Accession Number : ADA199098

Title :   Laser Desorption Mass Spectrometry of Substituted Silane High Polymers,

Corporate Author : IBM ALMADEN RESEARCH CENTER SAN JOSE CA

Personal Author(s) : Magnera, T ; Balaji, V ; Sooriyakumaran, R ; Miller, R D ; Michl, J

PDF Url : ADA199098

Report Date : 01 Aug 1988

Pagination or Media Count : 72

Abstract : Laser ablation of a variety of polysilanes at 308 nm using fluences of 150-250 mJ/sq.cm. per pulse, well above the photoablation threshold, is a photothermal process and yields products identical to those obtained in vacuum pyrolysis with a CO2 laser. Unsaturated hydrocarbon products characteristic of the side chains have been identified unequivocally. Silicon-containing products have not been identified individually and it is proposed that they are a mixture of cyclic carbonsilanes, mostly containing no more than two or three silicon atoms linked to each other. A reaction mechanism for the ablation process is proposed and involves no previously unknown reaction steps. The results demonstrate that laser-desorption mass spectrometry will be a good analytical tool for the characterization of this class of polymers. Due to the high volatility of the hydrocarbons, the presence of even quite long side chains on the polymer backbone need not be a source of concern in the applications of the photoablation process. Polysilane laser desorption, Mass spectrometry, Fragments, Desorption mechanism, Silanes. (MJM).

Descriptors :   *DESORPTION, *LASERS, *POLYMERS, *SILANES, ABLATION, HYDROCARBONS, MASS SPECTROMETRY, PHOTOTHERMAL PROPERTIES

Subject Categories : Organic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE