Waterborne polyurethane for medical gloves as well as preparation method and application of waterborne polyurethane

Abstract

The invention provides waterborne polyurethane for medical gloves as well as a preparation method and application of the waterborne polyurethane, and belongs to the technical field of medical materials. The preparation method comprises the following steps: uniformly mixing 35-40 parts of polyurethane A, 14-18 parts of polyurethane B, 8-12 parts of a surfactant, 7-11 parts of a modified filler, 2-5 parts of caprolactam and 70-75 parts of deionized water, and carrying out ultrasonic treatment for 15-20 minutes to obtain the waterborne polyurethane for the medical gloves. The waterborne polyurethane disclosed by the invention is high in storage stability, good in mechanical property and excellent in radiation resistance and solvent resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of medical materials, and particularly relates to water-based polyurethane for medical gloves and a preparation method and application thereof. Background Art

[0002] Medical gloves are usually made of materials such as latex, nitrile rubber or polyvinyl chloride, but in recent years, water-based polyurethane has gradually become a new choice due to its environmental and performance advantages. The application of water-based polyurethane in medical gloves has many advantages, including environmental protection, good mechanical properties and comfort.

[0003] When using water-based polyurethane to prepare medical gloves, there are some technical problems that need to be solved. These problems mainly focus on the mechanical properties, chemical properties, biocompatibility and comfort of the gloves: (1) Water-based polyurethane may exhibit lower tensile strength and elongation at break when preparing medical gloves, affecting the durability and comfort of the gloves. (2) Medical gloves may encounter problems of tearing and wear during use, affecting their service life. (3) Water-based polyurethane gloves may perform poorly in terms of waterproofness and chemical resistance, especially when exposed to certain organic solvents. (4) Water-based polyurethane gloves may have skin irritation and allergic reaction problems, affecting the health of users. (5) The comfort of the gloves directly affects the user experience, and there may be problems with poor touch or insufficient breathability.

[0004] In order to improve the comfort of waterborne polyurethane in the preparation of medical gloves, the prior art adjusts the polyurethane formula, such as increasing the proportion of hard segments or using high-performance isocyanates and polyols, to improve the tensile strength and elongation at break of the material. However, although increasing the proportion of hard segments can improve the tensile strength and elongation at break, it may also affect other properties of the material, such as solvent resistance and radiation resistance.

[0005] Therefore, there is an urgent need for a water-based polyurethane for medical gloves with excellent comprehensive performance. Summary of the invention

[0006] The invention aims to provide an aqueous polyurethane for medical gloves and a preparation method and application thereof.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A water-based polyurethane for medical gloves, comprising the following components in parts by weight: 35-40 parts of polyurethane A, 14-18 parts of polyurethane B, 8-12 parts of surfactant, 7-11 parts of modified filler, 2-5 parts of caprolactam and 70-75 parts of deionized water;

[0009] The preparation method of polyurethane A comprises the following steps: by weight,

[0010] (1) Mix 0.3-0.5 parts of double-terminal hydroxyl polyether modified silicone oil, 15-20 parts of polyether polyol, 5-8 parts of dimethylol propionic acid, and 4-6 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol, stir and heat to 94-98°C, vacuum dehydrate, cool to 25-30°C, add 45-50 parts of diisocyanate, stir and heat to 80-85°C, and keep warm for 2-3 hours , cool to 50-55°C, continue to add 50-55 parts of acetone, stir and heat to 74-76°C for reaction for 7-9h, then cool to 15-20°C, add 3.0-3.5 parts of triethylamine and 200-220 parts of acetone, stir for 40-50min to obtain prepolymer A; the diisocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate;

[0011] (2) Under stirring conditions of 1200-1400 r / min, 450-460 parts of an ice-water mixture are added to prepolymer A, stirred for 10-15 min, and then the speed is adjusted to 500-600 r / min, and a solution consisting of 2-2.5 parts of ethylenediamine and 10-12 parts of water is added, and stirring is continued for 4-5 h to obtain emulsion A;

[0012] (3) The emulsion A is heated to 40-45°C, and the acetone is removed to obtain polyurethane A.

[0013] Furthermore, the polyether polyol includes a polyether diol having a hydroxyl number of 36-39 mgKOH / g, a polyether triol having a hydroxyl number of 535 mgKOH / g, and a polyether diol having a hydroxyl number of 153-188 mgKOH / g in a weight ratio of (1.3-1.5):(0.2-0.5):1.

[0014] In order to ensure that medical gloves are not easily damaged during stretching, the water-based polyurethane used to prepare medical gloves requires a higher tensile strength, and the tensile strength of water-based polyurethane in the prior art is not ideal. The present invention uses double-terminal hydroxyl polyether modified silicone oil to prepare polyurethane A, which can improve the tensile strength of water-based polyurethane used for medical gloves. Double-terminal hydroxyl polyether modified silicone oil has good flexibility, which can improve the flexibility of polyurethane, making it difficult to break during stretching, and the hydroxyl functional groups at both ends can react with the isocyanate groups in the polyurethane matrix to enhance the interfacial bonding force. However, the elongation at break of water-based polyurethane is not ideal.

[0015] Further, the preparation method of polyurethane B comprises the following steps, measured by weight:

[0016] (1) 15-20 parts of polyester polyol, 5-8 parts of dimethylol propionic acid, and 4-6 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol are mixed, heated to 94-98° C. with stirring, vacuum dehydrated at -0.1 MPa for 2-3 hours, cooled to 25-30° C., 45-50 parts of isophorone diisocyanate are added, heated to 80-85° C. with stirring, kept warm for reaction for 2-3 hours, cooled to 50-55° C., 50-55 parts of acetone are added, heated to 74-76° C. with stirring, reacted for 7-9 hours, then cooled to 15-20° C., 3.0-3.5 parts of triethylamine and 200-220 parts of acetone are added, and stirred for 40-50 minutes to obtain prepolymer B;

[0017] (2) Under stirring conditions of 1200-1400 r / min, 450-460 parts of an ice-water mixture are added to prepolymer B, stirred for 10-15 min, and then the rotation speed is adjusted to 500-600 r / min, and a solution consisting of 2-2.5 parts of ethylenediamine and 10-12 parts of water is added, and stirring is continued for 4-5 h to obtain emulsion B;

[0018] (3) The emulsion B is heated to 40-45°C and acetone is removed under -0.09 MPa to obtain polyurethane B.

[0019] Furthermore, the polyester polyol includes polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g, and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g in a weight ratio of (1.2-1.4):1:(0.3-0.5).

[0020] In order to improve the elongation at break of waterborne polyurethane, the present invention compounded polyurethane A prepared from polyether polyol and polyurethane B prepared from polyester polyol to improve the elongation at break of waterborne polyurethane. Under this condition, the puncture strength of waterborne polyurethane used in medical gloves was also improved.

[0021] Medical gloves are generally sterilized by irradiation, but it is easy to cause aging of the gloves, resulting in performance degradation. In the system of the present invention, when polyether polyols composed of a specific ratio and polyester polyols composed of a specific ratio are used to prepare polyurethane A and polyurethane B respectively, the tensile strength and elongation at break of the water-based polyurethane after irradiation can be improved. This is mainly because polyether polyols composed of a specific ratio and polyester polyols composed of a specific ratio are used to prepare polyurethane A and polyurethane B respectively. After mixing, they can interact with each other during the stretching process to disperse stress and prevent stress concentration, thereby improving elongation at break. Polyester polyols provide strength and polyether polyols provide flexibility. The combination of the two can achieve a balance between strength and flexibility. The appropriate proportion of polyether polyols and polyester polyols can promote the complexity of the cross-linked network system in the material and improve its stability under irradiation conditions.

[0022] Furthermore, the surfactant is Tween 60, nonylphenol polyoxyethylene ether (Shandong Xiaoqing New Chemical Co., Ltd., model NP-40) and disodium octadecyl succinamide sulfonate (CAS: 14481-60-8) in a weight ratio of 1: (1.2-1.5): (0.5-0.8).

[0023] In the present invention, adding polyurethane A and polyurethane B simultaneously will result in poor storage stability of the waterborne polyurethane. By using a specific surfactant, the stability of the waterborne polyurethane can be improved.

[0024] Furthermore, the preparation method of the modified filler comprises the following steps:

[0025] (1) mixing nano calcium carbonate, nano zinc oxide and nano silicon dioxide to obtain a mixed filler;

[0026] (2) mixing a mixed filler, anhydrous ethanol and γ-aminopropyltriethoxysilane in a weight ratio of 1:(7-9):(0.2-0.5), stirring and reacting at 55-60° C. for 4-6 hours, filtering, washing and drying to obtain a silane-modified filler;

[0027] (3) Mix silane-modified filler, anhydrous ethanol, glycidyl methacrylate and azobisisobutyronitrile in weight parts of 1: (6-8): (0.12-0.17): (0.01-0.03), heat and stir at 65-70° C. for 8-10 h, filter, wash and dry to obtain a modified filler.

[0028] Furthermore, the particle size of nano calcium carbonate is 50-100nm, the average particle size is 70nm, and the specific surface area is 40-50m 2 / g; the particle size of nano zinc oxide is 30-50nm, the average particle size is 45nm, and the specific surface area is 15-30m 2 / g; the particle size of nano-silicon dioxide is 5-20nm, the average particle size is 15nm, and the specific surface area is 200-250m 2 / g.

[0029] Furthermore, the weight ratio of nano calcium carbonate, nano zinc oxide and nano silicon dioxide is 1:(0.3-0.5):(1.5-1.8).

[0030] Medical gloves need to have solvent resistance, mainly because in medical environments, gloves may come into contact with various chemicals and solvents, which may destroy the structural integrity of the gloves and affect their protective function. The present invention attempts to add nanofillers to improve the solvent resistance of waterborne polyurethane, but the effect is not ideal. By modifying the nanofillers, the solvent resistance of waterborne polyurethane can be improved. Analysis shows that by modifying the filler, the compatibility with other components in the system can be improved, and a strong interface bond is formed between the nanofillers and the polyurethane matrix, which enhances the interface strength of the matrix, thereby improving the solvent resistance of the material.

[0031] The invention provides a method for preparing the water-based polyurethane for medical gloves. The method comprises the following steps: uniformly mixing polyurethane A, polyurethane B, a surfactant, a modified filler, caprolactam and deionized water, and ultrasonicating for 15-20 minutes to obtain the water-based polyurethane for medical gloves.

[0032] The invention provides application of the waterborne polyurethane in preparing medical gloves.

[0033] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0034] 1. The present invention uses double-terminated hydroxyl polyether modified silicone oil to prepare polyurethane A, which can improve the tensile strength of water-based polyurethane for medical gloves.

[0035] 2. The present invention compounds polyurethane A prepared from polyether polyol and polyurethane B prepared from polyester polyol to improve the elongation at break of waterborne polyurethane and the puncture strength of waterborne polyurethane used in medical gloves.

[0036] 3. The present invention can improve the tensile strength and elongation at break of waterborne polyurethane after irradiation by using polyether polyols with a specific ratio and polyester polyols with a specific ratio.

[0037] 4. The present invention uses a specific surfactant to improve the stability of waterborne polyurethane.

[0038] 5. The present invention can improve the solvent resistance of waterborne polyurethane by modifying the nanofiller. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The raw materials of the present invention are purchased from the following manufacturers:

[0041] The double-terminated hydroxyl polyether modified silicone oil was purchased from Qingdao Baisenmao New Materials Co., Ltd., model BM-13667.

[0042] Polyether diol with a hydroxyl number of 36-39 mgKOH / g was purchased from Xuzhou Yihuiyang New Materials Co., Ltd., DL-3000D.

[0043] The polyether triol with a hydroxyl number of 535 mgKOH / g was purchased from Arkema, France, model number TO330.

[0044] Polyether diol with hydroxyl number of 153-188 mgKOH / g was purchased from Jining Tangyi Chemical Co., Ltd., HSH-310.

[0045] Polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g, and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g were all purchased from Green Union (Jining) Chemical Technology Co., Ltd.

[0046] Nonylphenol polyoxyethylene ether was purchased from Shandong Xiaoqing New Chemical Co., Ltd., model NP-40.

[0047] Disodium octadecyl succinamide sulfonate, CAS: 14481-60-8.

[0048] The nano calcium carbonate in the examples of the present invention was purchased from Shanghai Gerunya Nano Materials Co., Ltd. The nano zinc oxide was purchased from Zhejiang Zhiti Nano Micro New Materials Co., Ltd. The nano silicon dioxide was purchased from Beijing Dekedaojin Technology Co., Ltd.

[0049] Example 1

[0050] This embodiment provides a water-based polyurethane for medical gloves, comprising the following components in parts by weight: 37 parts of polyurethane A, 16 parts of polyurethane B, 9 parts of surfactant, 9 parts of modified filler, 4 parts of caprolactam and 73 parts of deionized water.

[0051] The preparation method of polyurethane A comprises the following steps: by weight,

[0052] (1) 0.4 parts of double-terminal hydroxyl polyether modified silicone oil, 17 parts of polyether polyol, 6 parts of dimethylol propionic acid, and 5 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol (CAS: 23147-57-1) were mixed, heated to 95°C with stirring, vacuum dehydrated for 2.5 hours under -0.1 MPa, cooled to 27°C, 47 parts of isophorone diisocyanate were added, heated to 82°C with stirring, kept warm for 2.5 hours, and cooled. To 52 ° C, continue to add 52 parts of acetone, stir and heat to 75 ° C for reaction 8 hours, then cool to 18 ° C, add 3.2 parts of triethylamine and 210 parts of acetone, stir for 45 minutes to obtain prepolymer A; the polyether polyol includes a polyether diol with a hydroxyl number of 36-39 mgKOH / g, a polyether triol with a hydroxyl number of 535 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g in a weight ratio of 1.4:0.4:1.

[0053] (2) Under stirring conditions of 1300 r / min, 455 parts of an ice-water mixture were added to prepolymer A, stirred for 12 min, and then the speed was adjusted to 550 r / min, and a solution consisting of 2.3 parts of ethylenediamine and 11 parts of water was added, and stirring was continued for 4.5 h to obtain emulsion A;

[0054] (3) The emulsion A was heated to 42°C and acetone was removed under -0.09 MPa to obtain polyurethane A.

[0055] The preparation method of polyurethane B comprises the following steps in parts by weight:

[0056] (1) 17 parts of polyester polyol, 6 parts of dimethylol propionic acid, and 5 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol were mixed, heated to 95°C with stirring, vacuum dehydrated for 2.5 hours under -0.1 MPa, cooled to 27°C, 47 parts of isophorone diisocyanate were added, heated to 82°C with stirring, kept warm for reaction for 2.6 hours, cooled to 52°C, 52 parts of acetone were added, heated to 75°C with stirring for reaction for 8 hours, then cooled to 17°C, added 3.2 parts of triethylamine and 210 parts of acetone were added and stirred for 45 minutes to obtain prepolymer B; the polyester polyol included polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g, and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g in a weight ratio of 1.3:1:0.4.

[0057] (2) Under the stirring condition of 1300 r / min, 455 parts of ice-water mixture were added to prepolymer B, stirred for 12 min, then the speed was adjusted to 550 r / min, and a solution consisting of 2.2 parts of ethylenediamine and 11 parts of water was added, and stirring was continued for 4.5 h to obtain emulsion B;

[0058] (3) The emulsion B was heated to 42°C and acetone was removed under -0.09 MPa to obtain polyurethane B.

[0059] The surfactant is Tween 60, nonylphenol polyoxyethylene ether and disodium octadecyl succinamide sulfonate in a weight ratio of 1:1.4:0.6.

[0060] The preparation method of the modified filler comprises the following steps:

[0061] (1) Mixing nano calcium carbonate, nano zinc oxide and nano silicon dioxide in a weight ratio of 1:0.4:1.7 to obtain a mixed filler; the particle size of the nano calcium carbonate is 50-100 nm, the average particle size is 70 nm, and the specific surface area is 40-50 m 2 / g; the particle size of nano zinc oxide is 30-50nm, the average particle size is 45nm, and the specific surface area is 15-30m 2 / g; the particle size of nano-silicon dioxide is 5-20nm, the average particle size is 15nm, and the specific surface area is 200-250m 2 / g.

[0062] (2) mixing a mixed filler, anhydrous ethanol and γ-aminopropyltriethoxysilane in a weight ratio of 1:8:0.4, stirring and reacting at 52° C. for 5 h, filtering, washing and drying to obtain a silane-modified filler;

[0063] (3) Mix silane-modified filler, anhydrous ethanol, glycidyl methacrylate and azobisisobutyronitrile in weight parts of 1:7:0.15:0.02, heat and stir at 68° C. for 9 h, filter, wash and dry to obtain a modified filler.

[0064] The weight ratio of nano calcium carbonate, nano zinc oxide and nano silicon dioxide is 1:0.4:1.7.

[0065] The preparation method of the water-based polyurethane for medical gloves comprises the following steps: uniformly mixing polyurethane A, polyurethane B, a surfactant, a modified filler, caprolactam and deionized water, and ultrasonicating for 18 minutes to obtain the water-based polyurethane for medical gloves.

[0066] Example 2

[0067] This embodiment provides a water-based polyurethane for medical gloves, comprising the following components in parts by weight: 35 parts of polyurethane A, 18 parts of polyurethane B, 8 parts of surfactant, 7 parts of modified filler, 2 parts of caprolactam and 75 parts of deionized water.

[0068] The preparation method of polyurethane A comprises the following steps: by weight,

[0069] (1) 0.3 parts of double-terminal hydroxyl polyether modified silicone oil, 20 parts of polyether polyol, 5 parts of dimethylol propionic acid, and 6 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol were mixed, heated to 94°C with stirring, vacuum dehydrated for 3 hours under -0.1MPa, cooled to 25°C, 50 parts of isophorone diisocyanate were added, stirred and heated to 80°C, kept warm for 3 hours, cooled to 55°C, and 50 parts of isophorone diisocyanate were added. 0 parts of acetone, stirred and heated to 76 ° C for reaction for 7 hours, then cooled to 20 ° C, added 3.0 parts of triethylamine and 220 parts of acetone, stirred for 40 minutes to obtain prepolymer A; the polyether polyol includes a polyether diol with a hydroxyl number of 36-39 mgKOH / g, a polyether triol with a hydroxyl number of 535 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g in a weight ratio of 1.3:0.5:1.

[0070] (2) Under stirring conditions of 1200 r / min, 460 parts of an ice-water mixture were added to prepolymer A, stirred for 10 min, and then the speed was adjusted to 600 r / min, and a solution consisting of 2 parts of ethylenediamine and 12 parts of water was added, and stirring was continued for 4 h to obtain emulsion A;

[0071] (3) The emulsion A was heated to 45°C and acetone was removed under -0.09 MPa to obtain polyurethane A.

[0072] The preparation method of polyurethane B comprises the following steps in parts by weight:

[0073] (1) 15 parts of polyester polyol, 8 parts of dimethylol propionic acid, and 4 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol were mixed, heated to 98°C with stirring, vacuum dehydrated for 3 hours under -0.1 MPa, cooled to 25°C, 50 parts of isophorone diisocyanate were added, stirred and heated to 80°C, kept warm for reaction for 3 hours, cooled to 50°C, 55 parts of acetone were added, stirred and heated to 74°C for reaction for 9 hours, then cooled to 15°C, 3 .5 parts of triethylamine and 220 parts of acetone, stirred for 40 minutes, to obtain prepolymer B; the polyester polyol includes polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g in a weight ratio of 1.2:1:0.5.

[0074] (2) Under stirring conditions of 1400 r / min, 450 parts of an ice-water mixture were added to prepolymer B, stirred for 15 min, and then the speed was adjusted to 500 r / min, and a solution consisting of 2.5 parts of ethylenediamine and 12 parts of water was added, and stirring was continued for 4 h to obtain emulsion B;

[0075] (3) The emulsion B was heated to 45°C and acetone was removed under -0.09 MPa to obtain polyurethane B.

[0076] The surfactant is Tween 60, nonylphenol polyoxyethylene ether and disodium octadecyl succinamide sulfonate in a weight ratio of 1:1.2:0.8.

[0077] The preparation method of the modified filler comprises the following steps:

[0078] (1) Mixing nano calcium carbonate, nano zinc oxide and nano silicon dioxide in a weight ratio of 1:0.3:1.8 to obtain a mixed filler; the particle size of the nano calcium carbonate is 50-100 nm, the average particle size is 70 nm, and the specific surface area is 40-50 m 2 / g; the particle size of nano zinc oxide is 30-50nm, the average particle size is 45nm, and the specific surface area is 15-30m 2 / g; the particle size of nano-silicon dioxide is 5-20nm, the average particle size is 15nm, and the specific surface area is 200-250m 2 / g.

[0079] (2) mixing a mixed filler, anhydrous ethanol and γ-aminopropyltriethoxysilane in a weight ratio of 1:7:0.2, stirring and reacting at 60° C. for 4 h, filtering, washing and drying to obtain a silane-modified filler;

[0080] (3) Mix silane-modified filler, anhydrous ethanol, glycidyl methacrylate and azobisisobutyronitrile in weight parts of 1:6:0.12:0.03, heat and stir at 65° C. for 10 h, filter, wash and dry to obtain a modified filler.

[0081] The weight ratio of nano calcium carbonate, nano zinc oxide and nano silicon dioxide is 1:0.3:1.8.

[0082] The preparation method of the water-based polyurethane for medical gloves comprises the following steps: uniformly mixing polyurethane A, polyurethane B, a surfactant, a modified filler, caprolactam and deionized water, and ultrasonicating for 15 minutes to obtain the water-based polyurethane for medical gloves.

[0083] Comparative Example 1

[0084] The difference between this comparative example and Example 1 is that 37 parts of polyurethane A and 16 parts of polyurethane B are replaced by 30 parts of polyurethane A and 23 parts of polyurethane B.

[0085] Comparative Example 2

[0086] The difference between this comparative example and Example 1 is that the polyether polyol includes a polyether diol having a hydroxyl number of 36-39 mgKOH / g, a polyether triol having a hydroxyl number of 535 mgKOH / g, and a polyether diol having a hydroxyl number of 153-188 mgKOH / g in a weight ratio of 1:1:1.

[0087] Comparative Example 3

[0088] The difference between this comparative example and Example 1 is that the polyester polyol includes polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g, and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g in a weight ratio of 1:1:1.

[0089] Comparative Example 4

[0090] The difference between this comparative example and Example 1 is that the surfactant is Tween 60, nonylphenol polyoxyethylene ether and disodium octadecyl succinamide sulfonate in a weight ratio of 1:1:1.

[0091] Comparative Example 5

[0092] The difference between this comparative example and Example 1 is that the surfactant is Span 80, sodium lauryl sulfate and sodium lauryl sulfate in a weight ratio of 1:1.4:0.6.

[0093] Comparative Example 6

[0094] The difference between this comparative example and Example 1 is that the weight ratio of nano calcium carbonate, nano zinc oxide and nano silicon dioxide is 1:1:1. The particle size of nano calcium carbonate is 50-100nm, the average particle size is 70nm, and the specific surface area is 40-50m 2 / g; the particle size of nano zinc oxide is 30-50nm, the average particle size is 45nm, and the specific surface area is 15-30m 2 / g; the particle size of nano-silicon dioxide is 5-20nm, the average particle size is 15nm, and the specific surface area is 200-250m 2 / g.

[0095] Comparative Example 7

[0096] The difference between this comparative example and Example 1 is that the particle size of nano calcium carbonate is 150-200nm, the average particle size is 165nm, and the specific surface area is 10-20m 2 / g; the particle size of nano zinc oxide is 70-100nm, the average particle size is 85nm, and the specific surface area is 5-10m 2 / g; the particle size of nano-silicon dioxide is 45-60nm, the average particle size is 55nm, and the specific surface area is 100-140m 2 / g.

[0097] Performance Testing

[0098] Using the water-based polyurethane for medical gloves prepared in Examples 1-2 and Comparative Examples 1-7, a film sample was prepared by dipping using a glass mold with a diameter of 40 mm. After the film was formed, it was dried in a drying oven at 90° C. for 35 minutes to obtain a sample with a thickness of 20 μm. Performance tests were performed.

