Precise Synthesis and Surface Characterization of End‐Functionalized Polystyrene with Perfluoroalkyl Group via Ionic Bond Formation of Diethylamino End‐Group with Perfluoroalkylcarboxylic Acid

Abstract

Well‐defined polystyrene end‐functionalized with N,N‐diethylamino group (PS‐NEt2) is prepared by a living anionic polymerization of styrene, followed by an end‐capping reaction with a 1,1‐diphenylethylene derivative bearing with the corresponding functional group. The PS‐NEt2 is applied for the reaction with C8F17COOH in order to introduce the ionic‐bonded C8F17 group, i.e., C8F17COO−N+H(C2H5)2 at the polymer chain end. Surface characterization of the resulting polymer film is performed by an X‐ray photoelectron spectroscopy and a contact angle measurement. These results clearly show that the C8F17COO−N+H(C2H5)2 end‐group concentrates at the top of film surface similar to the original C8F17 group. The ionic‐bonded C8F17COOH is found to be removed by a treatment of the film surface with methanol. Moreover, the C8F17COO−N+H(C2H5)2 end‐group that remained inside film appears at the top of film surface by annealing the methanol‐treated film, indicating the surface reconstruction by environmental changes. image