Cable and method for producing the cable
A cable is used, in particular, as an underwater cable and contains a central element, which is surrounded by a cable sheath. The cable sheath has an inner hydrophobic sheath layer made of a first plastic and an outer sheath layer applied to same and made of a different plastic to the inner sheath layer. A polyolefin-type plastic is used for the inner sheath layer and one of the sheath layers, in particular the inner sheath layer is chemically functionalized, and a sealed connection is formed between the two sheath layers.
1. A cable, comprising:
a central element; and
a cable sheath having an inner hydrophobic sheath ply formed from a first plastic and an outer sheath ply being applied to said inner hydrophobic sheath ply and formed from a plastic different from that of said inner hydrophobic sheath ply, wherein a polyolefinic plastic is used for said inner hydrophobic sheath ply, wherein one of said inner hydrophobic sheath ply or said outer sheath ply is chemically functionalized resulting in a chemically functionalized sheath ply, wherein said outer sheath ply is formed from a polyurethane, and wherein a fluid-tight connection is formed between said inner hydrophobic sheath ply and said outer sheath ply.
2. The cable according to claim 1 ,
further comprising a medium-density polyethylene copolymerized with vinylsilane being used for forming said inner hydrophobic sheath ply; and
wherein said polyurethane for forming said outer sheath ply has a catalyst.
3. The cable according to claim 1 , further comprising a silane-modified polyolefinic plastic having silicon-functional groups being used for said chemically functionalized sheath ply.
4. The cable according to claim 3 , wherein a fraction of silanes in said chemically functionalized sheath ply is in a range between 0.1-5.0 wt %.
5. The cable according to claim 1 , further comprising a plastic having a reactive functional group is used for the chemical functionalization.
6. The cable according to claim 5 , wherein a fraction of said reactive functional group in said chemically functionalized sheath ply is in a range between 0.01-3.0 wt %.
7. The cable according to claim 1 , wherein a polyolefin with a blend partner is used for said chemically functionalized sheath ply.
8. The cable according to claim 7 , wherein a fraction of said blend partner is in a range of 1-50 wt %.
9. A cable, comprising:
a central element;
a cable sheath having an inner hydrophobic sheath ply formed from a first plastic and an outer sheath ply being applied to said inner hydrophobic sheath ply and formed from a plastic different from that of said inner hydrophobic sheath ply, wherein a polyolefinic plastic is used for said inner hydrophobic sheath ply, wherein one of said inner hydrophobic sheath ply or said outer sheath ply is chemically functionalized resulting in a chemically functionalized sheath ply, and wherein a fluid-tight connection is formed between said inner hydrophobic sheath ply and said outer sheath ply; and
a catalyst system being incorporated in one of said inner hydrophobic sheath ply and said outer sheath ply in order to form the fluid-tight connection between said inner hydrophobic sheath ply and said outer sheath ply.
10. The cable according to claim 9 , further comprising a polyurethane being used for said outer sheath ply.
11. The cable according to claim 9 , wherein said catalyst system has a Brønsted or a Lewis acid.
12. The cable according to claim 9 , wherein said catalyst system has a sulfonic acid catalyst.
13. The cable according to claim 9 , wherein said catalyst system has an organotin catalyst.
14. The cable according to claim 9 , wherein a fraction of said catalyst system is in a range of 0.1-5.0 wt %.
15. The cable according to claim 1 , wherein said inner hydrophobic sheath ply has a Shore hardness of 45D to 65D and/or said outer sheath ply has a Shore hardness of 70A to 70D.
16. The cable according to claim 1 , wherein the cable has an overall diameter of between 5 mm to 45 mm.
17. The cable according to claim 1 , wherein said inner hydrophobic sheath ply has an inner wall thickness which is between 0.1 mm for a small overall diameter to 1.5 mm for a large overall diameter.
18. The cable according to claim 1 , wherein said outer sheath ply has an outer wall thickness which is between 0.2 mm for a small overall diameter to 2.0 mm for a large overall diameter.
19. A cable comprising:
a central element;
a cable sheath having an inner hydrophobic sheath ply formed from a first plastic and an outer sheath ply being applied to said inner hydrophobic sheath ply and formed from a plastic different from that of said inner hydrophobic sheath ply, wherein a polyolefinic plastic is used for said inner hydrophobic sheath ply, wherein one of said inner hydrophobic sheath ply or said outer sheath ply is chemically functionalized resulting in a chemically functionalized sheath ply, and wherein a fluid-tight connection is formed between said inner hydrophobic sheath ply and said outer sheath ply; and
the cable is pressure-resistant for several 10 bar and resistant to fluctuating pressure stresses.
20. The cable according to claim 1 , wherein at least one of said inner hydrophobic sheath ply or said outer sheath ply has a flame-retardant plastics mixture as said first plastic or said plastic.
21. The cable according to claim 1 , wherein further measures for ensuring the fluid-tightness, such as a separating ply between said inner hydrophobic sheath ply and said outer sheath ply, a swellable nonwoven, or fillers, are eschewed.