High-performance polyurethane sling and processing technology thereof

Abstract

The invention discloses a high-performance polyurethane sling and a processing technology thereof, and relates to the technical field of high-performance spandex, the high-performance polyurethane sling comprises a base band and a polyurethane braid arranged on the surface of the base band; the polyurethane braid is formed by weaving spandex filaments; the spandex filament is prepared from the following components in parts by mass: 100 parts of polyurethane prepolymer, 8-12 parts of chain extender, 0-1.5 parts of initiator, 0-6 parts of epoxy resin, 0-0.5 part of organic tin catalyst and solvent. The polyurethane braid contains the spandex filaments, is mainly obtained through the reaction of the polyurethane prepolymer and the chain extender, has good elasticity, wear resistance and mechanical strength, and is arranged on the surface of the base band as a protective layer, so that the wear resistance of the surface of the sling can be effectively improved, the friction force between the contact surfaces of a hoisted object and the sling is increased, and sliding is prevented; the anti-abrasion, anti-skid and anti-aging effects are achieved, the service life of the hanging belt is prolonged, and the fluffing and line displacement phenomena of the hanging belt are delayed.

Description

Technical Field

[0001] This invention relates to the field of high-performance spandex technology, specifically a high-performance polyurethane suspender strap and its processing technology. Background Technology

[0002] Lifting slings are flexible load-bearing tools used for cargo handling and installation, widely applied in lifting operations in industrial production, transportation, loading and unloading, curtain wall installation, machine tool positioning, and other fields. The main raw material for lifting slings is industrial synthetic fiber filaments, which are woven into flexible rigging. Materials include nylon fiber, polyester fiber, and polypropylene fiber, offering advantages such as light weight and high strength, gradually replacing steel wire rope slings. Due to the relatively soft material of synthetic fiber lifting slings, although they possess high strength and load-bearing capacity, their wear and tear must be carefully monitored during actual use. Lifting slings are prone to wear during use, which can shorten their service life and affect their continued use. Therefore, we propose a high-performance polyurethane lifting sling and its processing technology. Summary of the Invention

[0003] The purpose of this invention is to provide a high-performance polyurethane sling and its processing technology to solve the problems mentioned in the background art.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a high-performance polyurethane sling, comprising a base belt and a polyurethane webbing disposed on the surface of the base belt.

[0005] Furthermore, polyurethane webbing is fitted onto the outer wall of the base tape or laminated onto the surface of the base tape; Composite processes include, but are not limited to, sewing, thermal bonding, gluing, and weaving.

[0006] In the above technical solution, polyurethane webbing, as an organic polymer material, has good toughness and wear resistance. When it is used as a protective layer on the surface of the base belt, it can effectively improve the surface wear resistance of the sling. It can also increase the friction between the hoisted item and the contact surface of the sling, prevent slippage, and play a role in anti-wear, anti-slip, and anti-aging, thus extending the service life of the sling and delaying the phenomenon of fraying and thread slippage.

[0007] Furthermore, the polyurethane webbing is woven from spandex filaments; The spandex filament is prepared from the following components by weight: 100 parts polyurethane prepolymer, 8-12 parts chain extender, 0-1.5 parts initiator, 0-6 parts epoxy resin, 0-0.5 parts organotin catalyst and solvent.

[0008] Furthermore, the polyurethane prepolymer is obtained by reacting a polymeric diol with a diisocyanate.

[0009] Furthermore, the polymer polyol is one or more of polycarbonate diol, polytetrahydrofuran ether diol, and polybutylene adipate diol, with a molecular weight of 1000-2000.

[0010] Furthermore, the diisocyanate is one or a mixture of isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4-diisocyanate (HMDI), 2,4-toluene diisocyanate (TDI), and 4,4'-diphenylmethane diisocyanate (MDI).

[0011] Furthermore, in the polymer diol and diisocyanate, the ratio of NCO / OH is (3-4):2.

[0012] Furthermore, the chain extender is one or a mixture of 1,4-butanediol, bis(sec-butylamino)diphenylmethane, 3,3′-dichloro-4,4′-diaminodiphenylmethane, allyl alcohol, methyl allyl alcohol, 2,2-di(hydroxymethyl)-1-butene, 1,4-butenediol, and trimethylolpropane diallyl ether.

[0013] Furthermore, the solvent is N,N-dimethylformamide.

[0014] Furthermore, the organotin catalyst is one of dibutyltin dilaurate and stannous octoate.

[0015] In the above technical solution, the polyurethane webbing contains spandex filaments, which are mainly formed by the reaction of polyurethane prepolymer and chain extender. The polyurethane prepolymer is obtained by reacting polymer diol and diisocyanate. Through the block division of rigid and flexible chain segments, it exerts a synergistic effect, enabling the spandex filaments to exhibit good elasticity, abrasion resistance and mechanical strength.

[0016] Chain extenders, selected from compounds containing hydroxyl or amino groups, react with isocyanate groups in the prepolymer to form urethane or urea groups, creating a cross-linked structure. This enhances the prepolymer's resistance to impact and wear, improving the mechanical properties, surface abrasion resistance, and anti-slip properties of the surface layer. When unsaturated chain extenders (such as 1,4-butenediol) are chosen, free radical polymerization occurs under the action of an initiator, increasing the cross-linking of the polyurethane system. This contributes to improving the overall mechanical properties, abrasion resistance, and other comprehensive properties of spandex filaments and the polyurethane webbing made from them.

[0017] A processing technology for a high-performance polyurethane sling includes the following steps: The prepolymer is mixed with a solvent, and a chain extender, epoxy resin, organotin catalyst, and initiator are added to obtain a spinning solution; the solution is spun, coagulated, and irradiated to obtain spandex yarn. Weaving yields polyurethane webbing; applying it to the surface of a base tape yields polyurethane slings.

[0018] Furthermore, the prepolymer is prepared by the following process: The polymer polyol is heated to 50-60°C, diisocyanate is added, the temperature is raised to 78-84°C, and the mixture is stirred for 90-120 minutes to obtain a prepolymer with an NCO content of 4%-6%.

[0019] Furthermore, the spinning solution comprises the following components by weight: 100 parts polyurethane prepolymer, 8-12 parts chain extender, 3-6 parts epoxy resin, 0.5-1.5 parts initiator, 0.1-0.3 parts organotin catalyst, and 300-400 parts solvent.

[0020] Furthermore, the epoxy resin is prepared by the following process: In a nitrogen atmosphere, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene are dissolved in tetrahydrofuran by stirring. A catalyst is added, and the reaction is carried out for 100-150 min. The mixture is then rotary evaporated, precipitated with n-hexane, filtered, and dried to obtain epoxy resin.

[0021] Furthermore, the molar ratio of fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene is 1:(9-15):(5-11):(4-8).

[0022] Furthermore, the fluorinated acrylate is one of allyl trifluoroacetate, ethyl tetrafluoroacrylate, propyl pentafluoroacrylate, and trifluoromethyl methacrylate.

[0023] Furthermore, the catalyst is Grubbs II, and the amount used is 0.5 to 1.0‰ of the molar amount of cyclohexene.

[0024] Furthermore, the ratio of fluorinated acrylate to tetrahydrofuran is (5-10) g / 100mL.

[0025] Furthermore, the reagents and environment used for epoxy resin were treated to be anhydrous and oxygen-free.

[0026] Furthermore, the chain extender is one or a mixture of allyl alcohol, methyl allyl alcohol, 2,2-di(hydroxymethyl)-1-butene, 1,4-butenediol, and trimethylolpropane diallyl ether.

[0027] Furthermore, the initiator is one or a mixture of two of the following: a photoinitiator and a photoalkalizing agent; The photoinitiator is one or a mixture of 2-hydroxy-2-methyl-1-phenyl-1-propanone (HMPP, Irgacure 1173), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO), diphenyliodonium hexafluorophosphate (DPI-PF6), and benzophenone (BP); The photo-alkali-generating agent is one of o-nitrobenzylcyclohexylcarbamate (NBCHC), benzoylmethyltriethylcarbamate (BTEAC), and tetramethylammonium paraben (TMAB).

[0028] Furthermore, in the spinning process, the spinneret temperature is 60–70°C, and the air section temperature is 25–40°C. The fineness of spandex yarn is 100-300D.

[0029] Furthermore, in the coagulation process, the coagulation bath uses a 25-30 v% N,N-dimethylformamide / water solution at 22-25°C, and then is transferred to a 12-18 v% N,N-dimethylformamide / water solution at 12-18°C. After coagulation bath, the material is stretched in hot water at 60–90°C; then heat-set. The heat setting process is as follows: heat set at 150-170℃ for 20-30 seconds, and then heat set at 130-150℃ for 25-35 seconds.

[0030] Furthermore, irradiation processes include coagulation bath irradiation and secondary irradiation; The coagulation bath is irradiated in the coagulation bath for initial solidification, with an ultraviolet wavelength of 300-405nm, a light intensity of 50-60mW / cm², and a duration of 10-15s. Secondary irradiation is performed after stretching, with an ultraviolet wavelength of 300–405 nm, a light intensity of 50–60 mW / cm², and a duration of 5–10 s.

[0031] Furthermore, the polyurethane webbing has a basis weight of 6–60 g / m, a width of 30–125 mm, and a thickness of 0.5–2 mm.

[0032] In the above technical solution, under the action of a catalyst, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene undergo copolymerization to form a polymer with epoxy groups, norbornene, unsaturated bonds, silicon-oxygen bonds, and fluorinated end groups, which is referred to as epoxy resin. After coagulation in the coagulation bath, under the influence of irradiation, the photoalkali-generating agent photodecomposes to generate alkali, catalyzing the reaction between polyurethane prepolymer, chain extender, and epoxy resin in the spinning solution (such as isocyanate groups with hydroxyl / amino groups, and epoxy resin with hydroxyl / amino groups). This completes the chain extension of polyurethane and the grafting / crosslinking of epoxy resin, and facilitates the hydrolysis and condensation of silicon-oxygen bonds, forming -O-Si-O- crosslinked segments. This significantly improves the hardness, tensile strength, and resistance to damp heat of spandex filaments and the polyurethane webbing made from them. The movement of polyurethane segments is restricted, enhancing the orderliness of the segments, reducing stress relaxation, improving their mechanical properties, reducing plastic deformation during friction, and improving the wear resistance of the surface layer. When unsaturated chain extenders (such as 1,4-butenediol) are selected, they can also participate in free radical polymerization to a certain extent under the action of initiators, increasing the degree of crosslinking of the system. Multifunctional unsaturated chain extenders (such as trimethylolpropane diallyl ether) contribute to the formation of a rough structure and promote the improvement of wet anti-slip ability. Norbornene, with its rigid structure, restricts molecular chain slippage, improving the mechanical strength of spandex filaments and their resulting polyurethane webbing, reducing plastic deformation, resisting surface ploughing effects during friction, and lowering wear. The polymerization of cyclooctene introduces unsaturated linear segments into the epoxy resin, mitigating the surface brittleness caused by the rigid groups, reducing the negative impact of external energy on the performance of the polyurethane webbing, and preventing microcrack formation. The introduction of silica segments improves the low-temperature toughness and weather resistance of spandex filaments and their resulting polyurethane webbing. The introduction of fluorine into the fluorinated end groups, with its low surface energy, allows fluorine to migrate and accumulate on the surface layer, reducing surface polarity and lowering the coefficient of friction, further enhancing the anti-slip performance of the polyurethane webbing. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] In the following specific implementation, Polytetrahydrofuran diol-1000 and polytetrahydrofuran diol-2000 are sourced from Sinopharm Group; Epoxy resin E-44, epoxy equivalent 230g / eq, epoxy value 0.44eq / 100g; The reagents and environment used in the epoxy resin preparation process have all undergone anhydrous and oxygen-free treatment. Spinning process: The spinneret has circular orifices with a diameter of 0.10 mm, a number of orifices N of 30, and an aspect ratio L / D of 3:1; the spinning speed is 550 m / min, the pressure is 1.8 MPa, and the draw ratio is 4.0. Polyurethane webbing, weight 30±1g / m, width 50mm, thickness 0.8±0.05mm; weaving process: 300D / 30F spandex yarn as warp and 75D / 36F polyester (strength 5.2cN / dtex) yarn as weft; warping: spandex tension 12cN, draw ratio 1:3.2, polyester tension 18cN, warping speed: 180m / min; plain weave: warp density 65 ends / 50mm, weft density 26 ends / cm; heat setting at 180℃ for 30s; air cooling; Base strap, polyester flat sling, 50mm wide, 8mm thick, sourced from Jiangsu Zhongyi Rigging Co., Ltd.

[0035] Example 1: A processing technology for a high-performance polyurethane sling, comprising the following processes: Step 1: Under a nitrogen atmosphere, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene are dissolved in tetrahydrofuran by stirring. Grubbs II catalyst (0.5‰ molar amount of cyclohexene) is added, and the reaction is carried out for 150 min. The mixture is then rotary evaporated, precipitated with n-hexane, filtered, and dried to obtain epoxy resin. The molar ratio of fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene is 1:15:5:4. The fluorinated acrylate is allyl trifluoroacetate. The ratio of fluorinated acrylate to tetrahydrofuran is 5 g / 100 mL. The polymer polyol was heated to 50°C, diisocyanate was added, the temperature was raised to 78°C, and the reaction was stirred until the NCO content was 4% to obtain the prepolymer; the polymer polyol was polytetrahydrofuran ether diol-1000; the diisocyanate was 2,4-toluene diisocyanate; the NCO / OH ratio was 3:2. Step 2: Mix the prepolymer with the solvent, add the chain extender, epoxy resin, organotin catalyst, and initiator to obtain the spinning solution. The spinning solution comprises the following components by mass: 100 parts polyurethane prepolymer, 8 parts chain extender, 5 parts epoxy resin, 0.5 parts initiator, 0.1 parts organotin catalyst, and 300 parts solvent N,N-dimethylformamide. The chain extender is 1,4-butanediol and trimethylolpropane diallyl ether in a mass ratio of 3:1. The initiator is TPO and NBCHC in a mass ratio of 3:1. The organotin catalyst is dibutyltin dilaurate. Spinning: In the spinning process, the spinneret temperature is 60℃ and the air section temperature is 25℃; Coagulation: The coagulation bath uses a 26v% N,N-dimethylformamide / water solution at 22℃, which is then transferred to a 12v% N,N-dimethylformamide / water solution at 12℃; Irradiation: Initial curing is performed in the coagulation bath with an ultraviolet wavelength of 365-395nm, a light intensity of 50mW / cm², and a duration of 15s; Stretching is performed in hot water at 60℃; followed by a second irradiation with an ultraviolet wavelength of 365-395nm, a light intensity of 50mW / cm², and a duration of 10s; Heat setting: Heat setting is performed at 150℃ for 30s, followed by heat setting at 130℃ for 35s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0036] Example 2: A processing technology for a high-performance polyurethane sling, comprising the following processes: Step 1: Under a nitrogen atmosphere, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene were dissolved in tetrahydrofuran by stirring. Grubbs II catalyst (0.8‰ molar amount of cyclohexene) was added, and the reaction was carried out for 120 min. The mixture was then rotary evaporated, precipitated with n-hexane, filtered, and dried to obtain epoxy resin. The molar ratio of fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene was 1:12:8:6. The fluorinated acrylate was ethyl tetrafluoroacrylate. The ratio of fluorinated acrylate to tetrahydrofuran was 8 g / 100 mL. The polymer polyol was heated to 55°C, diisocyanate was added, the temperature was raised to 80°C, and the reaction was stirred until the NCO content was 5% to obtain the prepolymer; the polymer polyol was polytetrahydrofuran ether diol-2000; the diisocyanate was 2,4-toluene diisocyanate; the NCO / OH ratio was 7:4. Step 2: Mix the prepolymer with the solvent, add the chain extender, epoxy resin, organotin catalyst, and initiator to obtain the spinning solution. The spinning solution comprises the following components by mass: 100 parts polyurethane prepolymer, 10 parts chain extender, 6.5 parts epoxy resin, 1 part initiator, 0.12 parts organotin catalyst, and 350 parts solvent N,N-dimethylformamide. The chain extender is 1,4-butenediol and trimethylolpropane diallyl ether in a mass ratio of 3:1. The initiator is Irgacure 819 and NBCHC in a mass ratio of 3:1. The organotin catalyst is dibutyltin dilaurate. Spinning: In the spinning process, the spinneret temperature is 65℃ and the air section temperature is 32℃; Coagulation: The coagulation bath uses a 27v% N,N-dimethylformamide / water solution at 23℃, which is then transferred to a 15v% N,N-dimethylformamide / water solution at 15℃; Irradiation: Initial curing is performed in the coagulation bath with an ultraviolet wavelength of 300-405nm, a light intensity of 55mW / cm², and a duration of 12s; Stretching is performed in hot water at 75℃; Then, a second irradiation is performed with an ultraviolet wavelength of 300-405nm, a light intensity of 55mW / cm², and a duration of 8s; Heat setting: Heat setting is performed at 160℃ for 25s, and then at 140℃ for 30s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0037] Example 3: A processing technology for a high-performance polyurethane sling, comprising the following processes: Step 1: Under a nitrogen atmosphere, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene are dissolved in tetrahydrofuran by stirring. Grubbs II catalyst (1.0‰ molar amount of cyclohexene) is added, and the reaction is carried out for 100 min. The mixture is then rotary evaporated, precipitated with n-hexane, filtered, and dried to obtain epoxy resin. The molar ratio of fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene is 1:9:11:8. The fluorinated acrylate is one of allyl trifluoroacetate, ethyl tetrafluoroacrylate, propyl pentafluoroacrylate, and trifluoromethyl methacrylate. The ratio of fluorinated acrylate to tetrahydrofuran is 10 g / 100 mL. The polymer polyol was heated to 60°C, diisocyanate was added, the temperature was raised to 84°C, and the reaction was stirred until the NCO content was 6% to obtain the prepolymer; the polymer polyol was polytetrahydrofuran ether diol-2000; the diisocyanate was 2,4-toluene diisocyanate; the NCO / OH ratio was 2:1. Step 2: Mix the prepolymer with the solvent, add the chain extender, epoxy resin, organotin catalyst, and initiator to obtain the spinning solution. The spinning solution comprises the following components by mass: 100 parts polyurethane prepolymer, 12 parts chain extender, 8 parts epoxy resin, 1.5 parts initiator, 0.3 parts organotin catalyst, and 400 parts solvent N,N-dimethylformamide. The chain extender is trimethylolpropane diallyl ether. The initiator is a mixture of BAPO, BP, and TEOA in a mass ratio of 4:3:3. The organotin catalyst is dibutyltin dilaurate. Spinning: In the spinning process, the spinneret temperature is 70℃ and the air section temperature is 40℃; Coagulation: The coagulation bath uses a 25℃ 32v% N,N-dimethylformamide / water solution, which is then transferred to an 18℃ 18v% N,N-dimethylformamide / water solution; Irradiation: Initial curing is performed in the coagulation bath with an ultraviolet wavelength of 340-395nm, a light intensity of 60mW / cm², and a duration of 10s; Stretching is performed in hot water at 90℃; followed by a second irradiation with an ultraviolet wavelength of 340-395nm, a light intensity of 60mW / cm², and a duration of 5s; Heat setting: Heat setting is performed at 170℃ for 20s, followed by heat setting at 150℃ for 25s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0038] Comparative Example 1: A processing technology for a high-performance polyurethane sling, comprising the following processes: Step 1 is the same as in Example 1; Step 2: Mix the prepolymer with the solvent, add the chain extender, epoxy resin, organotin catalyst, and initiator to obtain the spinning solution; the spinning solution includes the following components by mass: 100 parts polyurethane prepolymer, 8 parts chain extender, 5 parts epoxy resin, 0.5 parts initiator, 0.1 parts organotin catalyst, and 300 parts solvent N,N-dimethylformamide; the chain extender is 1,4-butanediol; the initiator is NBCHC; and the organotin catalyst is dibutyltin dilaurate; Spinning: In the spinning process, the spinneret temperature is 60℃ and the air section temperature is 25℃; Coagulation: The coagulation bath uses a 26v% N,N-dimethylformamide / water solution at 22℃, which is then transferred to a 12v% N,N-dimethylformamide / water solution at 12℃; Irradiation: Initial curing is performed in the coagulation bath with an ultraviolet wavelength of 300-365nm, a light intensity of 50mW / cm², and a duration of 15s; Stretching is performed in hot water at 60℃; followed by a second irradiation with an ultraviolet wavelength of 300-365nm, a light intensity of 50mW / cm², and a duration of 10s; Heat setting: Heat setting is performed at 150℃ for 30s, followed by heat setting at 130℃ for 35s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0039] Comparative Example 2: A processing technology for a high-performance polyurethane sling, comprising the following processes: The prepolymer is mixed with a solvent, and a chain extender, epoxy resin, organotin catalyst, and initiator are added to obtain a spinning solution. The spinning solution comprises the following components by weight: 100 parts polyurethane prepolymer, 8 parts chain extender, 5 parts epoxy resin E-44, 0.5 parts initiator, 0.1 parts organotin catalyst, and 300 parts solvent N,N-dimethylformamide. The chain extender is 1,4-butanediol; the initiator is NBCHC; and the organotin catalyst is dibutyltin dilaurate. Spinning: In the spinning process, the spinneret temperature is 60℃ and the air section temperature is 25℃; Coagulation: The coagulation bath uses a 26v% N,N-dimethylformamide / water solution at 22℃, which is then transferred to a 12v% N,N-dimethylformamide / water solution at 12℃; Irradiation: Initial curing is performed in the coagulation bath with an ultraviolet wavelength of 300-365nm, a light intensity of 50mW / cm², and a duration of 15s; Stretching is performed in hot water at 60℃; followed by a second irradiation with an ultraviolet wavelength of 300-365nm, a light intensity of 50mW / cm², and a duration of 10s; Heat setting: Heat setting is performed at 150℃ for 30s, followed by heat setting at 130℃ for 35s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0040] Comparative Example 3: A processing technology for a high-performance polyurethane sling, comprising the following processes: The prepolymer is mixed with a solvent, and a chain extender, epoxy resin, organotin catalyst, and initiator are added to obtain a spinning solution. The spinning solution comprises the following components by mass: 100 parts polyurethane prepolymer, 8 parts chain extender, 0.1 parts organotin catalyst, and 300 parts solvent N,N-dimethylformamide. The chain extender is 1,4-butanediol, and the organotin catalyst is dibutyltin dilaurate. Spinning: In the spinning process, the spinneret temperature is 60℃ and the air section temperature is 25℃; Coagulation: The coagulation bath uses a 26v% N,N-dimethylformamide / water solution at 22℃, which is then transferred to a 12v% N,N-dimethylformamide / water solution at 12℃; Stretching is performed in hot water at 60℃; Heat setting: Heat setting is performed at 150℃ for 30s, and then at 130℃ for 35s to obtain spandex yarn; The process involves weaving to obtain polyurethane webbing, which is then sewn onto the surface of the base tape to obtain polyurethane suspenders.

[0041] Experiment: Polyurethane webbing obtained in Examples 1-3 and Comparative Examples 1-3 was used to prepare samples. The properties of these samples were tested, and the results were recorded. Abrasion resistance test: Based on GB / T 21196 as the reference standard, the abrasion resistance of polyurethane webbing was tested using a Martindale abrasion tester with a load of 12 kPa. The number of friction cycles when the fabric develops a hole was used as the performance index. Anti-slip performance test: The static friction coefficient of the polyurethane webbing was tested using a friction coefficient tester. The contact surface was a Ra0.8μm stainless steel plate, with a load of 50N and a humidity of 60%RH. Mechanical property testing: The tensile properties of polyurethane webbing were tested using a universal testing machine with reference to GB / T 3923.1; tensile rate 100 mm / min, spacing length 100 mm. Low-temperature mechanical property testing: The polyurethane webbing was subjected to low-temperature impact using a low-temperature impact testing machine to detect the changes in its mechanical properties after the low-temperature impact. The low-temperature impact conditions were: -40℃ constant temperature for 2 hours and impact energy of 5J. The tensile strength retention rate of the specimen after low-temperature impact was used as the performance index. Humid heat aging performance test: The polyurethane webbing was subjected to humid heat aging in a humid heat aging chamber to detect the changes in its mechanical properties after humid heat aging. The humid heat aging conditions were: temperature 85℃, humidity 85%RH, and time 7d. The retention rate of tensile strength of the sample after humid heat aging was used as the performance index.

[0042]

[0043] Based on the data in the table above, the following conclusions can be clearly drawn: The polyurethane webbing obtained in Examples 1-3 is compared with the polyurethane webbing obtained in Comparative Examples 1-3. The test results show that... Compared with the comparative examples, the polyurethane webbing obtained in Examples 1-3 has higher friction cycles, static friction coefficient, tensile strength, and lower mass loss, as well as higher strength retention after low-temperature impact and damp heat. This fully demonstrates that the present invention improves the anti-slip and abrasion-resistant properties, mechanical properties, low-temperature mechanical properties, and weather resistance of polyurethane webbing and the polyurethane slings made from it.

[0044] Compared with Example 1, Comparative Example 1 used a different chain extender and had no alkenyl crosslinking; Comparative Example 2 used different epoxy resins and chain extenders, resulting in poor interfacial bonding and no fluorine modification; Comparative Example 3 did not add epoxy resin, and the chain extender was different, lacking a reinforcing phase. The polyurethane webbing obtained in Comparative Examples 1-3 showed decreased friction cycles, static friction coefficient, and tensile strength, increased mass loss, and lower strength retention after low-temperature impact and damp heat. It can be seen that this invention, through the setting of the polyurethane webbing process and composition, promotes the comprehensive improvement of the anti-slip and wear-resistant properties, mechanical properties, low-temperature mechanical properties, and weather resistance of polyurethane webbing and the polyurethane slings made from it.

[0045] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A high-performance polyurethane sling, characterized in that: It includes a base strip and a polyurethane webbing disposed on the surface of the base strip; the polyurethane webbing is woven from spandex filaments; The spandex filament is prepared from the following components by weight: 100 parts polyurethane prepolymer, 8-12 parts chain extender, 0-1.5 parts initiator, 0-6 parts epoxy resin, 0-0.5 parts organotin catalyst and solvent.

2. The high-performance polyurethane sling according to claim 1, characterized in that: The polyurethane prepolymer is obtained by reacting polymeric polyols and diisocyanates. The polymer polyol is one or a mixture of polycarbonate diol, polytetrahydrofuran ether diol, and polybutylene adipate polyol; The diisocyanate is one or a mixture of isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, 2,4-toluene diisocyanate, and 4,4'-diphenylmethane diisocyanate; In polymer polyols and diisocyanates, the NCO / OH ratio is (3-4):

2.

3. The high-performance polyurethane sling according to claim 1, characterized in that: The chain extender is one or a mixture of 1,4-butanediol, bis(sec-butylamino)diphenylmethane, 3,3′-dichloro-4,4′-diaminodiphenylmethane, allyl alcohol, methyl allyl alcohol, 2,2-di(hydroxymethyl)-1-butene, 1,4-butenediol, and trimethylolpropane diallyl ether.

4. The processing technology of a high-performance polyurethane sling according to any one of claims 1-3, characterized in that: Including the following processes: The prepolymer is mixed with a solvent, and a chain extender, epoxy resin, organotin catalyst, and initiator are added to obtain a spinning solution. Spinning, solidification, and irradiation yield spandex filaments; Weaving yields polyurethane webbing; the polyurethane webbing is then placed on the surface of the base tape to obtain a polyurethane sling.

5. The processing technology of a high-performance polyurethane sling according to claim 4, characterized in that: The prepolymer is obtained by the following process: The polymer polyol is heated to 50-60°C, diisocyanate is added, the temperature is raised to 78-84°C, and the mixture is stirred for 90-120 minutes to obtain the prepolymer.

6. The processing technology of a high-performance polyurethane sling according to claim 4, characterized in that: The spinning solution comprises the following components by weight: 100 parts polyurethane prepolymer, 8-12 parts chain extender, 3-6 parts epoxy resin, 0.5-1.5 parts initiator, 0.1-0.3 parts organotin catalyst, and 300-400 parts solvent.

7. The processing technology of a high-performance polyurethane sling according to claim 6, characterized in that: The epoxy resin is obtained by the following process: In a nitrogen atmosphere, fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene are dissolved in tetrahydrofuran by stirring. A catalyst is added, and the reaction is carried out for 100-150 min to obtain epoxy resin.

8. The processing technology of a high-performance polyurethane sling according to claim 7, characterized in that: The molar ratio of the fluorinated acrylate, cyclohexene, 4-cyclohexene-1,2-dicarboxylic acid diglycidyl ester, and 5-(triethoxysilyl)-2-norbornene is 1:(9-15):(5-11):(4-8).

9. The processing technology of a high-performance polyurethane sling according to claim 7, characterized in that: The fluorinated acrylate is one of allyl trifluoroacetate, ethyl tetrafluoroacrylate, propyl pentafluoroacrylate, and trifluoromethyl methacrylate.

10. The processing technology of a high-performance polyurethane sling according to claim 6, characterized in that: The initiator is one or a mixture of two of the following: a photoinitiator and a photoalkalizing agent.

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