Analytical Sciences


Abstract − Analytical Sciences, 20(12), 1623 (2004).

Molecular Weight Evaluation of Poly(dimethylsiloxane) on Solid Surfaces Using Silver Deposition/TOF-SIMS
Masae INOUE, Atsushi MURASE, and Motoyasu SUGIURA
Toyota Central R & D Labs., Inc., Nagakute, Aichi 480-1192, Japan
Molecular ions include information about end groups, functional groups and molecular weight. A method for the direct detection of these in the high mass range (m/z > 1000) from poly(dimethylsiloxane) (PDMS) on a solid surface was investigated. It was found that a TOF-SIMS analysis of silver-deposited surfaces (silver deposition/TOF-SIMS) is useful for this purpose. Using the silver-deposition/TOF-SIMS method, silver-cationized quasi-molecular ions were clearly detected from PDMS on solid surfaces, and their structure and molecular weight were evaluated. In addition, their images were observed without the interference of deposited silver. By applying to the analysis of paint defects etc., it was confirmed that this technique is useful to analyze actual industrial materials. Silver-cationized ions were detected not only from PDMS, but also from other organic materials, such as lubricant additives and oils on solid surfaces. Therefore, the silver deposition/TOF-SIMS method was proved to be useful for the analysis of ultrathin substances on solid surfaces.