Multi-layered flexible tube
View Patent ↗A multi-layered tube comprising a first inner polymeric tubular structure, a second foamed polymeric structure containing a plurality of short or long reinforcing elements dispersed therein and, optionally, a third cover layer on the outer surface of the reinforcing layer; and a method for manufacturing the multi-layered hose are disclosed.
1. A flexible tube comprising:
a first tubular structure, said first tubular structure comprising a first polymeric material having an inner circumferential surface providing a path for conveying fluids, and an outer circumferential surface;
a foamed second tubular structure comprising a second polymeric material containing a plurality of reinforcement elements randomly dispersed therein, said second tubular structure having an inner circumferential surface and an outer circumferential surface, the inner circumferential surface of which is adhered to the outer circumferential surface of said first tubular structure; and
a third tubular structure comprising a third polymeric material, said third tubular structure comprising a polymeric material having an inner circumferential surface and an outer circumferential surface, the inner circumferential surface of which is adhered to the outer circumferential surface of said second tubular structure.
2. The hose of claim 1 wherein said plurality of reinforcement elements comprises natural fibers, synthetic fibers, or metal wire, mineral elements, or combinations thereof.
3. The hose of claim 2 wherein said plurality of reinforcement elements comprises natural fibers, synthetic fibers or metal wires having a length of about 0.012 to 2.00 inches and a diameter of about 0.004 to 0.024 inch.
4. The hose of claim 3 wherein said plurality of reinforcement elements are natural or synthetic fibers or metal wires having a length of about 0.012 to 0.050 inches and a diameter of about 0.004 to 0.024 inches.
5. The hose of claim 3 wherein said plurality of reinforcement elements are natural or synthetic fibers selected from the group consisting of nylon fibers, rayon fibers, aramid fibers, cotton fibers, polyester fibers, glass fibers, carbon fibers.
6. The hose of claim 2 wherein said plurality of reinforcement elements comprises wollastonite, glass beads, mica, talc, silica, kaolin, calcium carbonate or mixtures thereof.
7. The hose of claim 1 wherein each of said first tubular structure, said second tubular structure and said third tubular structure is a thermoplastic vulcanizate selected from the group consisting of polyethylene, polypropylene; polyurethane, polyamide, polyphthalamide, ethylene vinyl acetate copolymers, acrylonitrile-butadiene-styrene terpolymers, polyethylene terephthalate, polybutylene terephthalate, polyvinyl chloride, polyphenylene, or polytetrafluoroethylene as a matrix material having, dispersed therein, a plurality of small globules of a cured or partially cured elastomeric material selected from the group consisting of ethylene-propylene-diene monomer, chlorinated polyethylene, chlorinated polypropylene, chlorosulfonated polyethylene, chlorosulfonated polypropylene, styrene-butadiene rubber, nitrile-butadiene rubber, hydrogenated nitrile-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, and acrylic acid ester rubber, said plurality of small globules having a particle size of less than 50 microns.
8. The hose of claim 7 wherein said thermoplastic vulcanizate comprises a thermoplastic polypropylene matrix having dispersed therein a plurality of elastomeric ethylene-propylene-diene monomer (EPDM) globules.
9. The hose of claim 1 wherein at least one of said first tubular structure, and said third tubular structure is foamed.
10. The hose of claim 1 wherein said foamed second tubular structure has a specific gravity of about 0.55 to 0.90.
11. A flexible hose for transporting fluids in an automotive coolant system, said hose comprising:
a first tubular structure having an inner surface and an outer surface, wherein said first tubular structure is a thermoplastic vulcanizate comprising a thermoplastic polypropylene matrix having a plurality of EPDM globules dispersed therein;
a second tubular structure having an inner surface and an outer surface, wherein said inner surface of said second tubular structure is disposed on the outer surface of said first tubular structure, wherein said second tubular structure is a foamed thermoplastic vulcanizate comprising a foamed thermoplastic polypropylene matrix having a plurality of EPDM globules dispersed therein, said second foamed thermoplastic vulcanizate tubular structure further comprising a plurality of reinforcement elements if the form of fibers or wires having a length of about 0.012 inches 0.050 inch and a diameter of about 0.004 to 0.024 inches dispersed therein, wherein said second foamed thermoplastic vulcanizate tubular structure has a specific gravity of about 0.55 to 0.90; and
a third tubular structure around second tubular structure, wherein said third tubular structure is a thermoplastic vulcanizate comprising a thermoplastic polypropylene matrix having a plurality of EPDM globules dispersed therein.
12. The hose of claim 11 wherein said plurality of reinforcement elements are in the form of natural or synthetic fibers selected from the group consisting of nylon fibers, rayon fibers, aramid fibers, cotton fibers, polyester fibers, glass fibers, carbon fibers, or combinations thereof.
13. A flexible hose for transporting fluids in an automotive coolant system, said hose comprising:
a first tubular structure having an inner surface and an outer surface, wherein said first tubular structure is a thermoplastic vulcanizate comprising a thermoplastic polypropylene matrix having dispersed therein a plurality of EPDM globules;
a second tubular structure having an inner surface and an outer surface, said inner surface of said second tubular structure being disposed on the outer surface of said first tubular structure, wherein said second tubular structure is a foamed thermoplastic vulcanizate comprising a thermoplastic polypropylene matrix having a plurality of EPDM globules dispersed therein, said second thermoplastic vulcanizate tubular structure further comprising a plurality of reinforcement minerals selected from the group consisting of wollastonite, glass fibers, carbon fibers, glass beads, mica, talc, silica kaolin, calcium carbonate and mixtures thereof dispersed therein, said foamed second tubular structure has a specific gravity of about 0.55 to 0.90; and
a third tubular structure around said second tubular structure, wherein said third tubular structure is a foamed thermoplastic vulcanizate comprising a foamed thermoplastic polypropylene matrix having a plurality of EPDM globules dispersed therein, said third tubular structure having a specific gravity of about 0.55 to 0.90.
14. The hose of claim 1 further comprising an adhesive material between at least one of said first tubular structure and between said second tubular structure and said third tubular member.