Silane coupling agent is mainly used as crosslinking agent and tackifier in wires, cables and pipes, which endows the materials with the following properties:
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Enhance thermal deformation stability and mechanical strength of modified materials;
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Improve wet electrical properties of modified materials;
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Improve chemical resistance of modified materials;
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Increase filler addition and improving processability.
Different silane coupling agent can be applied according to the material and requirement of modified cable system. The cable materials suitable for modification with silane coupling agents are mainly polyolefin and elastomer polymers.
Vinyl silanes are the most commonly used crosslinking agents for polyolefin materials, because they can be grafted with polyolefin or copolymerized with olefin at higher temperature and initiator action. The alkoxy functional groups on silanes can undergo intermolecular condensation reaction after hydrolysis in wet environment and polyolefin crosslinking.
In the process of producing silane crosslinked polyolefins, the commonly used vinyl silanes include CFS-027/vinyltrimethoxysilane, CFS-080/vinyltriethoxysilane and CFS-534/vinyltri(2-methoxyethoxy)silane. Among them, CFS-534 has the highest boiling point and is suitable for use at higher processing temperature. The hydrolysis rate of CFS-027 is the fastest and it is suitable for producing silane crosslinked polyethylene in warm water. CFS-080 has a relatively slow hydrolysis rate, and it is suitable for producing crosslinked polyolefin with relatively long storage time.
In the production of low smoke halogen-free cable materials, such as blends of EVA, EVA and polyolefin, EP rubber, EPDM rubber and polyolefin, when flame retardants are aluminum hydroxide (ATH), magnesium hydroxide (MH), calcined clay, calcined talc powder, calcined kaolin, alumina hydrate (AlOH) or aluminum phosphate. Silane coupling agent is often used as the surface modifier of inorganic flame-retardant materials to improve the dispersion of fillers in resins or rubber and the adhesion with resins, and to improve the processability, mechanical properties and thermal stability of the filled substrates.
Besides functional silanes, Co-Formula also offers vinyl silane oligomers and dispersing agent specially designed for wires, cables and pipes. For more details, please consult Co-Formula.