Decryption of ceramic silicone rubber (2)


At present, the main components of ceramic silicone rubber include the following parts:


1. raw rubber


Methyl vinyl silicone rubber is mainly used. High temperature vulcanized vinyl terminated methyl vinyl silicone rubber can also be used, i.e. dimethylsiloxane methyl vinyl siloxane copolymer with dimethylvinyl siloxane as the end sealing agent. This kind of silicone rubber can be vulcanized with addition vulcanization system. The vulcanizate has high tear strength and low compression set, which is suitable for fire-resistant silicone rubber sealing strip. If a material with better ablation resistance is needed, phenylsilicone rubber or methylphenylvinyl silicone rubber can be selected.


2. Reinforcing filler


White carbon black is used, mainly by gas phase method or precipitation method. The surface treatment of silica can improve the strength and hydrophobicity of silicone rubber vulcanizate. Surface treatment agents include silane coupling agent, octamethylcyclotetrasiloxane, etc.


3. Ceramic filler


At present, the ceramic filler added by the ceramic silicone rubber is generally a new type of environmental friendly inorganic filler material. The low melting point glass powders fr01 and fr02 developed by Anmi micro have the physical characteristics of high temperature melting, high viscosity, and then vitrification or vitrification. The low melting point glass powders matching the temperature are added in the raw materials of the flame-retardant silicone rubber wires and cables in advance after high temperature impact Finally, a protective layer will be formed on the metal surface, which is suitable for expansion and metal, with adjustable color, oxidation resistance, reduction resistance, acid and alkali resistance and super weather resistance.


4. Structural control agent


In order to restrain the "structure" of silicone rubber compound reinforced by fumed silica and ensure the processing performance, structural control agent needs to be added. Generally, hydroxy silicone oil is used (hydroxy content is 0.06-0.12).


5. Heat stabilizer


D100 heat stabilizer developed by Anmi micro nano is a new type of environmental friendly inorganic heat stable functional powder material, which is the base material of stable white material. D100 has many functions, such as heat radiation resistance, light radiation resistance, high thermal conductivity, increasing toughness, improving deformation, shrinkage ratio and yellowing resistance.


6. Other ingredients


According to different application scope and functional requirements, there are some other functional components in the actual formula, including curing agent, colorant, foaming agent, cosolvent, etc.


The main application of ceramic silicone rubber is the fire-resistant wire and cable of medium and low voltage, in order to ensure the power on safety in the process of fire. Therefore, it is not difficult to understand the enthusiasm of the cable industry for the urgent development and application of new fire-resistant insulating material ceramic silicone rubber. The production equipment of ceramic silicone rubber compound is the same as that of ordinary silicone rubber. The compound has good extrusion and molding properties. It can be extruded and vulcanized into wires and cables directly by using silicone rubber wire and cable equipment. Without adding equipment, the production cost can be greatly reduced.


Ceramic silicone rubber has rubber elasticity at room temperature, and will not be brittle and fall off like mica tape after burning. It can be tested by spray and vibration. Considering that in recent years, many major fires in many major civil buildings are related to wires and cables, and the demand for fire-resistant cables in civil buildings is very large, at present, ceramic silicone rubber medium and low-voltage fire-resistant cables will have a great development.


Source: Qichen, Guangdong