Solvent-free polyurethane slurry, its manufacturing method, and manufacturing method of resin-coated protective gloves using the solvent-free polyurethane slurry

Abstract

To provide a solvent-free polyurethane slurry or the like that does not use any organic solvent, and to provide a method for producing protective gloves that are free from residual harmful substances, have excellent abrasion resistance, oil resistance, and solvent resistance, and are produced by a simple process at low cost. [Solution] The solventless polyurethane slurry is composed of component A and component B in a mass ratio of component A:component B = 100:(67-93). Component A contains, by mass, components such as 67-93 parts of polyoxypropylene tetraol and 7-24 parts of hydroxyacrylate. Component B contains, by mass, components such as 21-43 parts of polyoxypropylene glycol, 12-25 parts of a polymer containing a terminal hydroxyl group double bond, and 45-61 parts of polyisocyanate. This composition makes it possible to provide a solventless polyurethane slurry that does not use an organic solvent.

Description

[Technical Field]

[0001] The present invention relates to the technical field of polyurethane materials, and in particular to a solvent-free polyurethane slurry and a method for producing the same, and a method for producing environmentally friendly resin-coated protective gloves. [Background technology]

[0002] Currently available polyurethane gloves can be divided into two categories based on the type of polyurethane used. One type is protective gloves made from solvent-based polyurethanes. These gloves offer excellent abrasion resistance, oil resistance, and solvent resistance. However, because the solvent-based polyurethane raw materials and subsequent viscosity adjustment use toxic dimethylformamide, the dimethylformamide solvent remains in the gloves even after repeated immersion and washing. This residual solvent adversely affects the human body and the surrounding environment during the manufacturing process and during use. The other type is protective gloves made from water-based polyurethane emulsions. Because the water-based polyurethane raw materials use water as a solvent, the amount of organic solvent used is significantly reduced, reducing adverse effects on the human body and the environment. However, these gloves have inferior abrasion resistance, oil resistance, and solvent resistance compared to solvent-based polyurethane protective gloves, and are therefore more expensive. Patent Document 1 discloses a solvent-free polyurethane sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2023-552684 Summary of the Invention [Problem to be solved by the invention]

[0004] The solvent-free polyurethane slurry provided by the present invention does not use any organic solvent, and the protective gloves produced do not contain any harmful substances, have excellent abrasion resistance, oil resistance, and solvent resistance, and are produced at low cost through a simple process. [Means for solving the problem]

[0005] In order to achieve the above object of the invention, the present invention provides the following technical solutions: In this specification, the expression "A to B" means "A or more and B or less" unless otherwise specified.

[0006] The present invention provides a solvent-free polyurethane slurry composed of component A and component B in a mass ratio of component A:component B=100:(67 to 93).

[0007] The component A contains, by mass, 67 to 93 parts of polyoxypropylene tetraol, 7 to 24 parts of hydroxyacrylate, 0.3 to 5 parts of an alcohol chain extender, 0.7 to 7 parts of a photoinitiator, 0.03 to 0.7 parts of a delay catalyst, and 0.03 to 0.8 parts of a foam stabilizer, The component B contains, by mass, 21 to 43 parts of polyoxypropylene glycol, 12 to 25 parts of a polymer containing a terminal hydroxyl group and a double bond, 45 to 61 parts of polyisocyanate, and 0.008 to 0.05 parts of a polymerization inhibitor.

[0008] Preferably, the molecular weight of the polyoxypropylene tetraol is 800 to 3,000.

[0009] Preferably, the hydroxyacrylate is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, trimethylolpropane diacrylate, and pentaerythritol triacrylate.

[0010] Preferably, the molecular weight of the polyoxypropylene glycol is 1,000 to 3,000.

[0011] The present invention also provides a method for producing the solvent-free polyurethane slurry, which includes the steps of: mixing the polyoxypropylene tetraol, the hydroxyacrylate, and the alcohol chain extender, sequentially performing a first heating and stirring treatment and a cooling treatment, adding the foam stabilizer, and performing a second heating and stirring treatment to obtain a mixture; mixing the mixture with the photoinitiator and the delay catalyst to obtain the component A; mixing the polyisocyanate and the polymerization inhibitor, performing a third heating and stirring treatment, adding the polyoxypropylene glycol and the hydroxyl-terminated double bond-containing polymer, and sequentially performing a heating reaction and vacuum degassing to obtain the component B; and mixing the component A and the component B to obtain the solvent-free polyurethane slurry.

[0012] The present invention also provides a method for producing a resin-coated protective glove, the method comprising the steps of preheating a glove core-equipped former, coating the surface of the glove core with a penetration inhibitor, impregnating the glove with the solvent-free polyurethane slurry described in claim 1, UV curing, drying, and post-treatment. [Effects of the Invention]

[0013] The present invention provides a solvent-free polyurethane slurry that does not use organic solvents. The resulting protective gloves are free of harmful residues, and the reaction rate and efficiency of component A (polyol component) and component B (prepolymer component) can be controlled by controlling the type and amount of raw materials used. The resulting protective gloves are then instantly cured under UV irradiation, significantly improving the molecular weight and crosslink density of the polymer in the gloves, thereby improving their abrasion resistance, oil resistance, and solvent resistance. The alcohol chain extender is widely available and inexpensive, reducing costs. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram of a manufacturing process for a resin-coated protective glove provided by the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention provides a solvent-free polyurethane slurry composed of component A and component B in a mass ratio of component A:component B=100:(67 to 93). The component A contains, by mass, 67 to 93 parts of polyoxypropylene tetraol, 7 to 24 parts of hydroxyacrylate, 0.3 to 5 parts of an alcohol chain extender, 0.7 to 7 parts of a photoinitiator, 0.03 to 0.7 parts of a delay catalyst, and 0.03 to 0.8 parts of a foam stabilizer, The component B contains, by mass, 21 to 43 parts of polyoxypropylene glycol, 12 to 25 parts of a polymer containing a terminal hydroxyl group and a double bond, 45 to 61 parts of polyisocyanate, and 0.008 to 0.05 parts of a polymerization inhibitor.

[0016] In the present invention, the mass ratio of the A component to the B component is preferably 100:(70 to 90), the A component preferably contains, in parts by mass, 70 to 90 parts of polyoxypropylene tetraol, 10 to 20 parts of hydroxyacrylate, 0.5 to 3 parts of an alcohol chain extender, 1 to 5 parts of a photoinitiator, 0.05 to 0.5 parts of a delay catalyst, and 0.05 to 0.5 parts of a foam stabilizer, and the B component preferably contains, in parts by mass, 25 to 40 parts of polyoxypropylene glycol, 15 to 20 parts of a polymer containing a terminal hydroxyl group double bond, 40 to 65 parts of a polyisocyanate, and 0.01 to 0.03 parts of a polymerization inhibitor.

[0017] In the present invention, the polyoxypropylene tetraol preferably does not contain ethylene oxide repeating units in a liquid state, and its molecular weight is preferably 1000 to 3000. The hydroxyacrylate is preferably at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, trimethylolpropane diacrylate, and pentaerythritol triacrylate. The alcohol chain extender is preferably at least one of ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, methyldiethanolamine, and dihydroxyethylaniline. The photoinitiator is preferably at least one of 2-hydroxymethylphenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, and 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone. The delay catalyst is preferably DY-215 or Niax. A-510, and the foam stabilizer is preferably a polysiloxane-oxyalkylene block copolymer or a polysiloxane-oxyalkylene graft copolymer.

[0018] In the present invention, the polyoxypropylene glycol preferably does not contain an ethylene oxide repeating unit and preferably has a molecular weight of 1,000 to 3,000, the polymer having a terminal hydroxyl double bond is preferably at least one of hydroxyl-terminated polybutadiene, hydroxyl-terminated hydrogenated polybutadiene, hydroxyl-terminated epoxidized polybutadiene resin, and hydroxyl-terminated polyisoprene, the polymerization inhibitor is preferably phosphoric acid or benzoyl chloride, and the polyisocyanate is preferably composed of diphenylmethylene diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, and MDI-50 in a mass ratio of (70 to 90):(5 to 20):(1 to 10).

[0019] The present invention also provides a method for producing the solvent-free polyurethane slurry, comprising the steps of: mixing the polyoxypropylene tetraol, the hydroxyacrylate, and the alcohol chain extender, sequentially performing a first heating and stirring treatment and a cooling treatment, adding the foam stabilizer, and performing a second heating and stirring treatment to obtain a mixture; mixing the mixture with the photoinitiator and the delay catalyst to obtain the A component; mixing the polyisocyanate and the polymerization inhibitor, followed by a third heating and stirring treatment, adding the polyoxypropylene glycol and the hydroxyl-terminated double bond-containing polymer, and sequentially performing a heating reaction and vacuum degassing to obtain the B component; and mixing the A component and the B component to obtain the solvent-free polyurethane slurry.

[0020] In the present invention, the first heating and stirring time is preferably 1 hour, the temperature is preferably 50 to 55°C, the cooling treatment is preferably cooling to 30 to 40°C, the second heating and stirring time is preferably 2 to 3 hours, the temperature is preferably 30 to 40°C, the third heating and stirring temperature is preferably 50 to 60°C, the heating reaction temperature is preferably 65 to 90°C, and the time is preferably 2 to 4 hours, and when the NCO content in the heating reaction system is 10 wt% to 20 wt%, vacuum degassing is performed at -0.08 MPa to -0.1 MPa for 2 to 3 hours.

[0021] The present invention also provides an environmentally friendly resin-coated protective glove produced from the above-mentioned solvent-free polyurethane slurry or the solvent-free polyurethane slurry produced by the above-mentioned production method.

[0022] The present invention also provides a method for manufacturing the above-mentioned environmentally friendly resin-coated protective gloves, which includes the steps of preheating a glove former with a glove core, coating the surface of the glove core with a penetration inhibitor, impregnating gloves with the solvent-free polyurethane slurry described in claim 1, UV-curing the polyurethane slurry in the impregnated gloves, drying the UV-cured gloves, and post-treating the dried gloves.

[0023] In the present invention, the preheating temperature is preferably 30 to 130°C, the penetration inhibitor is preferably at least one of water-based polyurethane, solventless polyurethane, natural latex, nitrile, and liquid silica gel, the coating is performed by dip coating, impregnation, or spraying, the number of times of impregnation with the solventless polyurethane slurry, UV curing, and drying is preferably 1 to 4, the UV curing time is preferably 1 to 10 seconds, the drying temperature is preferably 100 to 140°C, and the drying time is preferably 10 to 90 minutes, and the post-treatment is preferably performed by immersion, spraying, drying, and demolding, in that order.

[0024] The following clearly and completely describes the technical solutions in the present invention in connection with the embodiments of the present invention. The described embodiments are only some of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0025] FIG. 1 is a schematic diagram of the manufacturing process of the environmentally friendly resin-coated protective gloves provided by the present invention.

[0026] Example 1 The solventless polyurethane slurry is composed of component A and component B in a mass ratio of 100:80, and the component A is composed of, by mass, 70 parts of a liquid polyoxypropylene tetraol having a molecular weight of 3,000 and containing no ethylene oxide repeating units, 10 parts of hydroxyethyl acrylate, 0.5 parts of an ethylene glycol alcohol chain extender, 5 parts of a 2-hydroxymethylphenylpropan-1-one photoinitiator, 0.2 parts of a DY-215 delay catalyst, and 0.5 parts of a polysiloxane-oxyalkylene block copolymer foam stabilizer; The component B consisted of, by mass, 25 parts of polyoxypropylene glycol containing no ethylene oxide repeating units and having a molecular weight of 2000, 15 parts of hydroxyl-terminated polybutadiene, 60 parts of polyisocyanate, and 0.02 parts of phosphoric acid as a polymerization inhibitor, and the polyisocyanate was composed of diphenylmethylene diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, and MDI-50 in a mass ratio of 80:15:5.

[0027] The method for producing the solvent-free polyurethane slurry includes the steps of: mixing polyoxypropylene tetraol, hydroxyacrylate, and an alcohol chain extender, performing a first heating and stirring process at 50°C for 1 hour, cooling to 40°C, adding a foam stabilizer, and performing a second heating and stirring process at 40°C for 2 hours to obtain a mixture; mixing the mixture with a photoinitiator and a delay catalyst to obtain component A; mixing polyisocyanate and a polymerization inhibitor, performing a third heating and stirring process at 55°C for 0.5 hours, adding polyoxypropylene glycol and hydroxyl-terminated hydrogenated polybutadiene, performing a heating reaction at 80°C for 2 hours, and when the NCO content in the heating reaction system is 17 wt%, vacuum degassing at -0.08 MPa for 2 hours to obtain component B; and mixing component A and component B to obtain the solvent-free polyurethane slurry.

[0028] Application example 1 The manufacturing method for environmentally friendly resin-coated protective gloves will be explained using Figure 1. In step 01 (hereinafter referred to as "S01"), a nylon glove core and hand mold are preheated to 70°C. Next, in step S02, the surface of the glove core is coated with a water-based polyurethane permeation inhibitor. In step S03, the solvent-free polyurethane slurry described in Example 1 is impregnated. In step S04, UV curing is performed for 2 seconds. In step S05, drying is performed. In step S06, post-treatments such as dipping, spraying, drying, and demolding are performed. This results in an environmentally friendly resin-coated protective glove.

[0029] The above are only preferred embodiments of the present invention. It should be noted that those skilled in the art can make some improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be regarded as within the protection scope of the present invention.

Claims

1. A solvent-free polyurethane slurry, which is composed of component A and component B in a mass ratio of component A:component B=100:(67 to 93), The component A contains, in parts by mass, 67 to 93 parts of polyoxypropylene tetraol, 7 to 24 parts of hydroxyacrylate, 0.3 to 5 parts of an alcohol chain extender, 0.7 to 7 parts of a photoinitiator, 0.03 to 0.7 parts of a delay catalyst, and 0.03 to 0.8 parts of a foam stabilizer, The component B contains, in parts by mass, 21 to 43 parts of polyoxypropylene glycol, 12 to 25 parts of a polymer containing a terminal hydroxyl group and a double bond, 45 to 61 parts of a polyisocyanate, and 0.008 to 0.05 parts of a polymerization inhibitor. A solvent-free polyurethane slurry characterized by:

2. The molecular weight of the polyoxypropylene tetraol is 800 to 3000.

2. The solvent-free polyurethane slurry according to claim 1.

3. The hydroxyacrylate is at least one of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, trimethylolpropane diacrylate, and pentaerythritol triacrylate.

2. The solvent-free polyurethane slurry according to claim 1.

4. The molecular weight of the polyoxypropylene glycol is 1,000 to 3,000.

2. The solvent-free polyurethane slurry according to claim 1.

5. mixing the polyoxypropylene tetraol, the hydroxyacrylate, and the alcohol chain extender, sequentially performing a first heating and stirring treatment and a cooling treatment, adding the foam stabilizer, and performing a second heating and stirring treatment to obtain a mixture; mixing the mixture with the photoinitiator and the delay catalyst to obtain the A component; a step of mixing the polyisocyanate and the polymerization inhibitor, performing a third heating and stirring process, adding the polyoxypropylene glycol and the hydroxyl-terminated double bond-containing polymer, and sequentially performing a heating reaction and vacuum degassing to obtain the component B; mixing the A component and the B component to obtain the solvent-free polyurethane slurry; 2. The method for producing a solvent-free polyurethane slurry according to claim 1.

6. preheating a hand mold with a glove core; coating the surface of the glove core with a permeation inhibitor; impregnating the solventless polyurethane slurry of claim 1; UV curing step; A drying step, post-processing, A method for producing a resin-coated protective glove.

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