XPS analysis (ESCA) of the surface composition of poly(styrene/2-hydroxyethyl methacrylate) microspheres produced by emulsifier-free emulsion polymerization

摘要: Polymer microspheres composed of various compositions styrene and 2-hydroxyethyl methacrylate (HEMA) were produced by batch emulsifier-free emulsion polymerization. The HEMA content at the surface, [HEMA] s , powdered freeze-drying was determined both quantitativeC1s/O1s analysis andC1s peak shape x-ray photoelectron spectroscopic spectra. When in microsphere, p less than about 5 mole%, values two different methods showed good agreement. At [HEMA]p above mole %, [HEMA]s first method 15 % greater those second. They a similar tendency with being higher e.g., when 1 11 %. intensity satellite due to theπ→π* transition benzene ring component decreased an increase zero . These results indicate that is localized surface.