SURFACE-STRUCTURE OF BLEND FILMS OF STYRENE ACRYLONITRILE COPOLYMER AND POLY(METHYL METHACRYLATE)(PMMA) OR HYDROLYZED PMMA/

The compatibility and the surface structure of blends of poly(styrene- co-acrylonitrile) (SAN) with either poly (methyl methacrylate) (PMMA) or hydrolyzed PMMA (H-PMMA) were studied in terms of film thickness, i nteraction, and surface free energy difference on the basis of X-ray p hotoelectron spectroscopy (XPS), attenuated total reflection Fourier t ransform IR spectroscopy and atomic force microscopy. The. XPS measure ment showed that the surface enrichment of (PMMA/SAN) blends with diff erent AN contents of SAN and with different carboxyl acid contents of PMMA was dependent on the molecular interaction, the surface free ener gy difference between components and the sample preparation history. I t was found that the compatibility of H-PMMA and SAN was reduced with increasing carboxyl acid content of PMMA.