Rubber composition capable of resisting expansibility of synthetic brake fluid of motor vehicle

Abstract

The invention relates to a rubber composition capable of resisting expansibility of synthetic brake fluid of a motor vehicle. The composition comprises the following components: ternary ethylene propylene diene monomer with low mooney viscosity, liquid ethylene propylene diene monomer, magnesium oxide, magnesium oxide, age resister MB, age resister 4010NA, fast extruding carbon black N550, high-modulus semi-reinforcing carbon black N774, kieselguhr, low-molecular-weight polyisobutylene PB1300, cross-linking agent DCP, assistant cross-linking agent TMPT and sulphur. Due to the utilization of the composition, the hardness change after thermal ageing (150 DEG C*168h) is +6.8 Shore A, the compression set (140 DEG C*24h*25 percent) is 29 percent, the volume expansion change rate in DOT4 brake fluid (70 DEG C*72h and 120 DEG C*72h) is 0.86 percent and 1.02 percent, a sample and a packing leather are soaked in the DOT4 brake fluid for 72h at temperature of 120 DEG C, the expansion change rate of the end diameter and the lip diameter of the packing leather is within 3.0 percent, and the expansion change rate of the end diameter and the lip diameter of the packing leather after resisting the brake fluid in a pipe is within 2.5 percent. The composition provided by the invention can meet the requirement of compatibility of the rubber in the brake fluid of a GB12981-2003 motor vehicle andthe requirement of change rate of the end diameter and the lip diameter of the rubber after resisting the brake fluid in an HG2865-1997 motor vehicle.

Description

technical field [0001] The invention relates to a rubber composition, in particular to a rubber composition resistant to swelling of motor vehicle synthetic brake fluid. Background technique [0002] Automobile brake fluid, also known as brake oil or brake fluid, is composed of base oil or base fluid and various additives. It is a functional liquid used to transmit pressure in the hydraulic braking system of automobiles and make the wheel brakes achieve the braking effect. . There are three types of brake fluid, ① castor oil-alcohol type: it is prepared with refined castor oil and ethanol at a ratio of 1:1. In cold regions, the brake fluid formulated with 34% castor oil, 13% glycerol (glycerol), and 53% ethanol can still guarantee normal braking at about -35°C, but the boiling point is low, which is prone to air resistance. ②Synthetic type: It is made of ether, alcohol, ester, etc. mixed with lubricant, anti-oxidation, anti-rust, anti-rubber swelling and other additives. I...

AI Technical Summary

Problems solved by technology

In cold regions, the brake fluid formulated with 34% castor oil, 13% glycerol (glycerin), and 53% ethanol can still guarantee normal braking at around -35°C, but the boiling point is low, and it is easy to produce air resistance.

②Synthetic type: It is made of ether, alcohol, ester, etc. mixed with lubricant, anti-oxidation, anti-rust, anti-rubber swelling and other additives. It has good performance and the working temperature can be as high as 150 ℃, but the price is higher

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