Elastomeric seal

1. A pressure containment equipment seal comprising an elastomeric composite, said composite comprising an elastomeric polymer and a negative thermal expansion (NTE) filler, the NTE filler having a coefficient of thermal expansion (CTE) lower than −6×10 −6 K −1 within a temperature range of 220-293 K and being present in an amount of 0.01-50 volume % based on the total volume of the elastomeric composite at 20° C., and wherein a surface of the seal is free of the NTE filler and an outer layer of the seal is made of an elastomeric polymer not comprising an NTE filler.

2. The pressure containment equipment seal according to claim 1 , wherein the elastomeric composite constitutes more than 10 volume %, of said seal, based on the total volume of the seal.

3. The pressure containment equipment seal according to claim 1 , wherein the amount of NTE filler is in the range of 1.0-30 volume % based on the total volume of the elastomeric composite at 20° C.

4. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −6×10 −6 K −1 at a temperature within a range of 220-293 K.

5. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −6×10 −6 K −1 over a temperature range of 220-293 K.

6. The pressure containment equipment seal according to claim 1 , wherein the NTE filler is evenly distributed in the elastomeric composite.

7. The pressure containment equipment seal according to claim 1 , wherein the amount of NTE filler in the elastomeric composite decreases or increases over at least one dimension of the seal.

8. The pressure containment equipment seal according to claim 7 , wherein the amount of NTE filler in the elastomeric composite decreases or increases in relation to a distance from the surface of the seal.

9. The pressure containment equipment seal according to claim 7 , wherein the amount of NTE filler decreases in one of a stepwise or a continuous manner.

10. The pressure containment equipment seal according to claim 1 , wherein the elastomeric polymer is a synthetic rubber.

11. The pressure containment equipment seal according to claim 10 , wherein the synthetic rubber is a material selected from the group consisting of NBR (nitrile butadienes), HNBR (hydrogenated nitrile butadienes), FKM (fluoroelastomers), FFKM (perfluoroelastomers), and any combination thereof.

12. The pressure containment equipment seal according to claim 1 , wherein the NTE filler is a material selected from the group consisting of metal tungstates, metal phosphates, metal molybdates, metal vanadates, metal arsenates, metal nickelates, metal oxides, metal nitrides, metal cyanides, magnetic nanocrystalline materials, Invar alloys, and any combination thereof.

13. The pressure containment equipment seal according to claim 1 , wherein the elastomeric composite retracts less than 0.001% over a temperature decrease of 1° C. within a temperature range of −50° C. to +20° C.

14. A method for manufacturing a pressure containment equipment seal, the method comprising:

providing an elastomeric composite comprising an elastomeric polymer and a negative thermal expansion (NTE) filler, the NTE filler having a coefficient of thermal expansion (CTE) lower than −6×10 −6 K −1 within a temperature range of 220-293 K and being present in an amount of 1.0-30 volume % based on the total volume of the elastomeric material at 20° C., and wherein a surface of the seal is free of the NTE filler and an outer layer of the seal is made of an elastomeric polymer not comprising an NTE filler; and

forming the elastomeric composite into a desired shape of the seal.

15. The pressure containment equipment seal according to claim 8 , wherein the amount of NTE filler decreases in one of a stepwise or a continuous manner.

16. The pressure containment equipment seal according to claim 12 , wherein the NTE filler is a material selected from the group consisting of zirconium tungstate (ZrW 2 O 8 ), hafnium tungstate (HfW 2 O 8 ), Zr 2 P 2 WO 12 , Hf 2 P 2 WO 12 , HfMg(WO 4 ) 3 , BiNiO 3 , BiNiO 3 -alloys, CuO-nanocrystals, Cd(CN) 2 , Invar Fe 3 Pt, and any combination thereof.

17. The pressure containment equipment seal according to claim 1 , wherein the elastomeric composite constitutes more than 25 volume % of said seal, based on the total volume of the seal.

18. The pressure containment equipment seal according to claim 1 , wherein the elastomeric composite constitutes more than 50 volume % of said seal, based on the total volume of the seal.

19. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −15×10 −6 K −1 at a temperature within a range of 220-293 K.

20. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −25×10 −6 K −1 at a temperature within a range of 220-293 K.

21. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −30×10 −6 K −1 at a temperature within a range of 220-293 K.

22. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −35×10 −6 K −1 at a temperature within a range of 220-293 K.

23. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −15×10 −6 K −1 over a temperature range of 220-293 K.

24. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −25×10 −6 K −1 over a temperature range of 220-293 K.

25. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −30×10 −6 K −1 over a temperature range of 220-293 K.

26. The pressure containment equipment seal according to claim 1 , wherein the NTE filler has a CTE lower than −35×10 −6 K −1 over a temperature range of 220-293 K.