Preparation method of rubber and plastic blended brake pad

Abstract

The invention relates to a preparation method of a rubber and plastic blended brake pad, and belongs to the technical field of brake pad preparation. The rubber and plastic blended brake pad is obtained by mixing and vulcanizing the rubber, the plastic, the reinforcing agent, the stearic acid, the zinc oxide, the anti-aging agent, the accelerant, the sulfur and the vulcanizing agent. According to the epoxy modified white carbon black disclosed by the invention, epoxy groups on the surface of the epoxy modified white carbon black and amino groups in a rare earth terbium phenanthroline complex are subjected to a so-called amino-epoxy ring-opening reaction; then, the other epoxy group on the modified white carbon black and the amino group of 2-amino lithium adipate are subjected to a secondary amino-epoxy ring-opening reaction; the stage ensures that the rare earth complex and the lithium 2-amino adipate are uniformly distributed and stably anchored on the surface of the white carbon black, so that the functionality, the stability and the wear resistance of the final material are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of brake pad preparation, and in particular to a preparation method of a rubber-plastic blended brake pad. Background Art

[0002] Automobile brake pads, also known as automotive brake linings, refer to the friction materials fixed on the brake drums or brake discs that rotate with the wheels. The friction linings and friction blocks therein bear external pressures and generate frictional forces to achieve the purpose of vehicle deceleration.

[0003] Chinese Patent CN105987110A: discloses a manufacturing process for automobile brake pads. Calculated by weight, its characteristics are as follows: a. Take 20-25 parts of phenolic resin, 10-13 parts of nitrile latex, 20-22 parts of natural graphite, 4 parts of kaolin, 10-11 parts of carbon fiber, 20-22 parts of wollastonite fiber, and 20-21 parts of calcium carbonate, put them into a stirring device, and stir for 5 minutes to mix them evenly; b. Make the mixed materials into particles with a diameter of 3 mm, and then put them into an oven for baking at a temperature of 120 °C for 3 hours; c. Put the twice-mixed materials in a stirring device and stir for 5 minutes to mix them evenly; d. Weigh the finally mixed materials by piece and perform hot pressing and molding; e. Put the pressed friction material product into an oven for baking at a temperature of 190 ± 2 °C.

[0004] Chinese Patent CN103161859A: discloses an automobile brake pad, which is prepared from the following materials by weight percentage according to the conventional brake pad pressing method: bamboo charcoal fiber 10-10%, graphite 5-15%, antimony sulfide 5-10%, barium sulfate 15-25%, epoxy resin 10-20%, abrasion-increasing agent 1-5%, coke powder 3-20%, potassium feldspar 7-11%, glass powder 5-15%, nitrile rubber 1-3%, calcium oxide 1-2%, rice husk 5-30%.

[0005] Chinese Patent CN113757279B: relates to the technical field of automobile brake pads, and in particular to an automobile brake pad for an aluminum alloy brake disc containing alkaline earth metal oxides and its preparation method. In the present invention, bismaleimide-modified phenolic resin, epichlorohydrin rubber, aluminum borate whiskers, polypropylene mesh fiber, antigorite, hydrotalcite, alkaline earth metal oxides, magnesite, bentonite, and cork powder are put into a mixer in proportion, and the mixture is obtained after mixing; then the steel back and the mixture are placed in a mold for molding by die pressing to obtain a blank; finally, the blank is heated and cured to process the automobile brake pad.

[0006] The brake pads prepared by the above patents and the prior art mainly include asbestos brake pads and metal brake pads. Asbestos brake pads have "thermal fade" caused by a large increase in wear rate when used at high temperatures; while metal brake pads have defects such as too fast deceleration and poor riding comfort due to their large mass. Summary of the Invention

[0007] (1) Technical Problem to be Solved

[0008] The present invention provides a preparation method of a rubber-plastic blended brake pad. By mixing rubber, plastic, reinforcing agent, stearic acid, zinc oxide, antioxidant, accelerator, sulfur, and vulcanizing agent, and then performing mixing and vulcanization, a rubber-plastic blended brake pad is obtained, which improves the wear resistance of the brake.

[0009] (2) Technical Solution

[0010] A preparation method of a rubber-plastic blended brake pad, and its operation steps are as follows:

[0011] S1: By weight, weigh 10 - 20 parts of rubber and 60 - 80 parts of plastic, add them to an open mill for mixing for 10 - 15 min, and the roll temperature is 110 - 150 °C;

[0012] S2: Continue to add 5 - 10 parts of reinforcing agent, 0.1 - 0.5 part of stearic acid, 0.5 - 1 part of zinc oxide, 0.1 - 0.3 part of antioxidant, 0.1 - 0.3 part of accelerator, 0.1 - 0.3 part of sulfur, 0.5 - 1 part of vulcanizing agent, and continue to mix for 10 - 20 min. The roll temperature is 50 - 60 °C. After mixing evenly, let it stand for 20 - 25 h;

[0013] S3: Put the mixed material on a flat vulcanizer for vulcanization to obtain a rubber-plastic blended brake pad.

[0014] Preferably, the rubber is ethylene propylene diene monomer (EPDM) rubber or nitrile rubber.

[0015] Preferably, the plastic is high-density polyethylene or polyvinyl chloride.

[0016] Preferably, the reinforcing agent is modified fumed silica, and its modification method is as follows:

[0017] By weight, add 4 - 8 parts of silane coupling agent KH560 to 1000 - 1500 parts of ethanol, then add 100 - 150 parts of fumed silica, continuously stir at 40 - 50 °C for 30 - 70 min, then add 0.03 - 0.3 part of rare earth terbium phenanthroline complex, 1.5 - 3.5 parts of tert-butyl potassium, 0.01 - 0.1 part of lithium 2-aminocaproate, continuously stir at 60 - 70 °C for 100 - 150 min, filter, and dry to obtain modified fumed silica.

[0018] Preferably, the preparation method of the rare earth terbium phenanthroline complex is as follows:

[0019] By weight, 20 - 40 parts of 5 - aminophenanthroline, 35 - 70 parts of terbium triacetate hydrate, 200 - 300 parts of distilled water, and 10 - 20 parts of ammonia water are stirred in a reaction kettle at 50 - 70 °C for 2 - 4 hours. Then, water is distilled off and dried to obtain the rare - earth terbium phenanthroline complex.

[0020] Preferably, the antioxidant is one of antioxidant AW, antioxidant RD, antioxidant A, antioxidant 4010, antioxidant 4010NA, antioxidant H, and antioxidant D.

[0021] Preferably, the accelerator is one of accelerator TMTD, accelerator TMTM, accelerator PZ, accelerator EZ, accelerator ZBX, accelerator ZIP, accelerator DM, and accelerator M.

[0022] Preferably, the vulcanizing agent is one of morpholine disulfide, N, N'-di - caprolactam disulfide, bis(diethylthiophosphoryl) trisulfide, morpholine tetrasulfide, and selenium diethyldithiocarbamate.

[0023] Preferably, the vulcanization temperature is 120 - 140 °C, the pressure is 3 - 4 MPa, and the time is 20 - 40 min.

[0024] (III) Reaction mechanism

[0025] Ring - opening reaction of epoxy group and amino group: The epoxy - modified silica involves the so - called amino - epoxy ring - opening reaction between the epoxy groups on its surface and the amino groups in the rare - earth terbium phenanthroline complex; subsequently, another epoxy group on the modified silica reacts with the amino group of lithium 2 - aminoadipate to undergo a second amino - epoxy ring - opening reaction; this stage ensures the uniform distribution and stable anchoring of the rare - earth complex and lithium 2 - aminoadipate on the silica surface, enhancing the functionality and stability of the final material.

[0026] (IV) Beneficial technical effects

[0027] 1. Improve wear resistance: Introducing the terbium - containing phenanthroline complex and lithium adipate through the modification reaction significantly improves the surface hardness of silica and its dispersibility in the polymer matrix. This improvement in physical properties is translated into an increase in the wear resistance of the brake pads, reducing the loss under high temperature and high pressure.

[0028] 2. Enhance interfacial adhesion: Through modification, the rare - earth complex and lithium adipate grafted on the silica surface can improve its adhesion strength with the brake - pad matrix (usually various rubbers or composite materials). This enhanced interfacial bonding can effectively prevent peeling or particle detachment during friction, thus extending the service life of the brake pads. Specific embodiments

[0029] The present invention will be further described below in conjunction with embodiments, but the present invention is not limited to these examples. Any improvements made without departing from the spirit of the present invention fall within the protection scope of the present invention.

