An annularly shaped structure serves as a support and seal when pushed out on a ramp. A continuous seal in a groove is used on one or two sides to enhance sealing. A separate annular structure for sealing can be disposed adjacent to the shape having alternating longitudinal slots so that each structure is targeted to a different purpose. The structures disintegrate when made of a disintegrating material such as for example a controlled electrolytic material (CEM) so that removal of the barrier can occur after a treating operation such as fracturing where many such barriers are deployed. The slots have enlarged holes at their ends to reduce stress concentration that can lead to cracking.