Brake hose with low expansion performance

Abstract

The invention relates to the technical field of hoses, and provides a brake hose with low expansion performance, the brake hose with low expansion performance sequentially comprises an inner rubber layer, a first enhancement layer, a middle rubber layer, a second enhancement layer and an outer rubber layer from inside to outside, the inner rubber layer and the outer rubber layer are made of the same materials, and the inner rubber layer and the outer rubber layer are made of ethylene propylene diene monomer materials. The ethylene propylene diene monomer material is prepared from the following raw material components: ethylene propylene diene monomer, brominated butyl rubber, modified carbon black, first white carbon black, first zinc oxide, first stearic acid, an anti-aging agent, a flow promoter, a first plasticizer, a first adhesive, a first vulcanizing agent and a first accelerant; the modified carbon black is obtained by modifying carbon black with an aliphatic polyurethane acrylic acid copolymer dispersion; the middle rubber layer is made of a styrene-butadiene rubber and natural rubber composite material; the first reinforcing layer is formed by weaving polyester impregnated wires; and the second reinforcing layer is formed by weaving vinylon threads. According to the technical scheme, the problem that the tensile strength of the outer rubber layer is insufficient in the prior art is solved.

Description

Technical Field

[0001] This invention relates to the field of hose technology, and more specifically, to a brake hose with low expansion performance. Background Technology

[0002] Low-expansion brake hoses are key flexible connectors in the braking systems of various motor vehicles and rail transit vehicles. Their core function is to transmit braking media such as brake fluid or compressed air during braking, achieving effective transmission of braking pressure and ensuring precise response of the braking mechanism. As the automotive industry continues to demand higher requirements for braking response speed, braking accuracy, and adaptability to extreme environments, even higher performance requirements are being placed on low-expansion brake hoses.

[0003] The outer rubber layer of the brake hose, as its outer protective structure, directly determines the overall service life and reliability of the hose. Current technology commonly uses carbon black as a reinforcing agent to improve the strength of the outer rubber layer. However, carbon black tends to agglomerate in the rubber matrix, hindering the improvement of the outer rubber layer's performance. This weakens the long-term stable protection of the inner reinforcing layer and may accelerate the overall performance degradation of the hose due to external environmental damage. Therefore, developing a brake hose with high tensile strength and low expansion performance is of great significance. Summary of the Invention

[0004] This invention proposes a brake hose with low expansion performance, which solves the problem of insufficient tensile strength of the outer rubber layer in related technologies.

[0005] The technical solution of the present invention is as follows: This invention proposes a brake hose with low expansion performance. The low-expansion brake hose comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer. The inner and outer rubber layers are made of the same material, specifically ethylene propylene diene monomer (EPDM) rubber. The EPDM rubber material comprises the following components by weight: 100 parts EPDM rubber, 5-10 parts brominated butyl rubber, 60-80 parts modified carbon black, 10-20 parts first silica, 5-7 parts first zinc oxide, 1-3 parts first stearic acid, 2-4 parts antioxidant, 1-2 parts flow aid, 8-12 parts first plasticizer, 5-8 parts first binder, 1-2 parts first vulcanizing agent, and 3-5 parts first accelerator. The modified carbon black is obtained by modifying carbon black with an aliphatic polyurethane acrylic copolymer dispersion. The raw materials of the middle rubber layer include the following components by weight: 100 parts of styrene-butadiene rubber, 50-60 parts of natural rubber, 100-120 parts of carbon black, 20-40 parts of second silica, 5-8 parts of second plasticizer, 6-10 parts of second zinc oxide, 1-3 parts of second stearic acid, 1-3 parts of second vulcanizing agent, 2-5 parts of second accelerator, and 3-5 parts of second adhesive; The first reinforcing layer is woven from polyester impregnated yarn; the second reinforcing layer is woven from vinylon yarn.

[0006] As a further technical solution, the raw material of the modified carbon black includes carbon black and aliphatic polyurethane acrylic copolymer dispersion in a mass ratio of 100:7~9.

[0007] As a further technical solution, the preparation method of the modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to a solvent and dispersed evenly, carbon black is added and mixed, and then filtered and dried to obtain modified carbon black.

[0008] As a further technical solution, the mixing temperature is 50~60℃, and the mixing time is 1~2h.

[0009] As a further technical solution, the brominated butyl rubber is composed of a first brominated butyl rubber and a second brominated butyl rubber, wherein the first brominated butyl rubber and the second brominated butyl rubber have different Mooney viscosities.

[0010] As a further technical solution, the Mooney viscosity of the first brominated butyl rubber is 32, and the test conditions are ML(1+8) and 125°C; the Mooney viscosity of the second brominated butyl rubber is 46, and the test conditions are ML(1+8) and 125°C.

[0011] This invention improves the elongation at break of the outer rubber layer of a brake hose with low expansion performance by compounding a first brominated butyl rubber with a Mooney viscosity of 32 and a second brominated butyl rubber with a Mooney viscosity of 46. The first brominated butyl rubber with a Mooney viscosity of 32 has lower intermolecular chain forces and better flowability, which can compensate for the uneven dispersion and processing difficulties caused by the high viscosity of the second brominated butyl rubber. The second brominated butyl rubber with a Mooney viscosity of 46 has longer molecular chains and relatively higher viscosity, providing stronger molecular chain entanglement and compensating for the insufficient entanglement of the first brominated butyl rubber. This system, combining long and short chains and complementing high and low viscosity, forms a more complete and uniform network cross-linked structure after vulcanization, optimizing the slippage and entanglement ability of the molecular chains within the outer rubber layer material, thereby improving the elongation at break of the outer rubber layer of the brake hose with low expansion performance.

[0012] As a further technical solution, the mass ratio of the first brominated butyl rubber to the second brominated butyl rubber is 1:2~3, preferably 1:2.5.

[0013] As a further technical solution, the antioxidant includes one or more of antioxidant MB, antioxidant CZ, and antioxidant RD.

[0014] As a further technical solution, the flow aid is flow aid LD-200.

[0015] As a further technical solution, the first plasticizer and the second plasticizer each independently include one or more of dioctyl sebacate, dioctyl terephthalate, and diisononyl phthalate.

[0016] As a further technical solution, the first adhesive and the second adhesive each independently include one or both of adhesive A and adhesive RS.

[0017] As a further technical solution, both the first and second vulcanizing agents are sulfur.

[0018] As a further technical solution, the first accelerator and the second accelerator each independently include one or more of accelerator CZ, accelerator BZ, and accelerator TMTD.

[0019] The working principle and beneficial effects of this invention are as follows: This invention improves the tensile strength of the outer rubber layer of a low-expansion brake hose by adding carbon black modified with an aliphatic polyurethane-acrylic acid copolymer dispersion to the outer rubber layer. The amino groups in the aliphatic polyurethane-acrylic acid copolymer dispersion can form hydrogen bonds with the hydroxyl groups on the surface of the carbon black to form a polymer coating layer, which can effectively prevent the agglomeration of the carbon black itself and allow the carbon black to be more uniformly dispersed in the EPDM rubber matrix, giving full play to the reinforcing effect of the carbon black and thus improving the tensile strength of the outer rubber layer of the low-expansion brake hose. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] In the following examples and comparative examples: Ethylene propylene diene monomer (EPDM) rubber, model: 4725P, manufacturer: Dow Chemical Company, USA; The first brominated butyl rubber has a Mooney viscosity of 32, and the test conditions are ML(1+8), 125℃. The model is 2211, and the manufacturer is ExxonMobil. The Mooney viscosity of the second brominated butyl rubber is 46. The test conditions are ML(1+8), 125℃. The model is 2244 and the manufacturer is ExxonMobil. Styrene-butadiene rubber, model: 1502, manufacturer: Jilin Petrochemical Branch of China National Petroleum Corporation; Natural rubber, type: SCRWF, manufacturer: Shanghai Jiuqing Chemical Co., Ltd. Carbon black, average particle size: 40nm; The silica is precipitated silica with an average particle size of 30 nm. The sulfur is sulfur 80; Flow aid LD-200, manufacturer: Wenzhou Longou Plastics Technology Co., Ltd.; Aliphatic polyurethane acrylic copolymer dispersion, 39% solids content, model: E-129, manufacturer: Covestro Polymers (China) Co., Ltd.

[0022] Example 1 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 5 parts of brominated butyl rubber, 2 parts of antioxidant RD, 5 parts of adhesive A, 5 parts of zinc oxide, 1 part of stearic acid, and 1 part of flow aid LD-200 at 40°C for 60 seconds. Then add 8 parts of dioctyl sebacate, 60 parts of modified carbon black, and 10 parts of silica and continue mixing for 3 minutes. Then add 1 part of sulfur and 3 parts of accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 50 parts natural rubber, 3 parts adhesive A, 6 parts zinc oxide, and 1 part stearic acid at 30°C for 60 seconds. Then add 5 parts dioctyl sebacate, 100 parts modified carbon black, and 20 parts silica and continue mixing for 3 minutes. Then add 1 part sulfur and 2 parts accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 50°C for 2 hours. After filtration and drying, modified carbon black is obtained. The mass-volume ratio of carbon black to water is 1g:10mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100:7.

[0023] Example 2 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 7.

[0024] Example 3 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 10 parts of brominated butyl rubber, 4 parts of antioxidant RD, 8 parts of adhesive A, 7 parts of zinc oxide, 3 parts of stearic acid, and 2 parts of flow aid LD-200 at 50°C for 40 seconds. Then add 12 parts of dioctyl sebacate, 80 parts of modified carbon black, and 20 parts of silica and continue mixing for 5 minutes. Then add 2 parts of sulfur and 5 parts of accelerator CZ and mix at 110°C for 2 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 60 parts natural rubber, 5 parts adhesive A, 10 parts zinc oxide, and 3 parts stearic acid at 40°C for 60 seconds. Then add 8 parts dioctyl sebacate, 120 parts modified carbon black, and 40 parts silica and continue mixing for 3 minutes. Then add 3 parts sulfur and 5 parts accelerator CZ and mix at 110°C for 2 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 60°C for 1 hour, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1g:10mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100:7.

[0025] Example 4 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 50: 4.

[0026] Example 5 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 9.

[0027] Example 6 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is a second brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 7.

[0028] Example 7 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is composed of a first brominated butyl rubber and a second brominated butyl rubber in a mass ratio of 1:2. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 7.

[0029] Example 8 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is composed of a first brominated butyl rubber and a second brominated butyl rubber in a mass ratio of 1:2.5. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 7.

[0030] Example 9 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 7 parts of brominated butyl rubber, 3 parts of antioxidant RD, 7 parts of adhesive A, 6 parts of zinc oxide, 2 parts of stearic acid, and 1.5 parts of flow aid LD-200 at 45°C for 50 seconds. Then add 10 parts of dioctyl sebacate, 70 parts of modified carbon black, and 15 parts of silica and continue mixing for 4 minutes. Then add 1.5 parts of sulfur and 4 parts of accelerator CZ and mix at 105°C for 3 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is composed of a first brominated butyl rubber and a second brominated butyl rubber in a mass ratio of 1:3. S2. Mix 100 parts styrene-butadiene rubber, 55 parts natural rubber, 4 parts adhesive A, 8 parts zinc oxide, and 2 parts stearic acid at 35°C for 50 seconds. Then add 7 parts dioctyl sebacate, 110 parts modified carbon black, and 30 parts silica and continue mixing for 4 minutes. Then add 2 parts sulfur and 4 parts accelerator CZ and mix at 105°C for 4 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to water and dispersed evenly, carbon black is added and mixed at 55°C for 1.5 h, then filtered and dried to obtain modified carbon black, wherein the mass-volume ratio of carbon black to water is 1 g: 10 mL, and the mass ratio of carbon black to aliphatic polyurethane acrylic copolymer dispersion is 100: 7.

[0031] Comparative Example 1 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 5 parts of brominated butyl rubber, 2 parts of antioxidant RD, 5 parts of adhesive A, 5 parts of zinc oxide, 1 part of stearic acid, and 1 part of flow aid LD-200 at 40°C for 60 seconds. Then add 8 parts of dioctyl sebacate, 60 parts of carbon black, and 10 parts of silica and continue mixing for 3 minutes. Then add 1 part of sulfur and 3 parts of accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 50 parts natural rubber, 3 parts adhesive A, 6 parts zinc oxide, and 1 part stearic acid at 30°C for 60 seconds. Then add 5 parts dioctyl sebacate, 100 parts carbon black, and 20 parts silica and continue mixing for 3 minutes. Finally, add 1 part sulfur and 2 parts accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance.

[0032] Comparative Example 2 A brake hose with low expansion performance comprises, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer, wherein the inner rubber layer and the outer rubber layer are made of the same material; A method for preparing a brake hose with low expansion properties includes the following steps: S1. Mix 100 parts of EPDM rubber, 5 parts of brominated butyl rubber, 2 parts of antioxidant RD, 5 parts of adhesive A, 5 parts of zinc oxide, 1 part of stearic acid, and 1 part of flow aid LD-200 at 40°C for 60 seconds. Then add 8 parts of dioctyl sebacate, 60 parts of modified carbon black, and 10 parts of silica and continue mixing for 3 minutes. Then add 1 part of sulfur and 3 parts of accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain inner and outer rubber layers. The brominated butyl rubber is the first brominated butyl rubber. S2. Mix 100 parts styrene-butadiene rubber, 50 parts natural rubber, 3 parts adhesive A, 6 parts zinc oxide, and 1 part stearic acid at 30°C for 60 seconds. Then add 5 parts dioctyl sebacate, 100 parts modified carbon black, and 20 parts silica and continue mixing for 3 minutes. Then add 1 part sulfur and 2 parts accelerator CZ and mix at 100°C for 5 minutes. Transfer the mixture to a two-roll mill for thin sheeting and cool to room temperature to obtain the rubber compound with the middle layer. S3. Extrude the inner rubber layer material and coat it onto the outside of a mandrel mold with an outer diameter of 3.2 mm to obtain an inner rubber layer with a thickness of 3.0 mm; S4. The polyester impregnated yarn is braided onto the outside of the inner rubber layer to obtain the first reinforcing layer; S5. Extrude the rubber compound of the intermediate layer and coat it on the outside of the first reinforcing layer to obtain a 0.5mm intermediate layer; S6. Weave the vinylon yarn onto the outside of the middle rubber layer to obtain the second reinforcing layer; S7. Extrude the rubber material of the outer layer to cover the outside of the second reinforcing layer to obtain a 2.5mm outer layer. Demold to obtain a brake hose with low expansion performance. The preparation method of modified carbon black includes the following steps: after adding silane coupling agent KH-550 to water and dispersing it evenly, carbon black is added and mixed at 50°C for 2 hours. After filtration and drying, modified carbon black is obtained. The mass-volume ratio of carbon black to water is 1g:10mL, and the mass ratio of carbon black to silane coupling agent KH-550 is 100:7.

[0033] Experimental Example 1 The outer rubber layer of the brake hoses with low expansion performance prepared in Examples 1-9 and Comparative Examples 1-2 was tested according to the following method: The tensile strength and elongation at break of the outer rubber layer were determined according to the method specified in GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The tensile speed was 500 mm / min, the test temperature was 23±2℃, and the specimen was a type 1 dumbbell-shaped specimen. The test results are shown in Table 1 and Table 2 below. Table 1 Performance test results of Examples 1-5 and Comparative Examples 1-2

[0034] The tensile strength of Examples 1-5 is higher than that of Comparative Examples 1-2, indicating that the present invention improves the tensile strength of the outer rubber layer of the brake hose with low expansion performance by adding carbon black modified by aliphatic polyurethane acrylic copolymer dispersion.

[0035] Table 2 Performance test results of Examples 2 and 6-9

[0036] The elongation at break of Examples 7-9 is higher than that of Examples 2 and 6, indicating that the present invention improves the elongation at break of the outer rubber layer of the brake hose with low expansion performance by adding a first brominated butyl rubber with a Mooney viscosity of 32 and a second brominated butyl rubber with a Mooney viscosity of 46.

[0037] Experimental Example 2 The low-expansion brake hoses prepared in Examples 1-3 were tested according to the following method: The volumetric expansion value of the brake hose was determined according to the method specified in GB / T 7127.1-2000 "Brake hose assemblies for hydraulic braking systems of road vehicles using non-petroleum-based brake fluid". The test pressure was 6.9 MPa, the pressure increase rate was 0.10 MPa, and the test medium was water. The test results are shown in Table 3 below.

[0038] Table 3 Performance test results of Examples 1-3

[0039] In Examples 1-3, the expansion amount at 6.9 MPa was less than 1.08 cm. 3 / m indicates that the brake hose of the present invention has a low volume expansion value.

[0040] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A brake hose with low expansion performance, characterized in that, The low-expansion brake hose consists of, from the inside out, an inner rubber layer, a first reinforcing layer, a middle rubber layer, a second reinforcing layer, and an outer rubber layer. The inner and outer rubber layers are made of the same material, specifically ethylene propylene diene monomer (EPDM) rubber. The EPDM rubber material comprises the following components by weight: 100 parts EPDM rubber, 5-10 parts brominated butyl rubber, 60-80 parts modified carbon black, 10-20 parts first silica, 5-7 parts first zinc oxide, 1-3 parts first stearic acid, 2-4 parts antioxidant, 1-2 parts flow aid, 8-12 parts first plasticizer, 5-8 parts first adhesive, 1-2 parts first vulcanizing agent, and 3-5 parts first accelerator. The modified carbon black is obtained by modifying carbon black with an aliphatic polyurethane acrylic copolymer dispersion; The raw materials of the middle rubber layer include the following components by weight: 100 parts of styrene-butadiene rubber, 50-60 parts of natural rubber, 100-120 parts of carbon black, 20-40 parts of second silica, 5-8 parts of second plasticizer, 6-10 parts of second zinc oxide, 1-3 parts of second stearic acid, 1-3 parts of second vulcanizing agent, 2-5 parts of second accelerator, and 3-5 parts of second adhesive; The first reinforcing layer is woven from polyester impregnated yarn; the second reinforcing layer is woven from vinylon yarn.

2. The brake hose with low expansion performance according to claim 1, characterized in that, The modified carbon black raw material includes carbon black and aliphatic polyurethane acrylic copolymer dispersion in a mass ratio of 100:7~9.

3. A brake hose with low expansion performance according to claim 1, characterized in that, The method for preparing the modified carbon black includes the following steps: after the aliphatic polyurethane acrylic copolymer dispersion is added to a solvent and dispersed evenly, carbon black is added and mixed, then filtered and dried to obtain the modified carbon black.

4. A brake hose with low expansion performance according to claim 3, characterized in that, The mixing temperature is 50~60℃, and the mixing time is 1~2h.

5. A brake hose with low expansion performance according to claim 1, characterized in that, The brominated butyl rubber is composed of a first brominated butyl rubber and a second brominated butyl rubber, and the first brominated butyl rubber and the second brominated butyl rubber have different Mooney viscosities.

6. A brake hose with low expansion performance according to claim 5, characterized in that, The Mooney viscosity of the first brominated butyl rubber was 32, and the test conditions were ML(1+8) and 125°C; the Mooney viscosity of the second brominated butyl rubber was 46, and the test conditions were ML(1+8) and 125°C.

7. A brake hose with low expansion performance according to claim 5, characterized in that, The mass ratio of the first brominated butyl rubber to the second brominated butyl rubber is 1:2~3.

8. A brake hose with low expansion performance according to claim 1, characterized in that, The antioxidant includes one or more of antioxidants MB, antioxidant CZ, and antioxidant RD.

9. A brake hose with low expansion performance according to claim 1, characterized in that, The first plasticizer and the second plasticizer each independently include one or more of dioctyl sebacate, dioctyl terephthalate, and diisononyl phthalate.

10. A brake hose with low expansion performance according to claim 1, characterized in that, The first adhesive and the second adhesive each independently include one or both of adhesive A and adhesive RS.

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