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What are the causes and solutions of embrittlement of insulating rubber sheet?

人气:463 发表时间:2021-04-13

When people create and invent electricity, it benefits people, but because of some power consumption risks, people's assets and personal safety are threatened. After that, people created and invented the insulating rubber plate, which can insulate the electric layer, so that people's personal safety has been greatly ensured! It has certain air permeability resistance, moisture resistance, heat insulation, when it has a defect is not anti embrittlement, do you know what factors will cause embrittlement of insulating rubber sheet? How to maintain it?
Advantages of raw material rubber of insulating rubber sheet are introduced in detail
1. It has very good ductility, and its elastic mold is 3-5mpa
2. Rubber is a kind of crystalline rubber, which will produce crystal under external force. The self fixation is very large and the mean value is high. The content is very large, so it is endowed with high impact toughness.
3. Because of its wide content, it has a very good production and processing performance. It is easy to mix with filler and other rubber, to carry out injection molding, press out and other mechanical manufacturing and adhesive forming.
4. It has good air permeability resistance, moisture resistance, cold resistance, dielectric strength and heat insulation characteristics.
5. There is no optical functional group in the molecular structure chain, so it is a kind of non-polar rubber. Only resistant to some polar solvents. So the wear resistance is very poor. It has good acid resistance, but not strong alkali resistance.
The reasons for embrittlement of insulating rubber sheet are as follows
1. Oxygen in rubber is reflected by the dispersed chain of rubber molecular structure, and the molecular structure chain is broken or too much chemical cross-linking, resulting in the change of rubber properties. Chemical action is one of the key reasons for rubber embrittlement.
2. The organic chemical specificity of reactive oxygen species and reactive oxygen species is much higher than that of oxygen species, and they are more destructive. They also break the molecular structure chain, but the effect of reactive oxygen species on rubber varies with whether the rubber is deformed or not. When the rubber is used for deformation, cracks perpendicular to the effective orientation of the in-situ stress occur. That is to say, "active oxygen cracking", when the rubber is used for deformation, only the surface layer is transformed into air oxide film without cracking.
3. The elevated temperature can cause catalytic cracking or thermochemical crosslinking of rubber. But the basic or active effect of heat. It is a common phenomenon of embrittlement hot oxygen embrittlement to increase the rate of oxygen diffusion and active redox reaction, so as to accelerate the redox reaction rate of rubber.
4. The less light wave, the greater kinetic energy. UV light with high kinetic energy can destroy rubber. Apart from the fact that UV light can immediately cause the rupture of molecular structure chain and chemical crosslinking of rubber, the rubber can digest and absorb solar energy and cause the dispersion group, which can cause and accelerate the whole process of air oxidation chain reaction. Ultraviolet light has the effect of heating. Another characteristic of light efficiency is that it grows on the surface of oak. For the specimens with high adhesive content, reticular cracks will occur on both sides, which means "smooth surface cracks".
5. Under the constant effect of mechanical equipment in-situ stress, the rubber molecular structure will be broken, the components will be dispersed, the air oxidation chain reaction will be caused, and the whole process of organic chemistry will be generated. The whole process of mechanical equipment breaking molecular structure chain and mechanical equipment active air oxidation. Which one will prevail depends on the standard. In addition, it is very easy to cause active oxygen cracking under the effect of in-situ stress.
6. The function of water has two levels. Rubber is easy to be destroyed when it is drenched in wet and cold air or soaked in water. It is because the water-soluble chemicals and cold water functional groups in rubber are extracted and dissolved by water. It is caused by hydrolysis reaction or digestion and absorption. Especially in the replacement effect of water immersion and air exposure, it will accelerate the destruction of rubber. However, under certain conditions, water can not destroy the rubber, and even slow down the embrittlement.
7. Other effective factors for rubber include organic chemicals, metal ions, high-energy radiation sources, electricity and microorganisms.
Methods to avoid embrittlement of insulating rubber sheet:
Because the embrittlement of rubber is a complicated comprehensive chemical change process, and it is impossible to avoid the occurrence of rubber embrittlement, appropriate countermeasures can be adopted to slow down the speed of rubber embrittlement, so as to increase the service life of rubber.
The key measures to prevent embrittlement are physical safety protection method and organic chemical safety protection method. Physical safety protection method is to minimize the interaction between rubber and various embrittlement factors, such as selecting surface coating or solution, adding light shielding agent, adding paraffin, etc. Organic chemical safety protection method is to add some chemicals to avoid or slow down the development of rubber embrittlement reaction, such as adding acrylamine or phenolic compounds Organic Chemical rubber antioxidant.