Microphase Separation in Poly(Imide Siloxane) Copolymer

Abstract

The comparative analysis of microheterogeneous structure of the surface of films of amorphous aromatic polyetherimide: poly[4, 4'-bis(4''-N-phenoxy)diphenylsulfon]imide of 1,3-bis(3', 4-dicarboxyphenoxy)benzene (PEI) and poly(imide siloxane) block copolymer (PSI) containing PEI blocks and blocks of dimethylsiloxane units was performed according to electron microscopy. It was shown that anisotropy, long-range order, and the correlation length of density fluctuations increase in PSI film as compared to PEI. PSI samples are characterized by asymmetrical biaxial surface texture, as opposed to PEI, which exhibits axial texture. Periodic density oscillations are observed along the directions of axes of PSI structure at the micron scale. The obtained results evidence microphase separation in PSI film caused by spatially oriented contact interactions between the blocks of dimethylsiloxane units.