Patent ID: 7687571

Claim:
A swellable elastomeric material for use in a wellbore comprising: one or more acid grafted elastomers having residual unsaturation; about 0.5 phr to about 5 phr of one or more ethylenically unsaturated organic monomers comprising one or more acids, anhydrides, or salts thereof; about 1 phr to about 10 phr of an inorganic swelling agent selected from the group consisting of alkali- or alkaline earth carbonate in the form of carbonate of beryllium, calcium, strontium, magnesium, potassium, or lithium; about 1 phr to about 10 phr of a vulcanizing agent; and about 15 phr to about 20 phr of a zwitterionic polymer or monomer.