A new diamine, 1,1-bis [4-(4-aminophenoxy)phenyl]cyclododecane (BAPCD), bearing flexible ether and bulky pendant cyclododecylidene groups was prepared in three steps from cyclododecanone. The monomer was reacted with six conventional aromatic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization. The poly(amic acid)s obtained had inherent viscosities ranging from 1.10-1.42 dl g(-1). All the poly(amic acid)s could be cast from DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films, except for polymer V-a which was derived from pyromellitic dianhydride. X-ray diffractograms of polyimides indicated all polymers were amorphous except the polymer V-a. Polyimides derived from 4,4＇-sulfonyldiphthalic anhydride and 4,4＇-hexafluoroisopropylidenediphathalic anhydride exhibited excellent solubility in various polar solvents. These polymers showed glass transition temperatures between 259 degrees C and 276 degrees C, and decomposition temperatures at initial and 10% mass loss ranging from 430 degrees C to 483 degrees C and from 504 degrees C to 526 degrees C in nitrogen, respectively. The polyimide films, except V-a, had a tensile strength in the range 76-112 MPa and a tensile modulus in the range 2.1-3.5 GPa.