An appointment of a proxy is revocable unless the appointment form or electronic transmission states that it is irrevocable and the appointment is coupled with an interest. Appointments coupled with an interest include the appointment of:
(1) A pledgee;
(2) A person who purchased or agreed to purchase the shares;
(3) A creditor of the corporation who extended it credit under terms requiring the appointment;
(4) An employee of the corporation whose employment contract requires the appointment; or
(5) A party to a voting agreement created under § 47-1A-731.
An appointment made irrevocable under this section is revoked when the interest with which it is coupled is extinguished.