CN111500052B

CN111500052B - Tear-resistant light polyurethane shoe material and preparation method thereof

Info

Publication number: CN111500052B
Application number: CN202010413813.9A
Authority: CN
Inventors: 鲍维江
Original assignee: Putian Sanhai Shoe Material Co ltd
Current assignee: Putian Sanhai Shoe Material Co ltd
Priority date: 2020-05-15
Filing date: 2020-05-15
Publication date: 2022-09-20
Anticipated expiration: 2040-05-15
Also published as: CN111500052A

Abstract

The invention relates to the field of polyurethane materials, and discloses a tear-resistant light polyurethane shoe material and a preparation method thereof. Specifically, polyethylene glycol is used as a dispersing agent to enable the glass fiber short shreds to be split, and a layer of polyethylene glycol is uniformly coated on the surface of the glass fiber short shreds, so that the glass fiber short shreds are uniformly dispersed in the formation of polyester polyol during the preparation of the material A; MDI prepolymer is used as material B; further, graphene oxide and rubber emulsion are subjected to ultrasonic dispersion, and the graphene oxide is reduced by hydrazine hydrate to be combined with rubber particles, so that the formed slurry is coated with the rubber particles by the graphene, and the rubber particles are used as a material C which is used for the foaming shoe materials of the material A and the material B. According to the invention, through the improvement of the stock solution, the polyurethane foaming shoe material keeps good tear resistance and wear resistance while being light, the requirement on equipment is low, the improvement on the existing mature shoe material foaming equipment is not needed, the process is easy to control, and the large-scale popularization and use are easy.

Description

Tear-resistant light polyurethane shoe material and preparation method thereof

Technical Field

The invention relates to the field of polyurethane materials, in particular to a polyurethane material for shoe materials, and further specifically relates to a tear-resistant light polyurethane shoe material and a preparation method thereof.

Background

Polyurethane is a multifunctional and versatile synthetic polymeric material, typically prepared by reacting an oligomeric polyol, a polyisocyanate, and a chain extender/crosslinker. Compared with metal materials, polyurethane has the advantages of light weight, low noise, wear resistance, low processing cost, acid corrosion resistance and the like. Compared with plastics, the high-toughness wear-resistant rubber has the advantages of high toughness, high wear resistance and the like. Compared with common rubber, the polyurethane has the advantages of wear resistance, cutting resistance, tearing resistance, high bearing property, ozone resistance and the like, is simple to manufacture, can be encapsulated and poured, and has wide hardness range. The material can be made into hard foam heat-insulating material, soft foam pad material, elastomer material, microporous elastomer shoe material, high-elastic fiber, fabric and leather coating, adhesive, sealant, etc. due to different raw material selection and reaction forming process. Due to the diversification of product forms and manufacturing processes, the product has wide application fields, and has application in heat preservation, cold chain, traffic, buildings, home furnishing, shoe products, mechanical accessories, sports equipment and the like. Compared with the traditional thermoplastic polymers such as polyethylene, polypropylene, polystyrene, polyvinyl chloride and the like, the thermoplastic polymer has wider application.

The polyurethane shoe material is mainly formed by pouring and molding polyurethane stock solution. Along with the development of social economy and the continuous improvement of living standard of people, the quality of the sole material is continuously improved, and the selectivity is more and more. Most of the traditional soles are made of leather, NR and other natural materials. The polyurethane used as the sole material has the characteristics of light weight, good elasticity, high strength, wear resistance, wearing comfort and the like. As a lightweight sole material, polyurethane has better rebound resilience and wear resistance compared with EVA, and has unique advantages in sports shoes, safety shoes and other articles. The polyurethane is used for shoe materials, and solves the problems that the prior plastic sole and the prior regenerated rubber sole are easy to break and the like and the rubber sole is easy to break. Particularly, the polyurethane pouring mold forming process is more convenient for preparing shoes with various shapes, and the forming process and the appearance design ensure that various safety performances of the shoes are more stable. Such as polyurethane soles, were originally used only for daily wear shoes, with improvements in impact resistance, puncture resistance and slip resistance, extending to work shoes and safety shoes. Polyurethane shoe materials are generally prepared by a reaction Injection molding process, which is also called Reaction Injection Molding (RIM) and is a process for producing a brand new polymer containing a new characteristic group structure at an extremely high speed by metering a substance with low molecular weight in a liquid form, instantly mixing and injecting the substance into a mold, rapidly reacting in the mold cavity, and rapidly increasing the molecular weight of the material through chain extension. Particularly, the polyurethane shoe material can be slightly foamed to be light.

The wear resistance and tear resistance of polyurethane have been excellent in shoe materials, and initially, products thereof were produced at high density(about 0.65 g/cm) ³ Above) the abrasion resistance test can reach more than 100% (NBS test). The abrasion resistance of the rubber exceeds that of the rubber. Because it is environmental friendly and lighter than rubber products, PU shoe material products become a favorite generation in the shoe industry and consumers. With the continuous update of polyurethane technology, the requirements of the market on PU are lighter and more leisure, and the requirements of manufacturers on cost reduction, the original high density of the polyurethane sole is reduced to 0.45g/cm ³ Left and right. The product density is reduced and the cost is reduced, but the problems that the tearing strength is reduced after foaming and lightening, and the wear resistance is reduced from more than 100 percent (NBS) to 30 percent (NBS) at present are caused. With the requirements of people on sports and leisure, the micro-foamed polyurethane soles are preferentially adopted in various sports shoes at present. In order to pursue elastic shock absorption and light weight, microcellular polyurethane soles of microcellular foams become the mainstream of development, microcellular polyurethane elastomers of polyurethane have become an important matching material in the shoe making industry, and important accessories such as soles, heels, toe caps, insoles and the like of many shoes such as golf shoes, baseball shoes, football shoes, ski shoes, sneakers, safety shoes and the like are made of polyurethane. The reduction of density of molded articles while maintaining the excellent physical properties of polyurethane shoe soles is two major requirements in the polyurethane shoe sole market. When the microcellular foamed polyurethane shoe material is pursued to be light in weight, excessive foaming is often pursued, so that the wear resistance of the polyurethane shoe material is reduced, the strength is reduced, particularly the tear resistance is obviously reduced, and the development of sports shoes is extremely unfavorable. How to cooperate the lightening property with the tear resistance and the wear resistance is particularly important for further promoting the development of polyurethane in the field of shoe materials. The key point of product upgrading of the current polyurethane shoe material enterprises is also.

Disclosure of Invention

Aiming at the contradiction that the existing polyurethane applied to sports shoe materials has poor tear resistance and poor wear resistance and the coordination between foaming lightening and tearing resistance is difficult, the invention provides a tear-resistant light polyurethane shoe material. Further, the invention also provides a preparation method of the tear-resistant light polyurethane shoe material.

In order to achieve the above purpose, firstly, a preparation method of the tear-resistant light polyurethane shoe material is provided, which is characterized by comprising the following steps:

s1: uniformly mixing the short glass fiber shreds with polyethylene glycol, and dispersing by a fluidized bed type air flow crusher to obtain modified short glass fiber shreds;

s2: adding adipic acid, ethylene glycol and diethylene glycol into a reaction kettle, uniformly stirring, adding the modified glass fiber short cut filament obtained in the step S1, sealing a cover plate of the reaction kettle, introducing nitrogen, raising the temperature of the reaction kettle to 130 ℃, and keeping the temperature for 2 hours; further heating to 135-140 ℃, and keeping the temperature for 1h; the temperature at the top of the fractionating tower is controlled at 100-102 ℃ through the fractionating tower; continuously heating to 150 ℃ and 200 ℃, and keeping the temperature for 1h; adding tetraisopropyl titanate, and keeping the temperature at 220 ℃ for 1h; then vacuumizing until the reading of a vacuum meter is 0.08MPa, and sampling every 30min until the acid value is less than or equal to 0.5mgKOH/g and the hydroxyl value is 53-59 mgKOH/g; stopping heating, introducing nitrogen to gradually cool, discharging materials and entering a sealed tank to obtain polyester polyol with dispersed glass fiber chopped strands;

s3: uniformly dispersing the polyester polyol of the dispersed glass fiber chopped strands obtained in the step S2, a micromolecule chain extender, a catalyst, a foaming agent and a foam stabilizer to obtain a material A;

s4: under the protection of nitrogen, 4 '-diphenylmethane diisocyanate (MDI) is put into a reaction kettle, the temperature of the reaction kettle is controlled to be 70-75 ℃, reaction control agent octanoic acid is added while slowly stirring, then polyester polyol of the dispersed glass fiber short cut threads obtained in the step S2 is added, stirring reaction is carried out for 1h, liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI) is added, the temperature is controlled to be 60-65 ℃, stirring reaction is carried out for 0.5h, stirring is stopped, the temperature is reduced to 40-50 ℃, aging is carried out for 0.5h, namely, cooling and discharging and packaging are carried out, so that material B is obtained;

s5: adding graphene oxide into rubber emulsion, performing ultrasonic dispersion for 1-3h, heating to 90-95 ℃, adding hydrazine hydrate, continuing ultrasonic treatment for 1-1.5h, and drying to obtain slurry with the solid content of 30-40wt%, wherein the slurry is used as an auxiliary agent C material;

s6: stirring the material A and the material C in a mixing tank at the speed of 100-120rpm for 10-15min, and uniformly mixing, wherein the temperature is maintained at 20-30 ℃; then adding the material B, mixing at high speed for 7-10s at the speed of 1000-2000rpm, uniformly injecting into a metal shoe material mould, foaming and curing at 50-55 ℃ for 5-7min to obtain the tear-resistant light polyurethane shoe material; wherein the material A, the material B and the material C are mixed according to the mass ratio of 12:10: 0.1-0.5.

Preferably, the glass fiber short cut yarn in S1 is provided by Jiacheng fibers of Taian city, and has a fiber diameter of 9-13 μm and a chopped length of 1-3 mm.

Preferably, in S1, the polyethylene glycol is PEG600, which is used as a dispersing agent for the glass fiber chopped strands, and the glass fiber chopped strands are cleaved by supersonic airflow impact in a fluidized bed jet mill, and a layer of polyethylene glycol is uniformly coated on the surface of the glass fiber chopped strands, so as to facilitate uniform dispersion in the later formation of polyester polyol.

Preferably, the glass fiber chopped strands in S1 are mixed with polyethylene glycol in a mass ratio of 100: 2-3, and mixing.

Preferably, in S1, the fluid bed type jet mill is a QLD type fluid bed type jet mill, which mainly uses supersonic jet flow thereof to impact, disperse and split the chopped glass fibers in the milling chamber, and selects a lower classification rotation speed to prevent the chopped glass fibers from being excessively milled and refined, and the chopped glass fibers are timely guided out from the turbine classifier; further preferably, the classification rotation speed is controlled at 200 rpm.

Preferably, the adipic acid, the ethylene glycol, the diethylene glycol, the modified glass fiber chopped strand and the tetraisopropyl titanate in the S2 are as follows according to parts by weight: 50-60 parts of adipic acid, 15-20 parts of ethylene glycol, 15-20 parts of diethylene glycol, 3-5 parts of modified glass fiber chopped strands and 0.005-0.01 part of tetraisopropyl titanate.

Preferably, the polyester polyol of the dispersed glass fiber chopped strands, the small molecule chain extender, the catalyst, the foaming agent and the foam stabilizer in the S3 are as follows according to the weight parts: 70-80 parts of polyester polyol dispersed in glass fiber chopped strands, 5-10 parts of micromolecular chain extender, 1-2 parts of catalyst, 0.1-0.5 part of foaming agent and 0.2-0.3 part of foam stabilizer; further preferably, the small molecular chain extender is at least one of ethylene glycol and glycerol; the catalyst is triethylene diamine; the foaming agent is water; the foam stabilizer is dimethyl siloxane.

Preferably, the 4, 4 '-diphenylmethane diisocyanate (MDI), the polyester polyol of dispersed glass fiber chopped strand described in S4, the liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI), and the caprylic acid are in parts by weight: 50-60 parts of 4, 4 '-diphenylmethane diisocyanate (MDI), 35-45 parts of polyester polyol dispersing glass fiber chopped strands, 3-5 parts of liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI) and 0.005-0.01 part of caprylic acid.

Preferably, the mass ratio of the graphene oxide to the rubber emulsion in S5 is 1: 100-200; the rubber emulsion is one of styrene-butadiene rubber emulsion, isoprene rubber emulsion, butyl-acrylic rubber emulsion and butyl rubber emulsion. The rubber emulsion contains nano-scale colloidal particles and has a solid content of 5-8%; further preferably, the rubber emulsion is an intermediate product matured in the rubber synthesis industry, the rubber emulsion is a dispersion liquid of rubber particles, the rubber particles are excellent in elasticity after being dried, the rubber particles in the rubber emulsion are dispersed by nano-scale colloidal particles, and when graphene oxide is added into the rubber emulsion for ultrasonic dispersion, the graphene oxide is very easily attached to the rubber particles due to the fact that the graphene oxide is nano-scale, further, the graphene oxide is reduced into graphene under the heating condition by adding hydrazine hydrate, so that the formed slurry is used as a material C, when the material C is used for the foamed shoe materials of the material A and the material B, the rubber particles are good in elasticity and toughness, the graphene is excellent in wear resistance, and the graphene coated rubber particles are beneficial to increasing the toughness and wear resistance of the shoe materials.

Preferably, the ultrasonic dispersion in S5 is processed using an ultrasonic disperser with a probe frequency of 20kHz and a power of 1200W.

Preferably, the addition amount of the hydrazine hydrate in S5 is 10-15% of the mass of the graphene oxide.

The invention also provides a tear-resistant light polyurethane shoe material prepared by the method. Polyurethane is an excellent shoe material, and has good elasticity, light weight and easy molding characteristics. The shoe material can be foamed and molded in a mold by preparing a proper stock solution. In the currently applied and concentrated polyurethane sports shoes, as a key material of soles, polyurethane foam is required to have good tear resistance, wear resistance and light weight after being molded. When developing a polyester polyurethane foam shoe material, a way of enlarging foam is often adopted in order to reduce cost and obtain a lighter shoe material. However, the obtained lightweight shoe material has greatly reduced tearing resistance and abrasion resistance due to excessive foaming. Based on the technical problem, the invention ensures light foaming and improves the tear resistance and wear resistance of the shoe material. In order to realize the purpose, when preparing a material A, the invention carries out split treatment on the glass fiber short shreds, the glass fiber short shreds are split by using polyethylene glycol as a dispersing agent, and a layer of polyethylene glycol is uniformly coated on the surface of the glass fiber short shreds, so that the glass fiber short shreds are uniformly dispersed in the formation of polyester polyol when preparing the material A, and the uniformly dispersed glass fiber short shreds are dispersed in a shoe material when foaming the shoe material by a mould, thereby endowing the shoe material with good toughness and tear resistance; further, graphene oxide and rubber emulsion are subjected to ultrasonic dispersion, and the graphene oxide is reduced by hydrazine hydrate to be combined with the rubber particles, so that the formed slurry contains graphene coated rubber particles which serve as a material C, and when the material C is used for the foamed shoe materials of the material A and the material B, the graphene coated rubber particles are beneficial to increasing the toughness and the wear resistance of the shoe materials.

Compared with the prior art, the invention has the following excellent effects:

1. according to the invention, when the material A is prepared, the chopped glass fiber strands are split and dispersed, the chopped glass fiber strands are split by using polyethylene glycol as a dispersing agent, and a layer of polyethylene glycol is uniformly coated on the surface of the chopped glass fiber strands, so that the chopped glass fiber strands are uniformly dispersed in the formation of polyester polyol when the material A is prepared, and the uniformly dispersed chopped glass fiber strands are dispersed in a shoe material when the shoe material is foamed by a mold, so that the shoe material is endowed with good toughness and tear resistance.

2. According to the invention, graphene oxide and rubber emulsion are subjected to ultrasonic dispersion, and the graphene oxide is reduced by hydrazine hydrate to be combined with rubber particles, so that the graphene coated rubber particles in the formed slurry are used as a material C, and when the material C is used for foamed shoe materials of the material A and the material B, the graphene coated rubber particles are beneficial to increasing the toughness and the wear resistance of the shoe materials.

3. According to the invention, through the improvement of the stock solution, the polyurethane foaming shoe material keeps good tear resistance and wear resistance while being light, the requirement on equipment is low, the improvement on the existing mature shoe material foaming equipment is not needed, the existing mature equipment is adopted for preparation, the process is easy to control, and the large-scale popularization and use are easy.

Drawings

The invention is further described below with reference to the accompanying drawings:

FIG. 1 is a flow chart of a preparation process of the tear-resistant lightweight polyurethane shoe material.

Detailed Description

The present invention is further illustrated by the following examples, which are presently preferred and illustrative, but are not intended to limit the scope of the invention.

Example 1

Selecting short glass fiber shreds provided by Jiacheng fiber Co Ltd of Tai' an city, wherein the fiber diameter is 9-13 μm, the chopped length is 1-3mm, and the short glass fiber shreds are mixed with polyethylene glycol (PEG600) according to the mass ratio of 100: 3 adding the mixture into a high-speed mixer to be uniformly mixed; then sending the glass fiber short shreds into a QLD type fluidized bed type air flow grinder (QLD680 type, provided by Shanghai brocade chemical equipment Co., Ltd.), controlling the grading rotation speed at 200rpm (the maximum grading rotation speed of the equipment reaches 4000rpm, the larger the grading rotation speed is, the finer the granularity of the obtained material is), dispersing and splitting the impact of the glass fiber short shreds in a grinding chamber by using supersonic jet flow of the equipment, selecting a lower grading rotation speed for preventing the glass fiber short shreds from being excessively ground and refined to damage fibers, and timely leading the glass fiber short shreds with the split fibers out of a turbine classifier; polyethylene glycol PEG600 as dispersant for the glass fiber chopped strands is subjected to supersonic airflow impact in a fluidized bed airflow pulverizer to enable the glass fiber chopped strands to be split, and a layer of polyethylene glycol is uniformly coated on the surfaces of the glass fiber chopped strands to obtain the modified glass fiber chopped strands.

Example 2

Adding 14kg of adipic acid, 5kg of ethylene glycol and 5kg of diethylene glycol into a reaction kettle, uniformly stirring, then adding 1kg of the modified glass fiber chopped strand obtained in the example 1, sealing a cover plate of the reaction kettle, introducing nitrogen, raising the temperature of the reaction kettle to 130 ℃, and keeping the temperature for 2 hours; further heating to 135 ℃, and keeping the temperature for 1h; the temperature at the top of the fractionating tower is controlled at 100-102 ℃ through the fractionating tower; continuously heating to 200 ℃, and keeping the temperature for 1h; adding 0.002kg of tetraisopropyl titanate, and keeping the temperature at 220 ℃ for 1h; then vacuumizing until the reading of a vacuum meter is 0.08MPa, and sampling every 30min until the acid value is less than or equal to 0.5mgKOH/g and the hydroxyl value is 53-59 mgKOH/g; stopping heating, introducing nitrogen to gradually cool, discharging materials and entering a sealed tank to obtain polyester polyol with dispersed glass fiber chopped strands;

8kg of polyester polyol of the obtained dispersed glass fiber chopped strands, 1kg of micromolecular chain extender ethylene glycol, 0.2kg of catalyst triethylene diamine, 0.04kg of foaming agent water and 0.02kg of foam stabilizer dimethyl siloxane are uniformly dispersed to obtain material A.

Example 3

Under the protection of nitrogen, 15kg of 4, 4 '-diphenylmethane diisocyanate (MDI) is put into a reaction kettle, the temperature of the reaction kettle is controlled to be 70-75 ℃, 0.002kg of reaction control agent octanoic acid is added while slowly stirring, then 10kg of polyester polyol of the dispersed glass fiber short-cut filaments obtained in the example 2 is added, stirring reaction is carried out for 1h, 1kg of liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI) is added, the temperature is controlled to be 60-65 ℃, stirring reaction is carried out for 0.5h, stirring is stopped, the temperature is reduced to 40-50 ℃, aging is carried out for 0.5h, namely, the temperature is reduced, discharging and packaging are carried out, thus obtaining the material B.

Example 4

Mixing graphene oxide and rubber emulsion in a mass ratio of 1: 100, mixing; the rubber emulsion is styrene-butadiene rubber emulsion containing nano-scale colloidal particles and having a solid content of 8%, and is subjected to ultrasonic dispersion for 2 hours, the ultrasonic dispersion is processed by an ultrasonic dispersion instrument with a probe frequency of 20kHz and a power of 1200W, then the temperature is raised to 95 ℃, hydrazine hydrate is added, the addition amount of the hydrazine hydrate is 15% of the mass of the graphene oxide, ultrasonic treatment is continued for 1 hour, and the slurry is dried until the solid content is 40wt% and is used as an auxiliary agent C material.

Example 5

Stirring the material A of the example 2 and the material C of the example 4 in a batching tank at 100rpm for 10min, and uniformly mixing, wherein the temperature is maintained at 20-30 ℃; then adding the material B of the embodiment 3, mixing at a high speed of 1000rpm for 7s, quickly and uniformly injecting into a metal shoe material mold, foaming and curing at 50-55 ℃ for 5min, opening the mold, releasing the shoe material, standing at room temperature and curing for 24h to obtain the tear-resistant light polyurethane shoe material; wherein the material A, the material B and the material C are mixed according to the mass ratio of 12:10: 0.3.

Comparative example 1

Mixing the material A of the example 2 and the material B of the example 3 at 1000rpm for 7s at high speed; wherein the material A and the material B are mixed according to the mass ratio of 12: 10; quickly and uniformly injecting the mixture into a metal shoe material mold, foaming and curing the mixture for 5min at the temperature of 50-55 ℃, opening the mold, removing the shoe material, standing and curing the mixture for 24h at room temperature to obtain the tear-resistant light polyurethane shoe material.

Comparative example 2

Mixing graphene and rubber emulsion in a mass ratio of 1: 100, mixing; the rubber emulsion is styrene-butadiene rubber emulsion containing nano-scale colloidal particles and having a solid content of 8%, and is subjected to ultrasonic dispersion for 2 hours, wherein the ultrasonic dispersion is processed by using an ultrasonic dispersion instrument with a probe frequency of 20kHz and a power of 1200W, and then the temperature is raised to 95 ℃, and the rubber emulsion is dried to obtain slurry with a solid content of 40wt%, and the slurry is used as an auxiliary agent C material.

Stirring the material A and the material C of the example 2 in a batching tank at 100rpm for 10min, and uniformly mixing, wherein the temperature is maintained at 20-30 ℃; then adding the material B of the embodiment 3, mixing at a high speed of 1000rpm for 7s, quickly and uniformly injecting the mixture into a metal shoe material mold, foaming and curing at 50-55 ℃ for 5min, opening the mold, releasing the shoe material, standing and curing at room temperature for 24h to obtain a tear-resistant light polyurethane shoe material; wherein the material A, the material B and the material C are mixed according to the mass ratio of 12:10: 0.3.

Comparative example 3

No polyethylene glycol was added during the treatment of the glass staple fibers in example 1, and the remaining preparation and starting materials were used in accordance with examples 2 to 5.

Comparative example 4

No treated staple glass fibers were added to the polyester polyol prepared in example 2, no adjuvant C material was added in example 5, and the rest of the process and raw material application were identical to those of examples 2-5.

To simulate the use of the shoe material and the qualitative comparative analysis of the properties, the molds of example 5 and comparative examples 1 to 3 produced sheets with a thickness of 6mm, and the relevant properties were tested as follows:

1. testing the molding density:

the density was measured by test method A with reference to GB/T533-.

2. And (3) testing tensile strength:

with reference to GB/T6344-2008 "determination of tensile Strength and elongation at Break of Flexible foamed Polymer Material", at least 5 dumbbell-shaped test pieces were cut out with a prototype at a tensile rate of 500. + -.50 mm/mm, and the tensile strength and elongation tested are shown in Table 1.

3. Tear strength:

according to GB/T10808-2006 'determination of tearing strength of high polymer porous elastic material', a sample is cut from a central part, a sample with uniform foam holes is selected, a notch with the length of 40mm is cut at one end, and the length direction of the notch is vertical to the rising direction of the foam holes; the sample is opened, clamped on a clamp of the instrument and loaded at the speed of 50 mm/min; the maximum force at which the specimen breaks by 25mm is recorded. The maximum tensile value, T, per sample thickness, d, gives the tear strength, as shown in Table 1.

4. NBS abrasion resistance:

partially referring to ASTM-D1630-2006 Standard test method for rubber wear resistance, a Standard rubber test piece with Shore A of 65 is taken, fixed in a test piece seat on a NBS (NBS wear machine) force arm by using double faced adhesive tape, and a force arm is put down to enable the Standard rubber test piece to contact No. 40 special wear-resistant abrasive paper on a NBS wear machine roller. And starting pre-grinding until the radian presented by the abrasion of the standard rubber test piece is matched with the bending of the abrasive paper. The counting of the NBS abrasion machine is reset to zero, standard sample grinding is carried out until the abrasion thickness reaches 2.5mm, and the testing revolution R1 is recorded; taking down a standard rubber test piece, replacing a test sample piece with a shoe material test piece of 25.4 multiplied by 25.4mm, repeatedly testing, and recording the test revolution R; (ii) a The standard rubber test piece before the test piece was replaced was removed and the number of test revolutions R2 was recorded. NBS abrasion resistance was 2R/(R1+ R2). The key parameters of the test are as follows: diameter of the rotating wheel: diameter 150mm (outer diameter); loading: 2265g three groups; rotating shaft speed: 45 plus or minus 5 rpm; abrasive paper granularity of 40 #. The test results are shown in table 1.

Table 1:

according to the tests, when the material A is prepared, the chopped glass fiber strands are split and dispersed, the chopped glass fiber strands are split by using polyethylene glycol as a dispersing agent, and a layer of polyethylene glycol is uniformly coated on the surfaces of the chopped glass fiber strands, so that the shoe material has good toughness and tear resistance. The graphene oxide and the rubber emulsion are subjected to ultrasonic dispersion, and the graphene oxide is reduced by hydrazine hydrate to be combined with the rubber particles, so that the graphene coated rubber particles in the formed slurry are used as a material C, and when the material C is used for foaming shoe materials of the material A and the material B, the graphene coated rubber particles are beneficial to increasing the tearing strength and the wear resistance of the shoe materials. Comparative example 1 no additive C was added, and the obtained shoe material was poor in toughness and wear resistance due to the absence of graphene-coated rubber particles. The comparative example 2 adopts the conventional method of directly adding graphene without adopting the method of reducing graphene oxide and compounding the graphene oxide with colloidal particles, so that the graphene is used as a nano filler and has poor dispersibility with a polyurethane system, thereby influencing the improvement of tearing property and wear resistance. Comparative example 3 because the glass chopped strands were not treated with polyethylene glycol, the dispersibility of the glass chopped strands was affected during the preparation of polyester polyol, and it was difficult to form a stable compatible phase with polyester polyol, resulting in limitation of glass fibers in the aspect of toughening and abrasion resistance improvement of shoe materials. In comparative example 4, the toughness and wear resistance of the obtained shoe material were greatly reduced because no glass fiber chopped strands and no graphene-coated rubber particles were added.

It is to be understood that the exemplary embodiments described herein are to be considered as illustrative and not restrictive. Moreover, descriptions of features or aspects in various embodiments should be applicable to other similar features or aspects in other embodiments.

While one or more embodiments of the present invention have been illustrated in the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.

Claims

1. A preparation method of a tear-resistant light polyurethane shoe material is characterized by comprising the following specific steps:

s2: adding adipic acid, ethylene glycol and diethylene glycol into a reaction kettle, uniformly stirring, adding the modified glass fiber short cut filament obtained in the step S1, sealing a cover plate of the reaction kettle, introducing nitrogen, raising the temperature of the reaction kettle to 130 ℃, and keeping the temperature for 2 hours; further heating to 135-140 ℃, and keeping the temperature for 1h; the temperature at the top of the fractionating tower is controlled at 100-102 ℃ through the fractionating tower; continuously heating to 150 ℃ and 200 ℃, keeping the temperature for 1h, adding tetraisopropyl titanate, and keeping the temperature for 1h at 220 ℃; then vacuumizing until the reading of a vacuum meter is 0.08MPa, and sampling every 30min until the acid value is less than or equal to 0.5mgKOH/g and the hydroxyl value is 53-59 mgKOH/g; stopping heating, introducing nitrogen to gradually cool, discharging materials and entering a sealed tank to obtain polyester polyol with dispersed glass fiber chopped strands;

s5: adding graphene oxide into rubber emulsion, performing ultrasonic dispersion for 1-3h, heating to 90-95 ℃, adding hydrazine hydrate, continuing ultrasonic treatment for 1-1.5h, and drying to obtain slurry with the solid content of 30-40wt%, wherein the slurry is used as an auxiliary agent C material; the mass ratio of the graphene oxide to the rubber emulsion is 1: 100-; the rubber emulsion is one of styrene-butadiene rubber emulsion, isoprene rubber emulsion, butyl-acrylic rubber emulsion and butyl rubber emulsion; the rubber emulsion contains nano-scale colloidal particles and has a solid content of 5-8%;

2. The method for preparing the tear-resistant light polyurethane shoe material according to claim 1, wherein the method comprises the following steps: the glass fiber short cut filament in S1 is provided by Jiacheng fiber of Taian city, the fiber diameter of the glass fiber short cut filament is 9-13 μm, and the chopped length is 1-3 mm; the polyethylene glycol is PEG 600.

3. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: and (3) in S1, mixing the glass fiber chopped strands with polyethylene glycol according to a mass ratio of 100: 2-3, and mixing.

4. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: in S1, the fluid bed type jet mill is a QLD type fluid bed type jet mill, and the classification rotational speed is controlled at 200 rpm.

5. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: in the S2, the adipic acid, the ethylene glycol, the diethylene glycol, the modified glass fiber chopped strands and the tetraisopropyl titanate are as follows in parts by weight: 50-60 parts of adipic acid, 15-20 parts of ethylene glycol, 15-20 parts of diethylene glycol, 3-5 parts of modified glass fiber chopped strands and 0.005-0.01 part of tetraisopropyl titanate.

6. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: the polyester polyol, the micromolecular chain extender, the catalyst, the foaming agent and the foam stabilizer which are used for dispersing the glass fiber chopped strands in the S3 are as follows according to the parts by weight: 70-80 parts of polyester polyol dispersed in glass fiber chopped strands, 5-10 parts of micromolecular chain extender, 1-2 parts of catalyst, 0.1-0.5 part of foaming agent and 0.2-0.3 part of foam stabilizer; wherein: the micromolecular chain extender is at least one of ethylene glycol and glycerol; the catalyst is triethylene diamine; the foaming agent is water; the foam stabilizer is dimethyl siloxane.

7. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: the 4, 4 '-diphenylmethane diisocyanate (MDI), the polyester polyol of the dispersed glass fiber chopped strand, the liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI) and the caprylic acid in the S4 are calculated according to the following weight portions: 50-60 parts of 4, 4 '-diphenylmethane diisocyanate (MDI), 35-45 parts of polyester polyol dispersing glass fiber chopped strands, 3-5 parts of liquefied 4, 4' -diphenylmethane diisocyanate (liquefied MDI) and 0.005-0.01 part of caprylic acid.

8. The method for preparing the tear-resistant light-weight polyurethane shoe material according to claim 1, wherein the method comprises the following steps: in S5, the ultrasonic dispersion is processed by an ultrasonic dispersion instrument with the probe frequency of 20kHz and the power of 1200W; the addition amount of the hydrazine hydrate is 10-15% of the mass of the graphene oxide.

9. A tear resistant lightweight polyurethane footwear produced by the method of any one of claims 1 to 8.