HNBR compositions with very high filler levels having excellent processability and resistance to aggressive fluids
View Patent ↗The present invention relates to an elastomeric composition containing a nitrile rubber, preferably hydrogenated, and a filler. Compositions according to the present invention have high filler levels, excellent processability, and very good resistance to aggressive fluids and fuels compared to known HNBR compositions.
1. An elastomeric composition comprising a hydrogenated nitrile rubber (HNBR) and a carbon black filler, wherein the filler is present in an amount of 200 to 500 parts per hundred rubber and wherein the hydrogenated nitrile rubber has a Mooney viscosity of a maximum 55 (ML1+4 @ 100° C.).
2. The composition according to claim 1 , wherein the hydrogenated nitrile rubber has a Mooney viscosity below 30 (ML(1+4)@ 100° C.).
3. The composition according to claim 2 , wherein the hydrogenated nitrile rubber has a Mooney viscosity below 10 (ML(1+4) @ 100° C.).
4. The composition according to claim 1 , wherein the filler is present in an amount in the range of from 250 to 350 phr.
5. The composition according to claim 1 , wherein the hydrogenated nitrile rubber is carboxylated.
6. A composition according to claim 1 , wherein the hydrogenated nitrile rubber has an acrylonitrile content (ACN) greater than 39%.
7. A composition according to claim 6 , wherein the hydrogenated nitrile rubber has an acrylonitrile content (ACN) greater than 43%.
8. A composition according to claim 6 , wherein the hydrogenated nitrile rubber is fully saturated and contains less than 1% of residual double bonds.
9. An article comprising the composition according to claim 1 , wherein the article has excellent processability and heat resistance of fluids and fuels.