Analysis of Polymer Surface Structure by Low-Energy Ion Scatterinq Spectroscopy

Low-energy Ion scattering spectroscopy (LEIS or ISS) Is used to complement angle-resolved X-ray photoelectron (ARESCA or ARXPS) data for various polymer surfaces. ISS analysis of poly(dimethylsiloxane) (DMS), poly(methylphenylsiloxane) (MPS), and poly(dimethylsiloxane) (DPS) showed a nonlinear Increase in C/O ratio with bulk carbon content, Indicative of the shadowing by bulky phenyl rings. The series of stereoregular poly(methyl methacrylates) (PMMA) and atactic PMMA is investigated to illustrate the unique ability of ISS to detect tacticity via differences In functional group shadowing In polymer surface structure. A series of poly(methyl methacrylate)/poly(methacryilc) acid (PMMA/PMAA) random copolymers are investigated to illustrate capabilities to detect compositional changes in polymer surface structure. ESCA data that show no differences in composition or qualitative peak shifts for these systems are also presented. ISS data from siloxane copolymers and blends are investigated to illustrate the effects of surface orientation and microstructure of near-surface regions. ESCA data are used for both systems to be complemented or contrasted by ISS data In the elucidation of surface microstructure especially for block copolymers and blends of DMS and bisphenol A polycarbonate (BPAC).