[0099] (1) Tensile property test: The test was conducted using a universal tensile testing machine in accordance with the method described in GB / T528-2009. The sample was a dumbbell-shaped sheet. The tensile rate was 300 mm / min and the temperature was 25°C.

[0100] (2) Puncture strength test: refer to GB / T10004-2008 standard test, cut the sample into strips with scissors, install the test piece with a width of 100 mm on the sample film fixing clamp ring, and then use a steel needle with a diameter of 1.0 mm and a top radius of 0.1 mm to puncture the test piece at a speed of (50±5) mm / min, and read the maximum load of the steel needle penetrating the test piece; test 3 points and take the arithmetic mean.

[0101] (3) Solvent resistance: The sample was completely immersed in 350 mPa.S silicone oil for 48 h, and the tensile properties were measured.

[0102] (4) Storage stability: Take 100 mL of the aqueous polyurethane prepared in Examples 1-2 and Comparative Examples 1-7, seal it in a transparent sample bottle and put it in a constant temperature drying oven. After 7 days at 50°C, take it out and place it at 25°C for 3 hours. Visually observe its appearance to see if there is any precipitation.

[0103] Table 1 Performance test results

[0104]

[0105] It can be seen from the above performance test results that the comprehensive performance of the waterborne polyurethanes of Examples 1-2 is excellent, especially the comprehensive performance of Example 1 is the most outstanding, which is mainly due to the synergistic compounding of multiple components.

[0106] However, the comparative examples are obviously inferior to the embodiments in the corresponding performance tests because they do not adopt the necessary technical solutions. In comparative example 1, the ratio of polyurethane A and polyurethane B is changed, and it can be seen that the tensile strength and elongation at break are reduced, proving that the compounding scheme of polyurethane A and polyurethane B has an important influence on the tensile strength and elongation at break of waterborne polyurethane. The changes in the ratio of polyether polyol and polyester polyol in comparative examples 2 and 3 can be seen from the results that the radiation resistance of waterborne polyurethane is reduced; comparative examples 4 and 5 change the raw materials and ratio of surfactants, which affects the stability of waterborne polyurethane; comparative examples 6 and 7 change the ratio of fillers and parameters, and the solvent resistance of waterborne polyurethane is reduced. The above experimental results further prove the importance of the technical solution defined in the present invention for its technical effect.

[0107] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A water-based polyurethane for medical gloves, characterized in that: The invention comprises the following components in parts by weight: 35-40 parts of polyurethane A, 14-18 parts of polyurethane B, 8-12 parts of surfactant, 7-11 parts of modified filler, 2-5 parts of caprolactam and 70-75 parts of deionized water; The preparation method of polyurethane A comprises the following steps: by weight, (1) Mix 0.3-0.5 parts of double-terminal hydroxyl polyether modified silicone oil, 15-20 parts of polyether polyol, 5-8 parts of dimethylol propionic acid, and 4-6 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol, stir and heat to 94-98°C, vacuum dehydrate, cool to 25-30°C, add 45-50 parts of diisocyanate, stir and heat to 80-85°C, and keep warm for 2-3 hours , cool to 50-55°C, continue to add 50-55 parts of acetone, stir and heat to 74-76°C for reaction for 7-9h, then cool to 15-20°C, add 3.0-3.5 parts of triethylamine and 200-220 parts of acetone, stir for 40-50min to obtain prepolymer A; the diisocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate; (2) Under stirring conditions of 1200-1400 r / min, add 450-460 parts of ice-water mixture to prepolymer A, stir for 10-15 minutes, then adjust the speed to 500-600 r / min, add a solution consisting of 2-2.5 parts of ethylenediamine and 10-12 parts of water, and continue stirring for 4-5 hours to obtain emulsion A; (3) The emulsion A is heated to 40-45°C and the acetone is removed to obtain polyurethane A.

2. The aqueous polyurethane for medical gloves according to claim 1, characterized in that: The polyether polyols include polyether diols with a hydroxyl number of 36-39 mgKOH / g, polyether triols with a hydroxyl number of 535 mgKOH / g, and polyether diols with a hydroxyl number of 153-188 mgKOH / g in a weight ratio of (1.3-1.5):(0.2-0.5):

1.

