NOVEL FUNCTIONAL POLYMERS - POLY(DIMETHYLSILOXANE)-POLYAMIDE MULTIBLOCK COPOLYMER .8. SURFACE STUDIES OF ARAMID-SILICONE RESIN BY MEANS OF XPS, STATIC SIMS, AND TEM

The surface structures of solvent-cast films with aramid-poly(dimethyl siloxane) (poly(dimethylsiloxane) = PDMS) multiblock copolymers (PASs) that contained 8, 14, 24, 41, and 71 wt % of PDMS were characterized by angular-dependent X-ray photoelectron spectroscopic (XPS) measureme nts, static secondary ion mass spectrometric (SSIMS) measurements, and transmission electron microscopic (TEM) observations. The results of angular-dependent XPS measurement elucidated that the surface concentr ation of the PDMS segments was much higher than that in bulk and furth er increased with a decrease in the sampling depth. In particular, the Si/C ratios that were determined by XPS at a 10 degrees takeoff angle in PAS films that contained more than 24 wt % PDMS were almost the sa me as that in the PDMS homopolymer. From the results of SSIMS measurem ent, the outermost surfaces of all of the PAS films were found to be c ompletely covered with a PDMS segment even if the PDMS content was onl y 8 wt % in bulk. In addition, we visually confirmed the surface enric hment of the PDMS segment by TEM observation. The free surfaces of all PAS films were predominantly covered with a PDMS thin layer, although the microphase-separated structures in bulk were different according to the PDMS content in PAS.