Modified rubber powder as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of rubber preparation, and particularly relates to modified rubber powder as well as a preparation method and application thereof. Raw materials of the rubber powder comprise the following components: waste rubber powder, an auxiliary agent, a reinforcing agent and a surfactant. The preparation method of the modified rubber powder comprises the following steps: adding an auxiliary agent into waste rubber powder, soaking, carrying out ultrasonic treatment, standing for layering, removing supernatant liquid, adding water for cleaning, and removing water to obtain pretreated waste rubber powder; and mixing the pretreated waste rubber powder, a reinforcing agent and a surfactant uniformly, drying, grinding, and sieving with a 80-100-mesh sieve to obtain the product. The prepared modified rubber powder is high in tensile strength, high in elongation at break and high in wear resistance, and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber preparation, and in particular relates to modified rubber powder and a preparation method and application thereof. Background Art

[0002] The resource recovery and harmless treatment of waste tire rubber can not only effectively alleviate the current pressure of environmental pollution caused by waste rubber, but also has important significance for solving the shortage of rubber resources. Waste rubber powder is an important type of waste rubber recycling product. The development of deep processing technology for rubber powder is an important technical approach to achieve high-value utilization of waste rubber. Rubber powder is treated by physical, chemical or biological methods so that the modified rubber powder can be well combined with the matrix material. In the process of two-phase melt blending, the rubber powder can be better dispersed in the matrix material, so that the performance of the composite material is significantly improved. Through modification, the use value of rubber powder can be improved and its application field can be broadened, which has important theoretical and practical significance for the large-scale industrial application of rubber powder.

[0003] Chinese invention patent application CN117209947A discloses a composite modified EPDM rubber material for water pipe sealing and a preparation method thereof, wherein the composite modified EPDM rubber material comprises modified EPDM rubber powder and polymer filler; wherein the polymer filler comprises modified polyvinyl chloride powder and ethyl acrylate rubber powder. In the present invention, EPDM rubber is grafted and modified with di[2-(acryloyloxy)ethyl]phosphate to obtain modified EPDM rubber powder, polyvinyl chloride is grafted with methacrylate to obtain modified polyvinyl chloride, and then the ethyl acrylate rubber is surface activated with a surfactant, and finally blended and modified to obtain a composite modified EPDM rubber material. The technical solution provided by the invention can improve the compatibility between the three, overcome the shortcomings of traditional rubber materials for water pipe sealing, and enhance water resistance, corrosion resistance and chloramine resistance.

[0004] Chinese invention patent application CN116496558A discloses a modified rubber powder and a preparation method thereof. The modified nano Al2O3 / carbon fiber is prepared by acid washing carbon fiber, in-situ coating Al2O3, treating with a silane coupling agent, and modifying with cystamine; then 100 parts of rubber powder and 10-15 parts of modified nano Al2O3 / carbon fiber are weighed by weight and added into an internal mixer, and then 5-10 parts of methyl methacrylate, 5-10 parts of calcium carbonate, and 0.2-0.6 parts of sodium persulfate are added, and the mixture is swollen and mixed uniformly and reacted. After the reaction is completed, the product is ground and sieved to obtain a modified rubber powder; the modified rubber powder has good tensile strength, elongation at break, and wear resistance.

[0005] The prior art has explored the preparation of rubber powder to some extent and has made some progress. However, there is still a lot of room for the development of fine rubber powder, and its performance needs to be further improved and enhanced. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a modified rubber powder with high tensile strength, high elongation at break and excellent wear resistance.

[0007] In order to achieve the purpose of the present invention, the technical solution adopted is as follows:

[0008] A modified rubber powder, the raw materials of which include the following components: waste rubber powder, auxiliary agent, reinforcing agent and surfactant.

[0009] Preferably, the raw materials of the rubber powder include the following components by weight: 90-110 parts of waste rubber powder, 1-5 parts of additives, 10-20 parts of reinforcing agents, 0.5-1 parts of silane coupling agents and 5-10 parts of surfactants.

[0010] Preferably, the auxiliary agent comprises, by mass percentage, 5%-10% polyoxyethylene nonylphenol ether, 5%-10% sodium oleate, 1-5% oxalic acid, and the balance is water.

[0011] Preferably, the reinforcing agent is one or more of modified kaolin, modified bentonite, and nano-silicon dioxide; and the surfactant is selected from sodium dodecyl sulfate.

[0012] Preferably, the reinforcing agent is nano-modified kaolin;

[0013] Preferably, the preparation method of the nano-modified kaolin comprises dispersing kaolin in an ethanol aqueous solution with a volume concentration of 30-50%, adding a silane coupling agent, mixing, stirring at 50-70° C. for 30-50 minutes, filtering, drying, grinding, and sieving to obtain the modified kaolin.

[0014] Preferably, the silane coupling agent is γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2-0.5, and the mass ratio of kaolin to the silane coupling agent is 1:0.05-0.1.

[0015] The second object of the present invention is to provide a method for preparing the modified rubber powder, comprising the following steps:

[0016] (1) soaking the waste rubber powder with an additive, ultrasonicating, standing and stratifying, removing the upper clear liquid, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0017] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed and kneaded evenly, dried and ground through a 80-100 mesh sieve to obtain the product.

[0018] Preferably, the soaking time in step (1) is 5-10 min, and the ultrasonication time is 10-30 min.

[0019] Preferably, the mixing temperature in step (2) is 130-145° C. and the mixing time is 20-45 min.

[0020] The third object of the present invention is to provide the use of the modified rubber powder or the modified rubber powder obtained by the above preparation method in the preparation of tires, concrete or cables.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention uses a compound silane coupling agent to modify kaolin, and the self-made modified kaolin is used for the preparation of rubber powder, which ultimately significantly enhances the reinforcing effect of the rubber powder. By introducing specific compound functional groups, the surface morphology is made looser, and the wear resistance and tensile strength of the obtained rubber are significantly improved.

[0023] (2) The present invention also focuses on the study of additives and finds that before modifying the rubber powder, the waste rubber powder is pre-treated by adding the solution system of the present invention, which can improve the purity and performance of the waste rubber powder and effectively improve the tensile strength and anti-tensile strength of the later rubber.

[0024] (3) The present invention improves the performance of rubber powder through formula and preparation process improvement, and also realizes the recycling of waste rubber powder. It realizes the reduction, reuse and resource utilization of rubber powder, and promotes the characteristic construction of "resource-saving and environmentally friendly" fine rubber powder preparation. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with specific embodiments. The following raw materials are all commercially available conventional raw materials. Among them, the supplier of the above waste rubber powder is Gaoxian Huagui Mining Co., Ltd., and the supplier of kaolin is Lingshou County Jushi Mineral Products Processing Plant.

[0026] Example 1

[0027] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0028] The additives are 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water in terms of mass percentage.

[0029] The surfactant is selected from sodium lauryl sulfate.

[0030] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.4) 0.05 times the mass of kaolin, mixing, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain.

[0031] The preparation method of modified rubber powder is as follows:

[0032] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0033] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0034] Example 2

[0035] A modified rubber powder comprises the following raw materials by weight: 90 parts of waste rubber powder, 1 part of auxiliary agent, 10 parts of reinforcing agent and 5 parts of surfactant.

[0036] The additives are calculated by mass percentage as follows: 5% polyoxyethylene nonylphenol ether, 10% sodium oleate, 1% oxalic acid, and the balance is water.

[0037] The surfactant is selected from sodium lauryl sulfate.

[0038] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in a 30% ethanol aqueous solution, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2) 0.05 times the mass of kaolin, mixing, stirring at 50°C for 30 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain the reinforcing agent.

[0039] The preparation method of modified rubber powder comprises the following steps:

[0040] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0041] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 145° C. for 20 minutes. After mixing evenly, the mixture is dried and ground through a 100-mesh sieve.

[0042] Example 3

[0043] A modified rubber powder comprises the following components in parts by weight: 110 parts of waste rubber powder, 5 parts of auxiliary agent, 20 parts of reinforcing agent and 10 parts of surfactant.

[0044] The additives are calculated by mass percentage as follows: 10% polyoxyethylene nonylphenol ether, 5% sodium oleate, 5% oxalic acid, and the balance is water.

[0045] The surfactant is selected from sodium lauryl sulfate.

[0046] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in an ethanol aqueous solution with a volume concentration of 50%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane with a mass ratio of 1:0.5) 0.1 times the mass of kaolin, stirring at 70°C for 50 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain the reinforcing agent.

[0047] The preparation method of modified rubber powder comprises the following steps:

[0048] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0049] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0050] Comparative Example 1

[0051] This comparative example is different from Example 1 in that the auxiliary agent is different.

[0052] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0053] The additives are 16% polyoxyethylene nonylphenol ether, 2% oxalic acid and the balance is water in terms of mass percentage.

[0054] The surfactant is selected from sodium lauryl sulfate.

[0055] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.4) 0.05 times the mass of kaolin, mixing, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain.

[0056] The preparation method of modified rubber powder is as follows:

[0057] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0058] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0059] Comparative Example 2

[0060] This comparative example is different from Example 1 in that the auxiliary agent is different.

[0061] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0062] The additives are calculated by mass percentage as follows: 16% sodium oleate, 2% oxalic acid, and the balance is water.

[0063] The surfactant is selected from sodium lauryl sulfate.

[0064] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.4) 0.05 times the mass of kaolin, mixing, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain.

[0065] The preparation method of modified rubber powder is as follows:

[0066] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0067] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0068] Comparative Example 3

[0069] The difference between this comparative example and Example 1 is that the reinforcing agent is different, which is commercially available white carbon black.

[0070] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0071] The additives are 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water in terms of mass percentage.

[0072] The surfactant is selected from sodium lauryl sulfate.

[0073] The reinforcing agent is white carbon black.

[0074] The preparation method of modified rubber powder is as follows:

[0075] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0076] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

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

[0078] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0079] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed and kneaded evenly, dried and ground through an 80-mesh sieve to obtain the product.

[0080] Comparative Example 4

[0081] The difference between this comparative example and Example 1 is that the reinforcing agent is prepared in a different method.