3. The aqueous polyurethane for medical gloves according to claim 1, characterized in that: The preparation method of polyurethane B comprises the following steps in parts by weight: (1) 15-20 parts of polyester polyol, 5-8 parts of dimethylol propionic acid and 4-6 parts of 2,3,5,6-tetramethyl-1,4-dioxacyclo-2,5-diol are mixed, heated to 94-98°C with stirring, vacuum dehydration is performed, the temperature is lowered to 25-30°C, 45-50 parts of isophorone diisocyanate are added, the temperature is raised to 80-85°C with stirring, the temperature is kept for reaction for 2-3 hours, the temperature is lowered to 50-55°C, 50-55 parts of acetone are added, the temperature is raised to 74-76°C with stirring and the reaction is carried out for 7-9 hours, the temperature is then lowered to 15-20°C, 3.0-3.5 parts of triethylamine and 200-220 parts of acetone are added, and the temperature is stirred for 40-50 minutes to obtain prepolymer B; (2) Under stirring conditions of 1200-1400 r / min, add 450-460 parts of ice-water mixture to prepolymer B, stir for 10-15 min, then adjust the speed to 500-600 r / min, add a solution consisting of 2-2.5 parts of ethylenediamine and 10-12 parts of water, and continue stirring for 4-5 hours to obtain emulsion B; (3) The emulsion B is heated to 40-45°C and the acetone is removed to obtain polyurethane B.

4. The aqueous polyurethane for medical gloves according to claim 3, characterized in that: The polyester polyol includes polybutylene adipate diol with a molecular weight of 600 and a hydroxyl value of 185-205 mgKOH / g, polybutylene adipate diol with a molecular weight of 2000 and a hydroxyl value of 53-59 mgKOH / g, and polybutylene adipate diol with a molecular weight of 4000 and a hydroxyl value of 26-30 mgKOH / g in a weight ratio of (1.2-1.4): 1: (0.3-0.5).

5. The aqueous polyurethane for medical gloves according to claim 1, characterized in that: The surfactant is a mixture of Tween 60, nonylphenol polyoxyethylene ether and disodium octadecyl succinamide sulfonate in a weight ratio of 1: (1.2-1.5): (0.5-0.8).

6. The aqueous polyurethane for medical gloves according to claim 1, characterized in that: The preparation method of the modified filler comprises the following steps: (1) mixing nano calcium carbonate, nano zinc oxide and nano silicon dioxide to obtain a mixed filler; (2) Mixing a mixed filler, anhydrous ethanol and γ-aminopropyltriethoxysilane in a weight ratio of 1: (7-9): (0.2-0.5), stirring and reacting at 55-60° C. for 4-6 hours, filtering, washing and drying to obtain a silane-modified filler; (3) Mix silane-modified filler, anhydrous ethanol, glycidyl methacrylate and azobisisobutyronitrile in weight parts of 1: (6-8): (0.12-0.17): (0.01-0.03), heat and stir at 65-70° C. for 8-10 h, filter, wash and dry to obtain a modified filler.

7. The aqueous polyurethane for medical gloves according to claim 6, characterized in that: The particle size of nano calcium carbonate is 50-100nm, the average particle size is 70nm, and the specific surface area is 40-50m 2 / g; the particle size of nano zinc oxide is 30-50nm, the average particle size is 45nm, and the specific surface area is 15-30m 2 / g; the particle size of nano-silicon dioxide is 5-20nm, the average particle size is 15nm, and the specific surface area is 200-250m 2 / g.

8. The aqueous polyurethane for medical gloves according to claim 6, characterized in that: The weight ratio of nano calcium carbonate, nano zinc oxide and nano silicon dioxide is 1: (0.3-0.5): (1.5-1.8).

9. A method for preparing the aqueous polyurethane for medical gloves according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: uniformly mixing polyurethane A, polyurethane B, surfactant, modified filler, caprolactam and deionized water, and ultrasonicating for 15-20 minutes to obtain water-based polyurethane for medical gloves.

10. Use of the waterborne polyurethane according to any one of claims 1 to 8 in the preparation of medical gloves.

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