Filling composition for cables

1. A filling composition comprising:

a selectively hydrogenated isoprene-styrene block copolymer having a structure S-EP with at least 44 wt. % polystyrene content, a total diblock apparent molecular weight of at least 160 kg/mole, the polystyrene block S has a true molecular weight in the range of 60 to 110 kg/mole, and the polyisoprene block (EP) has a true molecular weight in the range of 80-100 kg/mole;

80 wt. % to 96 wt. % of an oil selected from a paraffinic oil, oil-enriched in paraffin, a mineral oil, a Fischer-Tropsch derived oil, a synthetic oil, or mixtures thereof;

optional additives; and

wherein the filling composition has a thixotropic ratio of 2-10, a drop point of at least 200° C., and a cone penetration at 25° C. of less than 400 dmm.

2. The filling composition of claim 1 , wherein the polystyrene block S having a true molecular weight of 70-75 kg/mole.

3. The filling composition of claim 1 , wherein the selectively hydrogenated isoprene-styrene block copolymer is dissolvable in the oil at a temperature of less than 185° C.

4. The filling composition of claim 3 , wherein the selectively hydrogenated isoprene-styrene block copolymer is dissolvable in the oil at a temperature in the range of 125-145° C.

5. The filling composition of claim 1 , wherein the composition has a drop point of at least 210° C.

6. The filling composition of claim 1 , wherein the composition has an oil separation at 100C from 0% to about 2%.

7. The filling composition of claim 1 , wherein the composition has a viscosity at 25° C. and 50/s between about 10,000 to 60,000.

8. The filling composition of claim 1 , wherein the selectively hydrogenated isoprene-styrene block copolymer is present in an amount from 4-20 wt. %, based on the total weight of the composition.

9. The filling composition of claim 1 , wherein the optional additives comprise at least one of a corrosion inhibitor, a colorimetric indicator, an antioxidant, a metal deactivator, a rheology modifier, a hydrocarbon resin, fumed silica, organophillic clay, and combinations thereof.

10. The filling composition of claim 9 , wherein the colorimetric indicator is selected from the group of rare earth salts, lithium salts, alkali salts of dithiozone, a rubeanic acid chelating agent, and mixtures thereof.

11. The filling composition of claim 1 , wherein the oil is a paraffinic oil having more than 90 percent saturates, less than 0.03 percent sulfur and with a viscosity index of 80 to 120.

12. A cable comprising the filling composition of claim 1 , where the filling composition provides protection from water ingress or corrosion.

13. A method for making a filling composition comprising dissolving a selectively hydrogenated isoprene-styrene block copolymer in an oil selected from a paraffinic oil, oil-enriched in paraffin, a mineral oil, a Fischer-Tropsch derived oil, a synthetic oil, or mixtures thereof,

wherein the selectively hydrogenated isoprene-styrene block copolymer having a structure S-EP with at least 44 wt. % polystyrene content, a total diblock apparent molecular weight of at least 160 kg/mole, the polystyrene block S has a true molecular weight in the range of 60 to 110 kg/mole, and the polyisoprene block (EP) has a true molecular weight in the range of 80-100 kg/mole;

wherein the oil is present in an amount of 80 wt. % to 96 wt. %, based on the total weight of the composition; and

wherein the filling composition has a thixotropic ratio of 2-10, a drop point of at least 200° C., and a cone penetration at 25° C. of less than 400 dmm.

14. The method of claim 13 , wherein the oil is a paraffinic oil having more than 90 percent saturates, less than 0.03 percent sulfur and with a viscosity index of 80 to 120, and wherein the selectively hydrogenated isoprene-styrene block copolymer is dissolved in the oil at a temperature of less than 180° C.