| CN113956522B (en) | Preparation method of high-strength polyurethane product | |
| CN115260443A (en) | Waterborne polyurethane material and preparation method of waterborne polyurethane material applied to gloves | |
| CN113527620A (en) | Non-ionic aqueous polyurethane gel and preparation method thereof | |
| CN112079982B (en) | Super-soft protein-imitated hydrolysis-resistant polyurethane resin and preparation method thereof | |
| JP2023541693A (en) | High burst volume aqueous polyurethane condom and method for its preparation | |
| JPH0618919B2 (en) | Porous sheet and its use | |
| Du et al. | Preparation and properties of waterborne polyurethane adhesives modified by polystyrene | |
| CN112574383B (en) | Waterborne polyurethane emulsion and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |