ISSN:
1435-1536
Schlagwort(e):
Polymeremulsion
;
polymermicrosphere
;
XPSanalysis
;
styrene
;
2-hydroxyethylmethacrylate
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
Notizen:
Abstract Polymer microspheres composed of various compositions of styrene and 2-hydroxyethyl methacrylate (HEMA) were produced by batch emulsifier-free emulsion polymerization. The HEMA content at the surface, [HEMA] s , of the microspheres powdered by freeze-drying was determined by both quantitativeC 1s /O 1s analysis andC 1s peak shape analysis of the x-ray photoelectron spectroscopic spectra. When the HEMA content in the microsphere, [HEMA] p , was less than about 5 mole%, the [HEMA] s values determined by the two different methods showed good agreement. At [HEMA]p above 5 mole %, [HEMA]s values determined by the first method were about 15 mole % greater than those determined by the second. They both showed a similar tendency with the [HEMA] s being higher than the [HEMA] p , e.g., when [HEMA] p was 1 mole %, [HEMA] s was 11 mole %. The intensity of the satellite peak due to theπ→π * transition of the benzene ring of the styrene component decreased with an increase in [HEMA] p , to zero at 5 mole % of [HEMA] p . These results indicate that the HEMA component is localized at the surface.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01410333
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