Method and system for zonal isolation

A method of deploying a completion device into a wellbore for zonal isolation, comprising:

• running the completion device into the wellbore, wherein the completion device comprises:
• an elastomer circumferentially disposed around a tubular, the elastomer having a main sealing segment and at least one activation segment axially extending a length from the main sealing segment at opposing ends, wherein each activation segment has an exposed end;
• an impermeable membrane circumferentially encasing the elastomer to prevent an influx of wellbore fluids into the elastomer except at the exposed ends of the at least one activation segment;
• and
• a protective exterior;
• swelling the elastomer by absorbing the wellbore fluids through the exposed ends, wherein swelling occurs axially along the length of the at least one activation segment toward the main sealing segment;
• expanding the impermeable membrane and protective exterior in response to the swelling;
• and
• swelling the main sealing segment by absorbing the wellbore fluids therein, wherein the main sealing segment is unswelled until the wellbore fluids have permeated the length of the at least one activation segment.

A swell packer, comprising:

• a high-swell elastomer circumferentially disposed around a tubular, the elastomer having a main sealing segment with at least one activation segment axially extending a length from the main sealing segment, wherein the at least one activation segment has an exposed end and a radial cross-section smaller than a radial cross-section of the main sealing segment;
• an impermeable membrane circumferentially encasing the elastomer except at the exposed end, wherein the impermeable membrane is configured to prevent an influx of wellbore fluids into the elastomer when it is not swelled except at the exposed end;
• and
• a protective exterior configured to shield the impermeable membrane from wellbore damage as the completion device is being run into the wellbore, wherein the main sealing segment is unswelled until the wellbore fluids have permeated the length of the at least one activation segment.