Special low-smoke halogen-free flame retardant cladding layer material for butterfly-shaped introduction cable of access network

Abstract

The invention discloses a special low-smoke halogen-free flame retardant cladding layer material for a butterfly-shaped introduction cable of an access network. The special low-smoke halogen-free flame retardant cladding layer material comprises the following material components in parts by weight: 5-15 parts of high-fused ethylene-vinyl acetate copolymer, 5-15 parts of low-fused ethylene-vinyl acetate copolymer, 5-15 parts of polyethylene, 55-65 parts of fire retardant, 10-20 parts of compatilizer, 2-3 parts of ultra-high molecular weight silicone, and 0.3-0.8 part of anti-oxygen. According to the cladding layer material, a large amount of high-fused ethylene-vinyl acetate copolymer is used in a base material, so that the flowability of the material can be improved, the material has good surfaces in a rapid extruding process; moreover, when the cross section of a rubber-insulated optical cable is 8-shaped, the middle connection seam is smooth and firm because of the good material flowability. In addition, for reducing the curtain coating phenomenon in the rapid extrusion type extruding process, the ultra-high molecular weight silicone master batch, instead of polyethylene wax with a small molecular weight, is used as a lubricant. Furthermore, since the use amount of the compatilizer is increased in the cladding layer material and the fire retardant powder is treated by using a silane coupling agent, the binding property of the cladding layer material with an optical fiber and a reinforcing piece of the material can be enhanced and the optical attenuation degree can be greatly reduced.

Description

technical field [0001] The invention relates to a special low-smoke, halogen-free and flame-retardant cladding layer material for a butterfly-shaped lead-in optical cable for an access network. Background technique [0002] The butterfly-shaped lead-in optical cable for the access network, commonly known as the leather cable, is the most complicated link in the fiber-optic access project, and the indoor wiring close to the user is the most complicated link. wiring needs. The covered cable has a single-core, double-core structure, and can also be made into a four-core structure, that is, the cross-section is 8-shaped, and the strengthening member is located in the center of the two circles. Metal or non-metal structure can be used, and the optical fiber is located at the geometric center of the 8-shaped . The coating layer of the leather cable is mainly low-smoke, halogen-free and flame-resistant fuel. The leather cable is a newly developed product in the past two years, an...

AI Technical Summary

Problems solved by technology

The existing common low-smoke and halogen-free materials mainly use low-melt index ethylene-vinyl acetate copolymer (melt index between 2-8) as the base material, with a little compatibilizer, and low molecular weight polyethylene wax lubricant , there are many disadvantages in this way: First, the leather cable is a thin wire. If it is mass-produced, the extrusion speed is quite high, and the surface of the material is required to be still good under the condition of rapid extrusion. However, the existing low-smoke Since the halogen-free material uses low-melt ethylene-vinyl acetate copolymer as the base material, the fluidity of the material is not good, and the extrusion speed is difficult to increase at a high filling level, and the casting phenomenon is serious; When the cross-section of the optical cable is 8-shaped, due to mold restrictions and other reasons, the requirements for the discharge of the middle joint are very high. Due to the poor fluidity of ordinary low-smoke and halogen-free materials, the material is easy to break at the joint and sticky. The junction strength is too low, the surface is rough, etc.; again, the cladding material is in direct contact with the optical fiber and its reinforcement. If the bond is not strong, the shrinkage will be severe, and it will have a great impact on the attenuation of the optical fiber signal. The existing ordinary low-smoke and halogen-free Only a small amount of compatibilizer is used in the flame retardant cladding material, which makes the signal attenuation of the covered optical cable generally large