Accession Number : ADA296513

Title :   Optimization of Low Temperature Vitrification for Surface Analysis of Hydrated Hydrogel Polymers.

Descriptive Note : Technical rept.,

Corporate Author : STATE UNIV OF NEW YORK AT BUFFALO DEPT OF CHEMISTRY

Personal Author(s) : Schamberger, Patrick C. ; Gardella, Joseph A., Jr. ; Grobe, George L., III ; Valint, Paul L., Jr

PDF Url : ADA296513

Report Date : SEP 1994

Pagination or Media Count : 55

Abstract : A method for analyzing hydrated hydrogel polymer surfaces in ultra-high vacuum atmospheres has been developed. The materials used for this study were commercially available poly(2-hydroxyethylmethacrylate) (HEMA) based hydrogel polymer ("soft") contact lenses. Application of a temperature controlled sample handling attachment for maintaining liquid nitrogen temperature samples is discussed. Issues such as ample handling, sample preparation, X-ray damage, have been investigated and controlled. Compared to a hydrated surface, specific surface enrichments of various components such as poly(dimethylsiloxane) and poly(N-vinylpyrrolidone) on the dehydrated surface are detected. This is likely due to surface energetics and differences in hydrophobicity/hydrophilicity of the components. jg p.1

Descriptors :   *LOW TEMPERATURE, *SURFACE ANALYSIS, *OPTIMIZATION, *POLYMERS, DAMAGE, X RAYS, HYDRATES, SAMPLING, LIQUID NITROGEN, ATMOSPHERES, ENRICHMENT, HYDROPHOBIC PROPERTIES, ULTRAHIGH VACUUM, SURFACE ENERGY, CONTACT LENSES.

Subject Categories : Polymer Chemistry
      Physical Chemistry
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE