High-wear-resistance silicon PU composite layer, preparation method thereof and application of high-wear-resistance silicon PU composite layer in preparation of ball field surface layer

Abstract

The invention discloses a high-wear-resistance silicon PU (polyurethane) composite layer, a preparation method thereof and application of the high-wear-resistance silicon PU composite layer in a ball field surface layer, and particularly belongs to the technical field of organic silicon modified polyurethane. The composite layer adopts a three-layer structural design and comprises a closed priming coat, an elastic wear-resistant layer and a functional finishing coat from bottom to top; according to the elastic wear-resistant layer, modified Si3N4 / graphene composite powder, hydroxyl-terminated polybutadiene and siloxane in a component A are mixed with a component B of an isocyanate prepolymer according to the mass ratio of 1: 1.1-1.2, and the wear resistance and rebound resilience are remarkably improved; nano-zirconia dispersion liquid is introduced into the functional finishing coat to cooperate with a specific polyurethane system, so that the ageing resistance and the surface hardness are enhanced; according to the closed bottom coating, epoxy silane oligomer is used as a main body to reinforce the adhesive force of a base surface, and the composite layer has excellent wear resistance, mechanical property, aging resistance and rebound resilience.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicone-modified polyurethane, and particularly relates to a high-wear-resistance silicone PU composite layer, a preparation method thereof and application thereof in preparing a court surface layer. BACKGROUND

[0002] With the popularization of national fitness, the demand for high-performance sports courts is increasing. High-quality courts need to consider the friction coefficient, impact protection, logo clarity and weather resistance.

[0003] The main court surface materials at present mainly include: acrylic court: the water-based system has bright colors and good weather resistance, but is strict in the requirement for the flatness of the foundation, and the 2mm thin layer structure leads to a service life of about 4 years; EPDM ground: the environment-friendly rubber buffer layer (about 6mm thick) saves the foundation cost, but has limited elastic recovery performance; silicone PU court: directly constructed on the asphalt / concrete base surface, and has the advantages of energy absorption and shock absorption and wear resistance, and becomes an ideal choice.

[0004] However, the existing silicone PU material has significant defects: most of them are single / dual-component high-filled polyurethane systems, and uneven dispersion of fillers leads to surface powdering after outdoor use for 3-5 years, which not only shortens the service life, but also increases the risk of joint injury of the exerciser due to insufficient rebound rate (generally <60%). Especially, the mechanical strength of the conventional filler system decays by more than 30% after ultraviolet aging, and it is difficult to meet the durability requirements of high-frequency use scenarios. Therefore, it is urgent to develop a silicone PU composite structure with high rebound elasticity, long-term wear resistance and anti-aging performance. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a silicone PU composite layer with high rebound elasticity, long-term wear resistance and anti-aging performance.

[0006] In order to achieve the above-mentioned purpose, the following technical solutions are disclosed:

[0007] In a first aspect, the present application provides a high-wear-resistance silicone PU composite layer, which comprises, from bottom to top, a closed primer layer, an elastic wear-resistant layer and a functional cover layer, the closed primer layer is coated by a closed primer layer material, the elastic wear-resistant layer is coated by an elastic wear-resistant layer material, and the functional cover layer is coated by a functional cover layer material;

[0008] The functional cover layer material contains the following components in mass fraction:

[0009] 45-50 parts of polypropylene glycol, 50-55 parts of 4,4-diphenyl methane diisocyanate, 15-20 parts of 2,2-dimethylol propionic acid, 40-50 parts of nano zirconium oxide dispersion, 0.5-1.5 parts of leveling agent, 0.1-0.3 parts of defoaming agent, and 0.5-0.7 parts of antioxidant.

[0010] The elastic wear-resistant layer material is mixed by component A and component B in a mass ratio of 1:(1.1-1.2);

[0011] The component A contains components in mass fractions of 30-40 parts of polypropylene glycol, 10-20 parts of hydroxyl-terminated polybutadiene, 10-15 parts of hydroxyl-terminated polydimethylsiloxane, 25-40 parts of heavy calcium carbonate, 2-5 parts of modified Si3N4 / graphene composite powder, 0.5-1.5 parts of wetting agent, 0.3-0.8 parts of defoaming agent, 0.1-0.5 parts of leveling agent, 0.01-0.05 parts of dibutyltin dilaurate, 0.2-0.5 parts of antioxidant, and 0.4-0.7 parts of UV absorber;

[0012] The component B contains components in mass fractions of 60-70 parts of 4,4-diphenyl methane diisocyanate, 25-30 parts of polypropylene glycol, and 0.1 parts of antioxidant;

[0013] The closed primer layer material contains the following components in mass fractions:

[0014] 90-110 parts of epoxy silane oligomer, 2-3 parts of wetting agent, 0.1-0.3 parts of defoaming agent, 0.5-0.7 parts of antioxidant, and 45-55 parts of deionized water.

[0015] Preferably, the leveling agent is a double-end hydroxypropyl silicone oil.

[0016] Preferably, the defoaming agent is a modified polysiloxane copolymer.

[0017] Preferably, the antioxidant is antioxidant 1010.

[0018] Preferably, the wetting agent is an alkyl phenol polyoxyethylene ether.

[0019] Preferably, the UV absorber is Tinuvin 326.

[0020] Preferably, the average particle size of zirconium oxide in the nano-zirconium oxide dispersion is 30 nm, and the solid content is 20-40%.

[0021] Preferably, the number average molecular weight of the polypropylene glycol is 2700-3300, and the hydroxyl value is 0.60-0.75 mmol / g.

[0022] Preferably, the number average molecular weight of the hydroxyl-terminated polybutadiene is 3300-4100, and the hydroxyl value is 0.54-0.64 mmol / g.

[0023] Preferably, the preparation method of the modified Si3N4 / graphene composite powder comprises the following steps:

[0024] S1.1. Si3N4 and graphene oxide with a mass ratio of 9:1 were added to anhydrous ethanol, with a mass ratio of 1:40, and 0.1% of Tween-80 was added, 600W ultrasonic for 30min, to form a uniform suspension;

[0025] S1.2. Under the condition of 30℃, 500r / min stirring, 2-3% of KH-560 of Si3N4 and graphene oxide composite powder was added dropwise, the pH of the system was adjusted to 3.5-4.0, and the ultrasonic was continued for 15min, then the temperature was increased to 120℃ and reacted for 4h, after cooling, centrifuged at 8000r / min for 10min, the supernatant was discarded and the solid precipitate was collected, dried and sieved to obtain modified Si3N4 / graphene composite powder.

[0026] Further preferably, the Si3N4 is spherical particles with an average particle size of 1-3μm.

[0027] Preferably, the preparation method of component A comprises the following steps:

[0028] S2.1. Polypropylene glycol and hydroxyl-terminated polybutadiene were placed in a reaction stirred tank, vacuum dehydrated at 120℃, -0.095MPa for 2h, after dehydration, the temperature was lowered to 70℃, and wetting agent, part of the defoaming agent, heavy calcium carbonate and modified Si3N4 / graphene composite powder were added in turn, the stirring speed was increased to 1000r / min, and the stirring was continued for 50-60min to fully wet and disperse;

[0029] S2.2. Hydroxyl-terminated polydimethylsiloxane was added to the dispersed slurry, and the stirring was continued at 500r / min, -0.08MPa, 80℃ for 2-4h, after the reaction was completed, the temperature was lowered to 50-60℃, the remaining defoaming agent, leveling agent, dibutyltin dilaurate, UV absorber and antioxidant were added, and the stirring was continued at a speed of 200-400r / min for 30-60min, and the dispersion was uniform, and the material was discharged to obtain component A.

[0030] Preferably, the preparation method of component B comprises the following steps:

[0031] In a nitrogen-protected reaction kettle, polypropylene glycol was added, and 4,4-diphenyl methane diisocyanate was added dropwise at 300r / min, 1h was completed, after the dropwise addition was completed, the temperature was increased to 85℃ and reacted for 3h, the temperature was lowered to 40℃, the antioxidant was added, and the stirring was continued for 20min, and the material was discharged to obtain component B.

[0032] Preferably, the preparation method of the sealing primer material comprises the following steps:

[0033] S3.1. Put the epoxy silane oligomer into the stirred kettle, pre-disperse for 5 min at 500-600 r / min, add the wetting agent, defoaming agent, antioxidant in sequence, continue to stir for 5 min;

[0034] S3.2. Add deionized water at a rotation speed of 300-400 r / min, heat to 35-40℃, keep stirring for 30 min, filter the material through a 200-mesh filter screen, and obtain the closed primer material.

[0035] Preferably, the preparation method of the functional finish layer material comprises the following steps:

[0036] S4.1. Put the polypropylene glycol and 2,2-dimethylol propionic acid into the reaction kettle, stir uniformly at 110℃ and 300-500 r / min, cool to 80℃, add 4,4-diphenyl methane diisocyanate, react for 3-4 h under nitrogen atmosphere, cool to 35-40℃ after the reaction is completed, and add the double-end hydroxypropyl silicone leveling agent, modified polysiloxane copolymer defoaming agent, antioxidant in sequence under the condition of 1000-1500 r / min stirring, continue to stir for 25 min;

[0037] S4.2. Slowly add the nano zirconium oxide dispersion liquid, increase the rotation speed to 1500-2000 r / min, high-speed disperse for 20-30 min, cool to 25-30℃, filter the material through a 200-mesh filter screen, and obtain the functional finish layer material.

[0038] In the second aspect, the application provides an application of the high-wear-resistance silicon PU composite layer in preparing a court surface layer.

[0039] In the third aspect, the application provides a preparation method of the high-wear-resistance silicon PU composite layer, and the preparation method comprises the following steps:

[0040] S5.1. Polish and remove dust from the concrete base surface, brush the closed primer material, and the amount is 0.08-0.12 kg / m 2 , dry for 3 h at 25-28℃, and obtain the closed primer;

[0041] S5.2. Mix component A and component B according to the mass ratio of 1:(1.1-1.2), after mixing, scrape and coat on the dried closed primer, the thickness is 6-8 mm, and cure for 6-8 h at 25-28℃, and obtain the elastic wear-resistant layer;

[0042] S5.3. Coat the functional finish layer material on the elastic wear-resistant layer, the coating thickness is 0.3-0.5 mm, and cure for 24 h at 25-28℃, and obtain the functional finish layer, that is, the high-wear-resistance silicon PU composite layer.

[0043] The beneficial effects of the present application are as follows:

[0044] The modified Si3N4 / graphene composite powder in the elastic wear-resistant layer provided by the present application improves the overall wear resistance, mechanical properties and aging resistance of the composite material through the synergistic effect of hard particles and sheet slip, in combination with the nano-zirconium oxide dispersion liquid of the functional cover layer, and the introduction of hydroxyl-terminated polybutadiene in the synthesis of the silicon PU enhances the flexibility of the molecular chain and improves the elasticity of the material. DETAILED DESCRIPTION

[0045] The technical solutions of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0046] In order to further illustrate the present application, the following embodiments are described in detail. The raw materials used in the following embodiments and comparative examples of the present application are all commercially available; the following listed raw material companies are one of the ways to purchase the raw materials.

[0047] In the present application:

[0048] Nano-zirconium oxide dispersion liquid: solid content 20-40%, average particle size of zirconium oxide 30 nm, purchased from Zhejiang Zhitian Micro New Material Co., Ltd.;

[0049] Leveling agent: double-end hydroxypropyl silicone oil, model IOTA-2030-30, purchased from Anhui Aiyouta Silicone Co., Ltd.;

[0050] Defoaming agent: modified polysiloxane copolymer, model IOTA-4100, purchased from Anhui Aiyouta Silicone Co., Ltd.;

[0051] Epoxy silane oligomer: purchased from Guangzhou Aikop New Material Co., Ltd.;

[0052] Wetting agent: alkyl phenol polyoxyethylene ether, purchased from Xingtai Xinlanxing Technology Co., Ltd.;

[0053] Antioxidant: antioxidant 1010, purchased from Tianjin Lisheng Chemical Co., Ltd.;

[0054] UV absorber: Tinuvin 326, purchased from BASF;

[0055] Polypropylene glycol: number average molecular weight 2700-3300, hydroxyl value 0.60-0.75 mmol / g, purchased from Nantong Yixun Chemical Co., Ltd.;

[0056] Hydroxyl-terminated polybutadiene: number average molecular weight 3300-4100, hydroxyl value 0.54-0.64 mmol / g, purchased from Tianyuan Aviation Material Science and Technology;

[0057] Heavy calcium carbonate: purchased from Xufeng Powder;

[0058] Si3N4: silicon nitride, spherical particles, average particle size 1-3 μm, purchased from Ningbo Luofei Nanometer Science and Technology Co., Ltd.;

[0059] Graphene oxide: purchased from Beijing Deke Daojin Technology Co., Ltd.;

[0060] 4,4-Diphenyl methane diisocyanate: purchased from Shanghai Yanze Chemical Co., Ltd.;

[0061] 2,2-Dimethylol propionic acid: purchased from Shanghai Yanze Chemical Co., Ltd.

[0062] Example 1

[0063] Preparation of functional finish material

[0064] S1-1. Take the mass parts of raw materials: 45-50 parts of polypropylene glycol, 50-55 parts of 4,4-diphenyl methane diisocyanate, 15-20 parts of 2,2-dimethylol propionic acid, 40-50 parts of nano zirconium oxide dispersion, 0.5-1.5 parts of leveling agent, 0.1-0.3 parts of defoaming agent, 0.5-0.7 parts of antioxidant;

[0065] S1-2. Put the polypropylene glycol and 2,2-dimethylol propionic acid into the reaction kettle, stir uniformly at 110°C, 300-500 r / min, cool to 80°C, add 4,4-diphenyl methane diisocyanate, react for 3-4 h under nitrogen atmosphere, cool to 35-40°C after the reaction is completed, and then add double-end hydroxypropyl silicone leveling agent, modified polysiloxane copolymer and antioxidant in turn under the condition of 1000-1500 r / min stirring, continue to stir for 25 min;

[0066] S1-3. Slowly add the nano zirconium oxide dispersion, increase the speed to 1500-2000 r / min, high-speed dispersion for 20-30 min, cool to 25-30°C, filter the material through a 200 mesh screen to obtain the functional finish material.

[0067] Preparation of closed primer material

[0068] S2-1. Take the mass parts of raw materials: 100 parts of epoxy silane oligomer, 2-3 parts of wetting agent, 0.1-0.3 parts of defoaming agent, 0.5-0.7 parts of antioxidant, 50 parts of deionized water;

[0069] S2-2. Put the epoxy silane oligomer into the stirred kettle at 20-30°C, pre-disperse for 5 min at 500-600 r / min, add the wetting agent, defoaming agent and antioxidant in sequence, continue to stir for 5 min;

[0070] S2-3. Slowly add deionized water at 300-400 r / min, complete the addition within 10-15 min to avoid local gelation, increase the temperature to 35-40°C, keep stirring for 30 min to make the system fully hydrolyze and homogenize, filter the material through a 200-mesh filter screen to obtain the closed primer material.

[0071] Preparation of modified Si3N4 / graphene composite powder

[0072] S3-1. Add 90 parts of Si3N4 and 10 parts of graphene oxide to 400 parts of anhydrous ethanol, then add 0.5 parts of Tween-80, and ultrasonicate at 600 W for 30 min to form a uniform suspension;

[0073] S3-2. Under stirring at 30°C and 500 r / min, add 2-3 parts of KH-560 (2-3% of the total mass of the powder), adjust the pH to 3.5-4.0 with glacial acetic acid, and continue to ultrasonicate for 15 min to make the coupling agent fully hydrolyze and condense with the surface hydroxyl groups of Si3N4 and graphene;

[0074] S3-3. Transfer the suspension into a reaction kettle, keep the temperature at 120°C for 4 h, centrifuge at 8000 r / min for 10 min after cooling, discard the supernatant and collect the precipitate, wash with anhydrous ethanol for 3 times to remove free silane, vacuum dry at 60°C for 12 h, and pass through a 400-mesh screen to obtain the modified Si3N4 / graphene composite powder.

[0075] Preparation of elastic wear-resistant layer material

[0076] 1 Component A

[0077] S3-1. Weigh the raw materials: 30-40 parts of polypropylene glycol, 10-20 parts of hydroxyl-terminated polybutadiene, 10-15 parts of hydroxyl-terminated polydimethylsiloxane, 25-40 parts of heavy calcium carbonate, 2-5 parts of modified Si3N4 / graphene composite powder, 0.5-1.5 parts of wetting agent, 0.3-0.8 parts of defoaming agent, 0.1-0.5 parts of leveling agent, 0.01-0.05 parts of dibutyltin dilaurate, 0.2-0.5 parts of antioxidant, and 0.4-0.7 parts of UV absorber.

[0078] S3-2. Put the polypropylene glycol and the hydroxyl-terminated polybutadiene into a reaction stirring kettle, dehydrate at 120℃ and -0.095MPa for 2h, after dehydration, cool down to 70℃, add the wetting agent, part of the defoaming agent, heavy calcium carbonate and modified Si3N4 / graphene composite powder in sequence, increase the rotation speed to 1000r / min, continuously stir for 50-60min, fully wet and disperse;

[0079] S3-3. Add the hydroxyl-terminated polydimethylsiloxane into the dispersed slurry, continuously stir at 500r / min, -0.08MPa and 80℃ for 2-4h, after the reaction is completed, cool down to 50-60℃, add the remaining defoaming agent, leveling agent, dibutyltin dilaurate, UV absorber and antioxidant, stir at 200-400r / min for 30-60min, uniformly disperse and discharge, to obtain component A.

[0080] 2Component B

[0081] S3-4. Weigh the raw materials: 60-70 parts of 4,4-diphenylmethane diisocyanate, 25-30 parts of polypropylene glycol, 0.1 parts of antioxidant;

[0082] S3-5. In a reaction kettle under nitrogen protection, add polypropylene glycol, heat to 80℃, add 4,4-diphenylmethane diisocyanate dropwise at 300r / min, 1h is completed, after the dropwise addition is completed, heat to 85℃ and react for 3h, detect NCO to reach 12±0.5%, cool down to 40℃, add antioxidant, stir for 20min, discharge to obtain component B.

[0083] 3Elastic wear-resistant layer material

[0084] S3-6. Mix component A and component B at a mass ratio of 1:(1.1-1.2) to obtain the elastic wear-resistant layer material.

[0085] Preparation of high wear-resistant silicon PU composite layer

[0086] S4-1. Grind and remove dust on the concrete base surface, brush the sealing primer, the amount is 0.08-0.12kg / m 2 , dry at 25-28℃ for 3h to obtain the sealing primer;

[0087] S4-2. Mix component A and component B at a mass ratio of 1:(1.1-1.2), after mixing, scrape and coat on the dried sealing primer, the thickness is 6-8mm, cure at 25-28℃ for 6-8h to obtain the elastic wear-resistant layer;

[0088] S4-3. Apply the functional topcoat material on the elastic wear-resistant layer, with a coating thickness of 0.3-0.5 mm, and cure at 25-28°C for 24 h to obtain a functional topcoat, i.e., a high-wear-resistant silicon PU composite layer.

[0089] Example 2

[0090] Preparation of the functional topcoat material

[0091] S1-1. Weigh the raw materials: 48 parts of polypropylene glycol, 53 parts of 4, 4-diphenyl methane diisocyanate, 16 parts of 2, 2-dimethylol propionic acid, 45 parts of nano zirconium oxide dispersion, 1.0 parts of leveling agent, 0.2 parts of defoaming agent, and 0.6 parts of antioxidant;

[0092] S1-2. Put the polypropylene glycol and 2, 2-dimethylol propionic acid into the reaction kettle, stir uniformly at 110°C and 400 r / min, cool to 80°C, add 4, 4-diphenyl methane diisocyanate, and react for 3.5 h under nitrogen atmosphere. After the reaction is completed, cool to 37°C, and add the double-end hydroxypropyl silicone leveling agent, modified polysiloxane copolymer, and antioxidant in sequence under the condition of 1300 r / min stirring, and continue to stir for 25 min;

[0093] S1-3. Slowly add the nano zirconium oxide dispersion, increase the speed to 1700 r / min, and high-speed disperse for 25 min. Cool to 27°C, filter the material through a 200-mesh filter screen, and obtain the functional topcoat material.

[0094] Preparation of the sealing primer material

[0095] S2-1. Weigh the raw materials: 100 parts of epoxy silane oligomer, 2 parts of wetting agent, 0.2 parts of defoaming agent, 0.6 parts of antioxidant, and 50 parts of deionized water;

[0096] S2-2. At 25°C, put the epoxy silane oligomer into the stirring kettle, pre-disperse for 5 min at 550 r / min, and add the wetting agent, defoaming agent, and antioxidant in sequence, and continue to stir for 5 min;

[0097] S2-3. Slowly add the deionized water at 350 r / min, and complete the addition within 15 min to avoid local gelation. Warm to 35°C, and keep stirring for 30 min to make the system fully hydrolyze and homogenize. Filter the material through a 200-mesh filter screen to obtain the sealing primer material.

[0098] Preparation of modified Si3N4 / graphene composite powder

[0099] S3-1. Add 90 parts of Si3N4 and 10 parts of graphene oxide into 400 parts of anhydrous ethanol, and then add 0.5 parts of Tween-80. Ultrasonic at 600 W for 30 min to form a uniform suspension;

[0100] S3-2. Under stirring at 30℃ and 500 r / min, 3 parts of KH-560 (3% of the total mass of the powder) were added dropwise, and the pH was adjusted to 3.5-4.0 with glacial acetic acid, and ultrasonic treatment was continued for 15 min to make the coupling agent fully hydrolyzed and condensed with the surface hydroxyl groups of Si3N4 and graphene;

[0101] S3-3. The suspension was transferred into a reaction kettle, and kept at 120℃ for 4 h. After cooling, centrifugation was performed at 8000 r / min for 10 min, the supernatant was discarded, and the precipitate was collected and washed with anhydrous ethanol for 3 times to remove free silane. Vacuum drying was performed at 60℃ for 12 h, and the product was sieved through a 400-mesh sieve to obtain the modified Si3N4 / graphene composite powder.

[0102] Preparation of an elastic wear-resistant layer material

[0103] 1 Component A

[0104] S3-1. The raw materials were weighed: 35 parts of polypropylene glycol, 15 parts of hydroxyl-terminated polybutadiene, 13 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of heavy calcium carbonate, 4 parts of modified Si3N4 / graphene composite powder, 1 part of wetting agent, 0.6 parts of defoaming agent, 0.3 parts of leveling agent, 0.03 parts of dibutyltin dilaurate, 0.3 parts of antioxidant, and 0.5 parts of UV absorber.

[0105] S3-2. The polypropylene glycol and hydroxyl-terminated polybutadiene were placed in a reaction stirring kettle, vacuum dehydration was performed at 120℃ and -0.095 MPa for 2 h, and after dehydration, the temperature was lowered to 70℃. The wetting agent, part of the defoaming agent, heavy calcium carbonate, and modified Si3N4 / graphene composite powder were added in sequence, the stirring speed was increased to 1000 r / min, and continuous stirring was performed for 55 min to fully wet and disperse.

[0106] S3-3. The well-dispersed slurry was added with hydroxyl-terminated polydimethylsiloxane, and continuous stirring was performed at 500 r / min, -0.08 MPa, and 80℃ for 3 h. After the reaction was completed, the temperature was lowered to 55℃, and the remaining defoaming agent, leveling agent, dibutyltin dilaurate, UV absorber, and antioxidant were added. Stirring was performed at a speed of 200-400 r / min for 40 min, and the dispersion was uniform. The material was discharged to obtain component A.

[0107] 2 Component B

[0108] S3-4. The raw materials were weighed: 65 parts of 4,4-diphenylmethane diisocyanate, 27 parts of polypropylene glycol, and 0.1 parts of antioxidant.

[0109] S3-5. In a reaction kettle under nitrogen protection, polypropylene glycol was added, and the temperature was raised to 80℃. 4,4-diphenyl methane diisocyanate was added dropwise at 300r / min. After 1h, the temperature was raised to 85℃ and reacted for 3h. When the NCO content reached 12±0.5%, the temperature was lowered to 40℃. Antioxidant was added and stirred for 20min. The product was discharged to obtain component B.

[0110] 3 elastic wear-resistant layer material

[0111] S3-6. Component A and component B were mixed in a mass ratio of 1:1.1 to obtain the elastic wear-resistant layer material.

[0112] Preparation of high wear-resistant silicon PU composite layer

[0113] S4-1. The concrete base surface was polished and dusted, and a sealing primer was applied at a dosage of 0.08-0.12kg / m 2 , and dried at 25-28℃ for 3h to obtain a sealing primer;

[0114] S4-2. Component A and component B were mixed in a mass ratio of 1:1.1, and then scraped onto the dried sealing primer with a thickness of 6-8mm. After curing at 25-28℃ for 6-8h, an elastic wear-resistant layer was obtained.

[0115] S4-3. A functional finish layer material was coated on the elastic wear-resistant layer with a coating thickness of 0.3-0.5mm, and cured at 25-28℃ for 24h to obtain a functional finish layer, i.e. a high wear-resistant silicon PU composite layer.

[0116] Example 3

[0117] Preparation of functional finish layer material

[0118] S1-1. The raw materials were weighed: 50 parts of polypropylene glycol, 55 parts of 4,4-diphenyl methane diisocyanate, 20 parts of 2,2-dimethylol propionic acid, 50 parts of nano zirconium oxide dispersion, 1.5 parts of leveling agent, 0.3 parts of defoaming agent, and 0.7 parts of antioxidant.

[0119] S1-2. Polypropylene glycol and 2,2-dimethylol propionic acid were added to a reaction kettle and stirred uniformly at 110℃ and 500r / min. The temperature was lowered to 80℃, and 4,4-diphenyl methane diisocyanate was added. The reaction was carried out under nitrogen atmosphere for 4h. After the reaction was completed, the temperature was lowered to 40℃, and double-end hydroxypropyl silicone leveling agent, modified polysiloxane copolymer, and antioxidant were added in sequence under stirring at 1500r / min for 25min.

[0120] S1-3. Slowly add the nano zirconium oxide dispersion, increase the speed to 2000 r / min, and disperse at high speed for 30 min. Cool to 30°C, filter the material through a 200 mesh filter screen to obtain the functional cover layer material.

[0121] Preparation of a sealing primer material

[0122] S2-1. Weigh the raw materials: 100 parts of epoxy silane oligomer, 3 parts of wetting agent, 0.3 parts of defoaming agent, 0.7 parts of antioxidant, 50 parts of deionized water.

[0123] S2-2. At 30°C, put the epoxy silane oligomer into the stirred tank, pre-disperse at 600 r / min for 5 min, and then add the wetting agent, defoaming agent and antioxidant in sequence, and continue to stir for 5 min.

[0124] S2-3. Slowly add deionized water at 400 r / min, complete within 15 min to avoid local gelation. Warm up to 40°C and keep stirring for 30 min to fully hydrolyze and homogenize the system. Filter the material through a 200 mesh filter screen to obtain the sealing primer material.

[0125] Preparation of modified Si3N4 / graphene composite powder

[0126] S3-1. Add 90 parts of Si3N4 and 10 parts of graphene oxide to 400 parts of anhydrous ethanol, and then add 0.5 parts of Tween-80. Ultrasonic at 600 W for 30 min to form a uniform suspension.

[0127] S3-2. Under stirring at 30°C and 500 r / min, add 3 parts of KH-560 (3% of the total mass of the powder) dropwise, adjust the pH to 3.5-4.0 with glacial acetic acid, and continue to ultrasonic for 15 min to fully hydrolyze the coupling agent and condense it with the surface hydroxyl groups of Si3N4 and graphene.

[0128] S3-3. Transfer the suspension into a reaction kettle, keep at 120°C for 4 h, centrifuge at 8000 r / min for 10 min after cooling, discard the supernatant and collect the precipitate, wash with anhydrous ethanol for 3 times to remove free silane, vacuum dry at 60°C for 12 h, and pass through a 400 mesh screen to obtain the modified Si3N4 / graphene composite powder.

[0129] Preparation of an elastic wear-resistant layer material

[0130] 1 Component A

[0131] S3-1. Take the mass fraction of raw materials: 40 parts of polypropylene glycol, 20 parts of hydroxyl-terminated polybutadiene, 15 parts of hydroxyl-terminated polydimethylsiloxane, 40 parts of heavy calcium carbonate, 5 parts of modified Si3N4 / graphene composite powder, 1.5 parts of wetting agent, 0.8 parts of defoaming agent, 0.5 parts of leveling agent, 0.05 parts of dibutyltin dilaurate, 0.5 parts of antioxidant, 0.7 parts of UV absorber;

[0132] S3-2. Put the polypropylene glycol and hydroxyl-terminated polybutadiene into the reaction stirring kettle, vacuum dehydrate at 120℃, -0.095MPa for 2h, after dehydration, cool to 70℃, add wetting agent, part of defoaming agent, heavy calcium carbonate and modified Si3N4 / graphene composite powder in turn, increase the speed to 1000r / min, continue to stir for 60min, fully wet and disperse;

[0133] S3-3. Add hydroxyl-terminated polydimethylsiloxane to the dispersed slurry, continue to stir at 500r / min, -0.08MPa, 80℃ for 4h, after the reaction is completed, cool to 60℃, add the remaining defoaming agent, leveling agent, dibutyltin dilaurate, UV absorber, antioxidant, stir at 400r / min for 60min, disperse uniformly and discharge, to obtain component A.

[0134] 2Component B

[0135] S3-4. Take the mass fraction of raw materials: 70 parts of 4,4-diphenylmethane diisocyanate, 30 parts of polypropylene glycol, 0.1 parts of antioxidant;

[0136] S3-5. In a nitrogen-protected reaction kettle, add polypropylene glycol, heat to 80℃, add 4,4-diphenylmethane diisocyanate dropwise at 300r / min, 1h is completed, after the dropwise addition is completed, heat to 85℃ and react for 3h, detect NCO to reach 12±0.5%, cool to 40℃, add antioxidant, stir for 20min, discharge to obtain component B.

[0137] 3Elastic wear-resistant layer material

[0138] S3-6. Mix component A and component B according to the mass ratio of 1:1.2 to obtain the elastic wear-resistant layer material.

[0139] Preparation of high wear-resistant silicon PU composite layer

[0140] S4-1. Polish and remove dust on the concrete base surface, brush the sealing primer material, the amount is 0.08-0.12kg / m 2 , dry at 25-28℃ for 3h to obtain the sealing primer;

[0141] S4-2. Mix component A and component B at a mass ratio of 1:1.2, after mixing, scrape and coat on the dried closed base coat layer, the thickness is 6-8mm, and cure at 25-28℃ for 6-8h, to obtain the elastic wear-resistant layer;

[0142] S4-3. Apply the functional cover layer material on the elastic wear-resistant layer, the coating thickness is 0.3-0.5mm, and cure at 25-28℃ for 24h, to obtain the functional cover layer, that is, the high wear-resistant silicon PU composite layer.

