operatively arranged to remove the ions from the flow of fluid before exposure to the swellable material application_number US 201213646028 A description a detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the figures referring now to fig1 a system 10 including a tubular or string 12 and a downhole article 14 e g a packer or sealing element disposed thereon is illustrated the downhole article 14 includes for example a base composition and a filter component discussed in more detail below the base composition comprises an elastomeric material and or an absorbent material due to fluid absorption by the absorbent material e g absorption of water brine hydrocarbons etc the article 14 expands or swells to a second configuration shown in fig2 various absorbent materials are known and used in the art for example with respect to water swellable embodiments any so called super absorbent polymer could be used or those marketed by nippon shokubai co ltd under the name aqualic u00ae cs 6s the elastomeric material is included for example to provide a seal against a downhole structure 16 e g a borehole in a subterranean formation 18 shown in fig2 of course the structure 16 could be any other tubing casing liner etc located downhole.