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  • 1 Toyama University Department of Chemical and Biochemical Engineering, Faculty of Engineering Gofuku 930 Toyama-shi
  • | 2 Toyama University Faculty of Education Gofuku 930 Toyama-shi Japan
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Abstract  

The pyrolysis of trimethylsilyl derivatives of saccharides (1) was investigated by DTA-TG, MS, GC/MS and TG-GC/MS. The DTA-TG/DTG curves showed that the pyrolysis of 1 occurred in one stage. The exothermic peaks were due to sublimation or thermal decomposition by vaporization. The cleavage mechanism by electron impact of 1 was classified into four categories: 1) stepwise elimination of the side-chain, 2) cleavage of the side-chain, 3) cleavage of the pyranose ring, and 4) cleavage of the pyranose ring and side-chain at the same time. The mass-spectrum for 1 revealed the main common four fragment ions, such asm/z 73, 191, 204 and 217, with cleavage of the pyranose ring. These fragment ions were detected with a similar retention time in the gas cromatogram by GC/MS or TG-GC/MS. The retention time for 1 increased in the sequence aldopentose<ketohexose<aldohexose. This result indicates that the trimethylsilyl derivatives are thermally stable. Subsequently, the pyrolysis regime for 1 obeyed apparent 1/2-order kinetics and their apparent activation energy was estimated as 75–100 kJ/mole.