화학공학소재연구정보센터
학회 한국고분자학회
학술대회 2004년 봄 (04/09 ~ 04/10, 고려대학교)
권호 29권 1호, p.51
발표분야 고분자 구조 및 물성
제목 Surface Forces Apparatus (SFA) Studies on n-Octadecyltriethoxysilane Self-Assembled Monolayers on Untreated and Plasma-Treated Mica
초록 Prehydrolyzed n-octadecyltriethoxysilane (OTE) molecules were self-assembled as a monolayer on both untreated and argon/water vapor plasma-treated mica. The properties and stability of these monolayers have been qualitatively and quantitatively investigated with a surface forces apparatus (SFA) under various environmental conditions.
The interaction force between the OTE monolayers immersed in water showed that plasma treatment reduced the range of the steep short-range repulsion and motivated the water vapor studies. The humidity tests revealed a substantial monolayer swelling in the untreated case at 95 %RH or higher but there was no swelling in the plasma treated case. Furthermore, adhesive force measurements as a function of variations in environmental conditions such as temperature, relative humidity, contact time, and high stress showed that the plasma treated OTE monolayer appears to be more stable than the untreated monolayer in high humidities. In dry conditions both monolayers are molecularly smooth, well ordered and highly compact as well as mechanically robust and tenacious. Finally, the thickness compressibility studies in both dry and humid conditions suggested that the OTE phase state for both the plasma treated and untreated cases is pseudo-crystalline. Further, these studies suggested that the monolayer on both plasma treated and untreated mica does not fully cover the entire surface and likely exists as two very discrete phase states composed of large crystalline polymerized OTE domains and somewhat hydrophilic gaseous regions.
The results from several different SFA experiments strongly indicates the OTE-SAM is covalently attached at least partially to the plasma treated mica while the monolayer weakly physisorbs to the untreated mica surface. Accordingly, due to the covalent connection, the OTE-SAM on plasma treated mica is more stable particularly in highly humid or even completely wet environments although it is thought the monolayer does not fully cover the mica surface.
저자 Sungsoo Kim
소속 Department of Soil
키워드 n-octadecyltriethoxysilane; surface forces apparatus
E-Mail