A potentially biodegradable polyamide (poly(imino-3, 3＇-dithiodipropionylimino-2, 2＇-dithiodiethyl), -(NHCOCH2CH2-S-S-CH2CH2CONHCH2CH2-S-S-CH2CH2)(n)-, PIDI) was prepared by interfacial condensation between 3, 3＇-dithiodipropionic acid and cystamine. PIDI showed an electrochemical response due to reduction of disulfide bonds in the polymer chain and re-oxidation of the produced thiolate anions, Graphite-dispersed PIDI composites were also prepared by using a high speed stirrer and showed high capacity and good cyclability under continuous cycling conditions. Degradation of PIDI was investigated in various pH buffer solutions. Weight loss of PIDI was about 10% for 10 days and 40% for 90 days in pH 5 buffer solution at 37 degrees C.