[0030] Embodiment 1

[0031] A preparation method of a rubber-plastic blend brake pad, the operation steps of which are as follows:

[0032] S1: Weigh 10 g of rubber and 60 g of plastic, add them to an open mill for mixing for 10 min, and the roll temperature is 110 °C;

[0033] S2: Continuously add 5 g of reinforcing agent, 0.1 g of stearic acid, 0.5 g of zinc oxide, 0.1 g of antioxidant, 0.1 g of accelerator, 0.1 g of sulfur, 0.5 g of vulcanizing agent, and continue mixing for 10 min. The roll temperature is 50 °C. After mixing evenly, let it stand for 20 h;

[0034] S3: Put the mixed material on a flat vulcanizer for vulcanization to obtain a rubber-plastic blend brake pad.

[0035] The rubber is ethylene propylene diene monomer rubber.

[0036] The plastic is high-density polyethylene.

[0037] The reinforcing agent is modified fumed silica, and its modification method is as follows:

[0038] Add 4 g of silane coupling agent KH560 to 1000 g of ethanol, then add 100 g of fumed silica, continuously stir at 40 °C for 30 min, then add 0.03 g of rare earth terbium phenanthroline complex, 1.5 g of potassium tert-butoxide, 0.01 g of lithium 2-aminocaproate, continuously stir at 60 °C for 100 min, filter, and dry to obtain modified fumed silica.

[0039] The preparation method of the rare earth terbium phenanthroline complex is as follows:

[0040] Mix 20 g of 5-amino-1,10-phenanthroline with 35 g of terbium triacetate hydrate, 200 g of distilled water, and 10 g of ammonia water, stir in a reaction kettle at 50 °C for 2 hours, distill off the water, and dry to obtain the rare earth terbium phenanthroline complex.

[0041] The antioxidant is antioxidant AW.

[0042] The accelerator is accelerator TMTD.

[0043] The vulcanizing agent is morpholine disulfide.

[0044] The vulcanization temperature is 120 °C, the pressure is 3 MPa, and the time is 20 min.

[0045] Example 2

[0046] A preparation method of a rubber-plastic blended brake pad, the operation steps of which are as follows:

[0047] S1: Weigh 13 g of rubber and 63 g of plastic, add them to an open mill for mixing for 12 min, and the roll temperature is 120 °C;

[0048] S2: Continuously add 6 g of reinforcing agent, 0.2 g of stearic acid, 0.6 g of zinc oxide, 0.2 g of antioxidant, 0.2 g of accelerator, 0.2 g of sulfur, 0.6 g of vulcanizing agent, and continue mixing for 15 min. The roll temperature is 55 °C. After mixing evenly, let it stand for 22 h;

[0049] S3: Put the mixed material on a flat vulcanizer for vulcanization to obtain a rubber-plastic blended brake pad.

[0050] The rubber mentioned above is ethylene-propylene-diene monomer rubber.

[0051] The plastic mentioned above is high-density polyethylene.

[0052] The reinforcing agent mentioned above is modified fumed silica, and its modification method is as follows:

[0053] Add 5 g of silane coupling agent KH560 to 1100 g of ethanol, then add 110 g of fumed silica, continuously stir at 45 °C for 40 min, then add 0.1 g of rare earth terbium o-phenanthroline complex, 2 g of potassium tert-butoxide, 0.05 g of lithium 2-aminoadipate, continuously stir at 65 °C for 110 min, filter, and dry to obtain modified fumed silica.

[0054] The preparation method of the rare earth terbium o-phenanthroline complex mentioned above is as follows:

[0055] Mix 25 g of 5-amino-o-phenanthroline with 45 g of terbium triacetate hydrate, 240 g of distilled water, and 13 g of ammonia water in a reaction kettle at 55 °C and stir for 3 hours. Distill off the water and dry to obtain the rare earth terbium o-phenanthroline complex.

[0056] The antioxidant mentioned above is antioxidant RD.

[0057] The accelerator mentioned above is accelerator TMTM.

[0058] The vulcanizing agent mentioned above is N, N'-dihexanoyl disulfide.

