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CN-121699333-B - High-tear-resistance cable material and preparation method thereof

CN121699333BCN 121699333 BCN121699333 BCN 121699333BCN-121699333-B

Abstract

The invention relates to the technical field of cable materials, in particular to a high-tear-resistance cable material and a preparation method thereof. The material takes hydrogenated styrene-butadiene-styrene block copolymer as a matrix and comprises carboxyl-terminated liquid fluororubber microcapsules and polypyrrole-modified layered double hydroxide nano-sheets. The microcapsule core material is released and has interface effect with the nanometer sheet through the dynamic vulcanization process, and the dynamic sacrificial network and the rigid nanometer skeleton interpenetrating structure are constructed in situ in the matrix. The material has both ultrahigh tearing strength (more than or equal to 78 kN/m) and high elongation at break (more than or equal to 400%), and realizes the electrical early warning function of early mechanical damage by utilizing a sensitive conductive network formed by polypyrrole on the surface of the nano sheet. Meanwhile, the material maintains excellent flame retardance, insulativity, heat resistance and processability, and is suitable for cable jackets with high requirements on reliability and intelligence.

Inventors

  • Xue Changkun
  • ZHANG TAO
  • LI YANGBIN

Assignees

  • 成都归壹远航科技有限公司

Dates

Publication Date
20260508
Application Date
20260224

Claims (10)

  1. 1. The high-tear-resistance cable material is characterized by comprising the following raw materials in parts by weight: 40-60 parts of hydrogenated styrene-butadiene-styrene block copolymer; 15-25 parts of carboxyl-terminated liquid fluororubber microcapsule, wherein the wall material of the microcapsule is thermoplastic polyurethane, and the core material is carboxyl-terminated liquid fluororubber; 5-12 parts of polypyrrole-modified layered double hydroxide nano-sheets; 8-15 parts of flame retardant synergist; 2-4 parts of processing aid; 0.5-1.5 parts of stabilizer; 0.5-2 parts of cross-linking agent; The material is prepared by a process comprising dynamic vulcanization, wherein in the dynamic vulcanization process, a core material of the carboxyl-terminated liquid fluororubber microcapsule is released and interacts with the polypyrrole-modified layered double hydroxide nano sheet, and a dynamic sacrifice network and rigid nano skeleton interpenetrating network structure is formed in the hydrogenated styrene-butadiene-styrene block copolymer matrix.
  2. 2. The high-tear-resistance cable material according to claim 1, wherein the flame retardant synergist is aluminum hypophosphite coated zinc borate, the processing aid is an ethylene-vinyl acetate copolymer, the stabilizer comprises a compound of an antioxidant and a light stabilizer, and the crosslinking agent is dicumyl peroxide.
  3. 3. The high tear resistant cable material of claim 2, wherein the raw materials comprise, in parts by weight: 55 parts of hydrogenated styrene-butadiene-styrene block copolymer; 18 parts of carboxyl-terminated liquid fluororubber microcapsule; 6 parts of polypyrrole-modified layered double hydroxide nano-sheets; 10 parts of aluminum hypophosphite coated zinc borate; 3 parts of ethylene-vinyl acetate copolymer; 1 part of antioxidant and light stabilizer compound; 0.8 parts of dicumyl peroxide.
  4. 4. The high tear cable material of claim 1, wherein the material has a tear strength of not less than 78kN/m and an elongation at break of not less than 400% when subjected to a tear stress.
  5. 5. The high tear resistant cable material of claim 1, wherein the material has a damage pre-warning function and a resistivity change of not less than 850% when the gauge elongation of the material reaches 2%.
  6. 6. A process for the preparation of a high tear resistance cable material according to any one of claims 1 to 5, comprising the steps of: s1, dispersing layered double hydroxide nano sheets in water, adding pyrrole monomers and an oxidant for in-situ polymerization reaction, and washing and drying after the reaction is finished to obtain polypyrrole-modified layered double hydroxide nano sheets; S2, adopting an interfacial polymerization method, taking carboxyl-terminated liquid fluororubber as a core material, taking a thermoplastic polyurethane prepolymer as a wall material, forming microcapsules with a core-shell structure, and separating and drying to obtain the carboxyl-terminated liquid fluororubber microcapsules; S3, melting and plasticizing the hydrogenated styrene-butadiene-styrene block copolymer and a processing aid, and then adding a flame retardant synergist, a stabilizer and the polypyrrole modified layered double hydroxide nano sheet prepared in the S1, and mixing and dispersing to obtain a premix; S4, heating the premix, adding the carboxyl-terminated liquid fluororubber microcapsule prepared in the step S2 and the cross-linking agent, and carrying out melt blending and dynamic vulcanization under a shearing force; in the process, the carboxyl-terminated liquid fluororubber microcapsule wall material is melted and the core material is released, the carboxyl-terminated group of the fluororubber microcapsule wall material interacts with the surface of the polypyrrole-modified layered double hydroxide nano sheet, and partial crosslinking is initiated in the hydrogenated styrene-butadiene-styrene block copolymer matrix to form an interpenetrating network structure; and S5, extruding, cooling, granulating and drying the dynamically vulcanized material to obtain cable material particles.
  7. 7. The method for preparing a high tear-resistant cable material according to claim 6, wherein in S1, the in-situ polymerization reaction is performed under ice water bath conditions, and the oxidizing agent is ammonium persulfate.
  8. 8. The method for preparing a high tear resistant cable material according to claim 6, wherein in S2, the interfacial polymerization method comprises: Dissolving carboxyl-terminated liquid fluororubber and thermoplastic polyurethane prepolymer in an organic solvent to serve as an oil phase, dissolving an emulsifier in water to serve as a water phase, dripping the oil phase into the water phase under high-speed shearing to emulsify, and then adding a curing agent to react.
  9. 9. The method for preparing a high tear resistant cable material according to claim 6, wherein in S3, the temperature of melt plasticization is 120-140 ℃, the time of mixing and dispersing is 5-10 minutes, the temperature of dynamic vulcanization in S4 is 160-170 ℃ and the reaction time is 3-8 minutes, and in S5, the processing temperature of extrusion is 150-160 ℃.
  10. 10. The method for producing a high tear resistant cable material according to claim 6, wherein in S3, premixing is performed using an internal mixer, in S4, dynamic vulcanization is performed using an internal mixer, and in S5, granulation is performed using a twin screw extruder.