[0082] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0083] The additives are 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water in terms of mass percentage.

[0084] The surfactant is selected from sodium lauryl sulfate.

[0085] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in 45% ethanol aqueous solution, adding 0.05 times of silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0086] The preparation method of modified rubber powder is as follows:

[0087] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0088] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0089] Comparative Example 5

[0090] The difference between this comparative example and Example 1 is that the reinforcing agent is prepared in a different method.

[0091] A modified rubber powder comprises the following raw materials by weight: 100 parts of waste rubber powder, 3 parts of auxiliary agent, 15 parts of reinforcing agent and 7 parts of surfactant.

[0092] The additives are 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water in terms of mass percentage.

[0093] The surfactant is selected from sodium lauryl sulfate.

[0094] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in 45% ethanol aqueous solution, adding 0.05 times of silane coupling agent γ-mercaptopropyltrimethoxysilane) to mix, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0095] The preparation method of modified rubber powder is as follows:

[0096] (1) adding an additive to the waste rubber powder and soaking it for 5 minutes, ultrasonicating it for 30 minutes, standing it for stratification, removing the upper clear liquid, washing it with water, and removing the water to obtain the pretreated waste rubber powder;

[0097] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed at 130° C. for 45 minutes. After mixing evenly, the mixture is dried and ground through an 80-mesh sieve.

[0098] The modified rubber powder prepared in each embodiment and comparative example was rolled into sheets and pressed into films according to the test formula of tensile strength and elongation at break in GB / T19208-2020 "Vulcanized Rubber Powder", and the tensile strength and elongation at break were tested according to the national standard GB / T 528-2009, and the Akron abrasion performance of the pressed film product was tested according to GB / T 1689-2014. The results are shown in Table 1.

[0099] Table 1 Mechanical properties test results

[0100]

[0101] After the above-mentioned sheeting and film pressing molding were carried out using the rubber powder of Example 1 of the present invention, the remaining test results of the product are as follows in Table 2:

[0102] Table 2

[0103] No. Inspection items Technical requirements / standard values Test results Conclusion of this item 1 Heating loss, % ≤1.0 0.3 qualified 2 Ash content, % ≤1.0 8 qualified 3 Acetone extract, % ≤8 5 qualified 4 Rubber hydrocarbon content, % >45 65 qualified 5 Carbon black content, % >26 29 qualified 6 Iron content, % <0.05 0.008 qualified 7 <![CDATA[Bulk density, (kg / m 3 )]]> 260-380 321 qualified 8 Screen residue, % ≤10 0.01 qualified

[0104] The above detailed description is a specific description of one feasible embodiment of the present invention. The embodiment is not intended to limit the patent scope of the present invention. Any equivalent implementation or modification that does not deviate from the present invention should be included in the scope of the technical solution of the present invention.

Claims

1. A modified rubber powder, characterized in that: The raw materials of the rubber powder include the following components: waste rubber powder, additives, reinforcing agents and surfactants.

2. The modified rubber powder according to claim 1, characterized in that The raw materials of the rubber powder include the following components by weight: 90-110 parts of waste rubber powder, 1-5 parts of auxiliary agent, 10-20 parts of reinforcing agent and 5-10 parts of surfactant.

3. The modified rubber powder according to claim 1, characterized in that: The auxiliary agent comprises 5%-10% polyoxyethylene nonylphenol ether, 5%-10% sodium oleate, 1-5% oxalic acid and the balance is water in terms of mass percentage.

4. The modified rubber powder according to claim 1, characterized in that: The reinforcing agent is one or more of modified kaolin, modified bentonite and nano silicon dioxide; the surfactant is selected from sodium dodecyl sulfate.

5. The modified rubber powder according to claim 4, characterized in that: The reinforcing agent is nano-modified kaolin. The preparation method of the nano-modified kaolin includes dispersing kaolin in an ethanol aqueous solution with a volume concentration of 30-50%, adding a silane coupling agent, mixing, stirring at 50-70° C. for 30-50 minutes, filtering, drying, grinding, and sieving to obtain the reinforcing agent.

6. The modified rubber powder according to claim 5, characterized in that: The silane coupling agent is γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2-0.5, and the mass ratio of kaolin and the silane coupling agent is 1:0.05-0.

1.

7. A method for preparing the modified rubber powder according to any one of claims 1 to 6, characterized in that: The steps include: (1) soaking the waste rubber powder with an additive, ultrasonicating, standing and stratifying, removing the upper clear liquid, washing with water, and removing the water to obtain the pretreated waste rubber powder; (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed and kneaded evenly, dried and ground through a 80-100 mesh sieve to obtain the product.

8. The preparation method according to claim 7, characterized in that: The soaking time in step (1) is 5-10 minutes, and the ultrasonication time is 10-30 minutes.

9. The preparation method according to claim 7, characterized in that: The mixing temperature in step (2) is 130-145° C., and the mixing time is 20-45 min.

10. Use of the modified rubber powder according to any one of claims 1 to 6 or the modified rubber powder obtained by the preparation method according to any one of claims 7 to 9 in the preparation of tires, concrete or cables.

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