[0143] Comparative Example 1

[0144] Preparation of Comparative Example 1

[0145] Refer to the preparation method of Example 2, the difference is that the nano zirconium oxide dispersion liquid is replaced by 18 parts of nano zirconium oxide solid particles with a particle size of 30nm, and the rest is consistent with Example 2, to obtain Comparative Example 1;

[0146] Preparation of Comparative Example 2

[0147] Refer to the preparation method of Example 2, the difference is that the modified Si3N4 / graphene composite powder is absent, and the amount is made up with heavy calcium carbonate, and the rest is consistent with Example 2, to obtain Comparative Example 2;

[0148] Preparation of Comparative Example 3

[0149] Refer to the preparation method of Example 2, the difference is that the modified Si3N4 / graphene composite powder is replaced by modified Si3N4 powder, and the rest is consistent with Example 2, to obtain Comparative Example 3;

[0150] The preparation method of the modified Si3N4 powder is as follows: 100 parts of Si3N4 is added into 400 parts of anhydrous ethanol, then 0.5 parts of Tween-80 is added, and ultrasonic treatment is performed at 600W for 30min to form a uniform suspension. Under stirring at 500r / min and 30℃, 3 parts of KH-560 (accounting for 3% of the total mass of the powder) is added dropwise, and the pH is adjusted to 3.5-4.0 with glacial acetic acid. Continue to ultrasonic treat for 15min, transfer the suspension into a reaction kettle, and heat at 120℃ for 4h. After cooling, centrifuge at 8000r / min for 10min, discard the supernatant and collect the precipitate. Wash the precipitate with anhydrous ethanol by centrifugation for 3 times, and vacuum dry at 60℃ for 12h. Then, sieve through a 400 mesh sieve to obtain the modified Si3N4 powder.

[0151] Preparation of Comparative Example 4

[0152] Refer to the preparation method of Example 2, the difference is that the hydroxyl-terminated polybutadiene is absent in the preparation process of the elastic wear-resistant layer, and the amount is made up with polypropylene glycol, and the rest is consistent with Example 2, to obtain Comparative Example 4.

[0153] Performance test

[0154] The silicon PU composite layers obtained from Examples 1-3 and Comparative Examples 1-4 were subjected to performance testing according to the test methods of GB 36246-2018 "Synthetic material surface layer of primary and secondary school playgrounds".

[0155] Table 1 Performance test results of silicon PU composite layer

[0156]

[0157] Result analysis:

[0158] According to the test results, the tensile strength of Examples 1-3 using nano zirconium oxide dispersion liquid before aging is 3.8-4.2 MPa, the elongation at break is 420-450%, and the wear resistance wear loss is 0.028-0.032 cm 3 ·1.61km -1 , which is significantly better than Comparative Examples 1-4;

[0159] Comparative Example 1 uses nano zirconium oxide solid particles instead of nano zirconium oxide dispersion liquid, which shows that the dispersion liquid form is more conducive to uniform distribution of nanoparticles, enhances the interface bonding and anti-aging ability;

[0160] Comparative Example 2 lacks modified Si3N4 / graphene composite powder, and the wear loss increases by 121% to 0.062 cm 3 ·1.61km -1 , and the rebound rate decreases to 60%, confirming that the modified composite powder is the key to improving wear resistance and elasticity.

[0161] Comparative Example 3 replaces the modified Si3N4 / graphene composite powder with modified Si3N4 powder, and the wear loss decreases compared to Comparative Example 2, but is still inferior to Example 2, indicating that coupling graphene with silicon nitride on the surface of silicon nitride reduces friction loss through the sliding of the graphene layer and the hard particles of Si3N4, and the introduction of modified composite powder into the polymer provides certain rigid support, improving the elasticity of the polymer material.

[0162] Comparative Example 4 lacks hydroxyl-terminated polybutadiene, and the rebound rate is only 52%, which is much lower than Example 2, and the wear loss increases by 96%, indicating that this component enhances the deformation recovery ability of the material through molecular chain flexibility, reducing permanent deformation.

[0163] In summary, the present application optimizes dispersibility through nano zirconium oxide dispersion liquid, enhances wear resistance through modified Si3N4 / graphene composite powder, and improves elasticity through hydroxyl-terminated polybutadiene, in combination with multi-layer composite design, significantly improving the comprehensive performance of the silicon PU surface layer. Example 2 is the optimal solution, fully meeting the high wear resistance, high elasticity and long-term durability requirements of the surface layer of the playground.

[0164] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that the technical solutions described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalent ones. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high wear resistant silicon PU composite layer, characterized in that, The composite layer comprises, from bottom to top, a closed bottom coating layer, an elastic wear-resistant layer and a functional top coating layer, the closed bottom coating layer is coated by a closed bottom coating layer material, the elastic wear-resistant layer is coated by an elastic wear-resistant layer material, and the functional top coating layer is coated by a functional top coating layer material; The functional top coating layer material contains the following components in mass fraction: 45-50 parts of polypropylene glycol, 50-55 parts of 4, 4-diphenyl methane diisocyanate, 15-20 parts of 2, 2-dimethylol propionic acid, 40-50 parts of nano zirconium oxide dispersion, 0.5-1.5 parts of leveling agent, 0.1-0.3 parts of defoaming agent, 0.5-0.7 parts of antioxidant; The elastic wear-resistant layer material is mixed by component A and component B in mass ratio 1:(1.1-1.2); The component A contains the following components in mass fraction: 30-40 parts of polypropylene glycol, 10-20 parts of hydroxyl-terminated polybutadiene, 10-15 parts of hydroxyl-terminated polydimethylsiloxane, 25-40 parts of heavy calcium carbonate, 2-5 parts of modified Si3N4 / graphene composite powder, 0.5-1.5 parts of wetting agent, 0.3-0.8 parts of defoaming agent, 0.1-0.5 parts of leveling agent, 0.01-0.05 parts of dibutyltin dilaurate, 0.2-0.5 parts of antioxidant, 0.4-0.7 parts of UV absorber; The component B contains the following components in mass fraction: 60-70 parts of 4, 4-diphenyl methane diisocyanate, 25-30 parts of polypropylene glycol, 0.1 parts of antioxidant; The closed bottom coating layer material contains the following components in mass fraction: 90-110 parts of epoxy silane oligomer, 2-3 parts of wetting agent, 0.1-0.3 parts of defoaming agent, 0.5-0.7 parts of antioxidant, 45-55 parts of deionized water.