Description

High-tear-resistance cable material and preparation method thereof Technical Field The invention relates to the technical field of cable materials, in particular to a high-tear-resistance cable material and a preparation method thereof. Background The mechanical properties, in particular the tear resistance, of the cable sheath, which serves as a critical barrier for protecting the internal conductors, directly determine the service life and the safety of the cable under complex conditions (such as dragging, bending, impact). In the fields of robot joints, ocean engineering, mining equipment, smart power grids and the like, extremely high requirements are put on the tear resistance of the cable sheath. Currently, the main technical route for improving the tear resistance of cable jackets is to add a reinforcing phase into a polymer matrix (such as polyvinyl chloride, polyethylene and rubber), and short-cut fibers (such as aramid fibers and glass fibers) and rigid nano particles (such as nano calcium carbonate and silicon dioxide) are common. However, these methods have significant limitations in that fiber reinforcement can increase strength, but often at the expense of flexibility and processing flowability of the material, and the physical interface of the fiber and the matrix is prone to debonding under long-term dynamic stress, resulting in performance decay, while nanoparticle addition presents challenges of difficult dispersion, easy agglomeration, limited increase in tear strength (typically only 20% -50%), and possibly damaging the insulating properties of the material. More importantly, the methods all belong to passive enhancement of performance, the enhancement mechanism is single (such as fiber pull-out and particle blocking crack), and the synergistic jump of the performance cannot be realized. In addition, the existing sheath material has no active sensing capability at all. When the material generates internal microcracks due to fatigue or external damage, any early warning cannot be provided until the crack growth causes insulation failure, and serious electric accidents can be caused. Disclosure of Invention The invention aims to provide a high-tear-resistance cable material and a preparation method thereof, which are used for solving the problems in the background technology. In order to achieve the aim, on the one hand, the invention provides a high-tear-resistance cable material, which is characterized by comprising two components, namely carboxyl-terminated liquid fluororubber microcapsules serving as dynamic sacrificial networks and polypyrrole-modified layered double hydroxide (PPy@LDH) nanosheets serving as rigid nano frameworks, wherein the materials comprise, in parts by weight: 40-60 parts of hydrogenated styrene-butadiene-styrene block copolymer (SEBS), the saturated structure of which provides excellent flexibility, insulation and weather resistance. 15-25 Parts of carboxyl-terminated liquid fluororubber microcapsule, wherein the wall material of the microcapsule is Thermoplastic Polyurethane (TPU), and the core material is vinylidene fluoride liquid fluororubber with active carboxyl. 5-12 Parts of polypyrrole-modified layered double hydroxide (PPy@LDH) nanosheets, and coating a conductive polypyrrole (PPy) layer on the surfaces of the LDH nanosheets by an in-situ polymerization method. 8-15 Parts of aluminum hypophosphite coated zinc borate (AHP@ZB). 2-4 Parts of ethylene-vinyl acetate copolymer (EVA), 0.5-1.5 parts of antioxidant and light stabilizer compound. 0.5-2 Parts of dicumyl peroxide (DCP) as a cross-linking agent for preparing cross-linked materials. According to the invention, TPU wall materials of the carboxyl-terminated liquid fluororubber microcapsule are melted in a dynamic vulcanization stage in the preparation process, the core material is released, the liquid fluororubber is released, the active carboxyl (-COOH) at the tail end of the liquid fluororubber is subjected to strong ion-dipole interaction with metal ions (such as Mg 2+,Al3+) on the surface of a PPy@LDH nanosheet to bond with an interface, the interface is chemically bonded, as a flexible bridge, innumerable rigid nano islands (PPy@LDH) are connected, and a three-dimensional rigid-flexible interpenetrating network structure, namely a dynamic sacrificial network and a rigid nano skeleton system, is formed in an SEBS matrix. Specifically, when the material is subjected to tearing stress, the crack tip first encounters a rigid barrier formed by PPy@LDH nano sheets, so that in order to overcome the high modulus barrier, the crack needs to consume huge energy to deflect or pull out the nano sheets, at the moment, the liquid fluororubber flexible bridge connecting the nano sheets becomes an energy dissipation area of a core, and the energy is efficiently absorbed and dissipated through the intense stretching, sliding, plastic deformation and even breaking of partial chemical bonds of a molecular chain of t