[0059] The vulcanization temperature mentioned above is 125 °C, the pressure is 3.5 MPa, and the time is 25 min.

[0060] Example 3

[0061] A preparation method of a rubber-plastic blended brake pad, the operation steps of which are as follows:

[0062] S1: Weigh 18 g of rubber and 75 g of plastic, add them to an open mill for mixing for 14 min, and the roll temperature is 140 °C;

[0063] S2: Continuously add 8 g of reinforcing agent, 0.4 g of stearic acid, 0.8 g of zinc oxide, 0.2 g of antioxidant, 0.2 g of accelerator, 0.2 g of sulfur, 0.8 g of vulcanizing agent, and continue mixing for 15 min. The roll temperature is 55 °C. After mixing evenly, let it stand for 24 h;

[0064] S3: Put the mixed material on a flat vulcanizer for vulcanization to obtain a rubber-plastic blend brake pad.

[0065] The rubber mentioned above is nitrile rubber.

[0066] The plastic mentioned above is polyvinyl chloride.

[0067] The reinforcing agent mentioned above is modified fumed silica, and its modification method is:

[0068] Add 7 g of silane coupling agent KH560 to 1400 g of ethanol, then add 140 g of fumed silica, continuously stir at 45 °C for 60 min, then add 0.2 g of rare earth terbium phenanthroline complex, 3 g of potassium tert-butoxide, 0.08 g of lithium 2-aminocaproate, continuously stir at 65 °C for 140 min, filter, and dry to obtain modified fumed silica.

[0069] The preparation method of the rare earth terbium phenanthroline complex mentioned above is:

[0070] Mix 35 g of 5-amino-phenanthroline with 55 g of terbium triacetate hydrate, 280 g of distilled water, and 18 g of ammonia water, stir in a reaction kettle at 65 °C for 3 hours, distill off the water, and dry to obtain the rare earth terbium phenanthroline complex.

[0071] The antioxidant mentioned above is antioxidant A.

[0072] The accelerator mentioned above is accelerator PZ.

[0073] The vulcanizing agent mentioned above is bis(diethylthiophosphoryl) trisulfide.

[0074] The vulcanization temperature mentioned above is 135 °C, the pressure is 3.5 MPa, and the time is 35 min.

[0075] Example 4

[0076] A preparation method of a rubber-plastic blend brake pad, and its operation steps are:

[0077] S1: Weigh 20 g of rubber and 80 g of plastic, add them to an open mill for mixing for 15 min, and the roll temperature is 150 °C;

[0078] S2: Continuously add 10 g of reinforcing agent, 0.5 g of stearic acid, 1 g of zinc oxide, 0.3 g of antioxidant, 0.3 g of accelerator, 0.3 g of sulfur, and 1 g of vulcanizing agent, and continue to knead for 20 min at a roll temperature of 60 °C. After kneading evenly, let it stand for 25 h;

[0079] S3: Put the kneaded material on a flat vulcanizer for vulcanization to obtain a rubber-plastic blend brake pad.

[0080] The rubber mentioned above is nitrile rubber.

[0081] The plastic mentioned above is polyvinyl chloride.

[0082] The reinforcing agent is modified fumed silica, and its modification method is as follows:

[0083] Add 8 g of silane coupling agent KH560 to 1500 g of ethanol, then add 150 g of fumed silica, continuously stir at 50 °C for 70 min, then add 0.3 g of rare earth terbium phenanthroline complex, 3.5 g of potassium tert-butoxide, and 0.1 g of lithium 2-aminocaproate, continuously stir at 70 °C for 150 min, filter, and dry to obtain modified fumed silica.

[0084] The preparation method of the rare earth terbium phenanthroline complex mentioned above is as follows:

[0085] 40 g of 5-amino-phenanthroline, 70 g of terbium triacetate hydrate, 300 g of distilled water, and 20 g of ammonia water are stirred in a reaction kettle at 70 °C for 4 hours, the water is distilled off, and dried to obtain the rare earth terbium phenanthroline complex.

[0086] The antioxidant mentioned above is antioxidant D.

[0087] The accelerator mentioned above is accelerator M.

[0088] The vulcanizing agent mentioned above is selenium diethyldithiocarbamate.

[0089] The vulcanization temperature is 140 °C, the pressure is 4 MPa, and the time is 40 min.

[0090] Comparative Example 1

[0091] As a comparative example, in this example, except that the fumed silica is not modified, the others are the same as in Example 1.

[0092] Comparative Example 2

[0093] As a comparative example, in this example, except that the rare earth terbium phenanthroline complex is not added, the others are the same as in Example 1.

[0094] Comparative Example 3

[0095] As a comparative example, in this example, except that lithium 2-aminocaproate is not added, the others are the same as in Example 1.

[0096] Performance test

[0097] The friction coefficient and wear rate were tested according to GB5763—1998, and the test temperature was 300 °C.

[0098] Table 1: Test results

[0099] Coefficient of friction <![CDATA[Wear rate × 10 7 / [cm 3 ·(N·m) -1 > Example 1 0.36 0.57 Example 2 0.37 0.56 Example 3 0.37 0.54 Example 4 0.38 0.53 Comparative Example 1 0.31 1.13 Comparative Example 2 0.33 0.88 Comparative Example 3 0.34 0.75

[0100] Through the data analysis of the above examples and comparative examples, the modified fumed silica prepared by the present invention can effectively improve the wear resistance of brake pads.

[0101] For those not covered above, the prior art shall apply.

Claims

1. A method for preparing a rubber-plastic blended brake pad, the operating steps of which are: S1: Weigh 10-20 parts of rubber and 60-80 parts of plastic by weight, add them to an open mill and mix for 10-15 minutes at a roller temperature of 110-150°C; S2: Continue to add 5-10 parts of reinforcing agent, 0.1-0.5 parts of stearic acid, 0.5-1 parts of zinc oxide, 0.1-0.3 parts of antioxidant, 0.1-0.3 parts of accelerator, 0.1-0.3 parts of sulfur, 0.5-1 parts of vulcanizing agent, continue to mix for 10-20 minutes, the roller temperature is 50-60 ° C, after mixing evenly, park for 20-25 hours; S3: placing the mixed materials on a flat vulcanizer for vulcanization to obtain a rubber-plastic blended brake pad; The reinforcing agent is modified fumed silica, which is prepared by reacting silane coupling agent KH560, silica, rare earth terbium o-phenanthroline complex and 2-amino adipate lithium.

2. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The rubber is EPDM rubber or nitrile rubber.

3. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The plastic is high-density polyethylene or polyvinyl chloride.

4. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The reinforcing agent is modified fumed silica, and the modification method is as follows: According to weight, 4-8 parts of silane coupling agent KH560 are added to 1000-1500 parts of ethanol, followed by adding 100-150 parts of white carbon black, stirring continuously for 30-70 minutes at 40-50° C., then adding 0.03-0.3 parts of rare earth terbium o-phenanthroline complex, 1.5-3.5 parts of tert-butyl potassium, 0.01-0.1 parts of 2-aminoadipate lithium, stirring continuously for 100-150 minutes at 60-70° C., filtering, and drying to obtain modified white carbon black.

5. The method for preparing a rubber-plastic blended brake pad according to claim 4, characterized in that: The preparation method of the rare earth terbium o-phenanthroline complex is: According to weight, 20-40 parts of 5-amino-o-phenanthroline, 35-70 parts of terbium triacetate hydrate, 200-300 parts of distilled water, and 10-20 parts of ammonia water are stirred in a reaction kettle at 50-70° C. for 2-4 hours, the water is distilled off, and the rare earth terbium-o-phenanthroline complex is obtained by drying.

6. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The antioxidant is one of antioxidant AW, antioxidant RD, antioxidant A, antioxidant 4010, antioxidant 4010NA, antioxidant H and antioxidant D.

7. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The accelerator is one of accelerator TMTD, accelerator TMTM, accelerator PZ, accelerator EZ, accelerator ZBX, accelerator ZIP, accelerator DM and accelerator M.

8. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The vulcanizing agent is one of dimorpholine disulfide, N, N'-dicaprolactam disulfide, bis(diethylthiophosphoryl) trisulfide, dimorpholine tetrasulfide, and selenium diethyldithiocarbamate.

9. The method for preparing a rubber-plastic blended brake pad according to claim 1, characterized in that: The vulcanization temperature is 120-140° C., the pressure is 3-4 MPa, and the time is 20-40 minutes.