Abstract
Self-assembly had been widely researched recently. Self-assembly is the process by which molecular components adopt a defined arrangement without guidance from an outside source, and aggregate to a specific structures or pattern. L-cysteine or D-cysteine was first introduced to backbone of polyanilines via the CRS reaction to obtain derivatized polyanilines (Pan-Cys). The Pan-Cys can act as building blocks and is self-assembled in to many instresting hierarchical structures included fibril nano-stuctures, polymeric particle, and two dimentional flake stucture through non-covalent interactions such as electrostatic interaction, hydrogen bonding, hydrophobic interactions and van der waals interactions. We also found the formation of an intriguing helical aggregation when Pan-L-Cys/NMP was cast on Pt coated silica wafer. Especially the size over 500 nm would presented in left-handed helix. However Pan-D-Cys would formed in right-handed helix. As for anticorrosion, Pan coated and Pan-SBu coated steel plates have been studied with electrochemical potentiodynamic polarization methods and electrochemical impedance spectroscopy (EIS). Pan-SBu displayed a better anti-corrosion efficiency in comparison with its parent unsubstituted Pan. The results were in line with the expected property changes after the addition of a hydrophobic and electron donating substituent to the polymer backbone. Moreover, Pan-SBu coated steel plates after being solvent-annealed by acetonitrile, showed much surperior anti-corrosion protection. Such treatment help reduce the pinhole and defect of the film and greatly enhance the barrier property of Pan-SBu coated steel .