2. The high wear resistant silicone PU composite layer according to claim 1, characterized in that, The leveling agent is double-end hydroxypropyl silicone oil; The defoaming agent is modified polysiloxane copolymer; The antioxidant is antioxidant 1010; The wetting agent is alkyl phenol polyoxyethylene ether; The UV absorber is Tinuvin 326.

3. The high wear resistant silicon PU composite layer according to claim 1 or 2, characterized in that, The preparation method of the modified Si3N4 / graphene composite powder comprises the following steps: S1.

1. Si3N4 and graphene oxide in a mass ratio of 9:1 are added to anhydrous ethanol, the mass ratio of the material to the liquid is 1:40, 0.1% of Tween-80 is added, ultrasonic is performed at 600W for 30min to form a uniform suspension; S1.

2. Under the condition of 30℃ and 500r / min stirring, 2-3% of KH-560 of the mass of Si3N4 and graphene oxide composite powder is added dropwise, the pH of the system is adjusted to 3.5-4.0, ultrasonic is continued for 15min, then the temperature is increased to 120℃ and reacted for 4h, after cooling, centrifugation is performed at 8000r / min for 10min, the supernatant is discarded and the solid precipitate is collected, dried and sieved to obtain the modified Si3N4 / graphene composite powder.

4. The high wear resistant silicon PU composite layer according to claim 1 or 2, characterized in that, The preparation method of the component A comprises the following steps: S2.

1. Put polypropylene glycol and hydroxyl-terminated polybutadiene into a reaction stirred tank, dehydrate at 120℃, -0.095MPa for 2h, after dehydration, cool down to 70℃, add wetting agent, part of defoaming agent, heavy calcium carbonate and modified Si3N4 / graphene composite powder, increase the rotation speed to 1000r / min, continue stirring for 50-60min, fully wet and disperse; S2.

2. Add hydroxyl-terminated polydimethylsiloxane to the dispersed slurry, continuously stir at 500r / min, -0.08MPa, 80℃ for 2-4h, after reaction, cool down to 50-60℃, add the rest of defoaming agent, leveling agent, dibutyltin dilaurate, UV absorber, antioxidant, stir at 200-400r / min for 30-60min, disperse uniformly, discharge, to obtain component A.

5. The high wear resistant silicon PU composite layer according to claim 1 or 2, characterized in that, The preparation method of the component B comprises the following steps: In a reaction kettle under nitrogen protection, add polypropylene glycol, heat to 80℃, add 4,4-diphenyl methane diisocyanate at 300r / min, 1h for addition, after dropwise addition, heat to 85℃, keep for 3h, cool down to 40℃, add antioxidant, stir for 20min, discharge to obtain component B.

6. The high wear resistant silicon PU composite layer according to claim 1 or 2, characterized in that, The preparation method of the closed primer material comprises the following steps: S3.

1. Put epoxy silane oligomer into a stirred tank at 20-30℃, pre-disperse at 500-600r / min for 5min, add wetting agent, defoaming agent, antioxidant in sequence, continue stirring for 5min; S3.

2. Add deionized water at 300-400r / min, heat to 35-40℃, keep stirring for 30min, filter through a 200 mesh filter screen, discharge to obtain the closed primer material.

7. The high wear resistant silicon PU composite layer according to claim 1 or 2, characterized in that, The preparation method of the functional topcoat material comprises the following steps: S4.

1. Put polypropylene glycol and 2,2-dimethylol propionic acid into a reaction kettle, stir uniformly at 110℃, 300-500r / min, cool down to 80℃, add 4,4-diphenyl methane diisocyanate, react for 3-4h under nitrogen atmosphere, after reaction, cool down to 35-40℃, add double hydroxypropyl silicone leveling agent, modified polysiloxane copolymer defoaming agent, antioxidant in sequence under the condition of 1000-1500r / min stirring, continue stirring for 25min; S4.

2. Slowly add nano zirconium oxide dispersion liquid, increase the rotation speed to 1500-2000r / min, high speed dispersion for 20-30min, cool down to 25-30℃, filter through a 200 mesh filter screen, discharge to obtain the functional topcoat material.

8. The high wear resistant silicone PU composite layer of claim 1, wherein, The average particle size of zirconium oxide in the nano zirconium oxide dispersion liquid is 30nm, and the solid content is 20-40%.

9. The application of the high wear-resistant silicon PU composite layer in claim 1-8 in preparing a court surface layer.

10. The method for preparing the high wear-resistant silicone PU composite layer according to any one of claims 1-8, characterized in that, The preparation method comprises the following steps: S5.

1. Dusting and polishing the concrete base surface, and brushing the sealing primer material with an amount of 0.08-0.12 kg / m 2 drying at 25-28 °C for 3 h to obtain the sealing primer. S5.

2. Mix component A and component B at a mass ratio of 1:(1.1-1.2), and after mixing, scrape and coat on the dried closed base coating layer at a thickness of 6-8 mm, and cure at 25-28°C for 6-8 h to obtain an elastic wear-resistant layer; S5.

3. Coat a functional finish layer material on the elastic wear-resistant layer at a coating thickness of 0.3-0.5 mm, and cure at 25-28°C for 24 h to obtain a functional finish layer, i.e. a high-wear-resistant silicon PU composite layer.

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