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Title: From precursors to non-oxide ceramics: Pyrolytic mechanisms studied by NMR

Abstract

The pyrolysis of a poly ethylsilazane was studied using a CO{sub 2}-laser beam heated solid state MAS-NMR probe head. Chemical structures of the intermediate stages could be identified. The analogy of the pyrolysis evolution for the following two different methods could be shown: (A) in an inert gas furnace conventionally prepared and (B) laser irradiated in the NMR probe head under magic-angle spinning (MAS) conditions. Samples prepared by method A were studied by {sup 29}Si MAS-NMR and samples prepared by method B were studied with an appropriate cross polarization time by {sup 29}Si CP-MAS-NMR. Both experiments showed the same mechanisms for the pyrolysis as the polymer is transformed into a Si{sub 3}N{sub 4}/C ceramic.

Authors:
;  [1]; ;  [2]
  1. Univ. of Stuttgart (Germany). Inst. for Nonmetallic Inorganic Materials
  2. Max-Planck-Inst. for Polymer Research, Mainz (Germany)
Publication Date:
OSTI Identifier:
470941
Report Number(s):
CONF-951155-
ISBN 1-55899-313-4; TRN: IM9722%%64
Resource Type:
Book
Resource Relation:
Conference: Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 27 Nov - 1 Dec 1995; Other Information: PBD: 1996; Related Information: Is Part Of Covalent ceramics III -- Science and technology of non-oxides; Hepp, A.F. [ed.] [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center]; Kumta, P.N. [ed.] [Carnegie Mellon Univ., Pittsburgh, PA (United States)]; Sullivan, J.J. [ed.] [MKS Instruments, Andover, MA (United States)]; Fischman, G.S. [ed.] [Food and Drug Administration, Rockville, MD (United States)]; Kaloyeros, A.E. [ed.] [Univ. of Albany, NY (United States)]; PB: 499 p.; Materials Research Society symposium proceedings, Volume 410
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; SILICON NITRIDES; PYROLYSIS; MICROSTRUCTURE; COMPOSITE MATERIALS; GRAPHITE; ORGANOMETALLIC COMPOUNDS; AMORPHOUS STATE; LASER RADIATION; NUCLEAR MAGNETIC RESONANCE; EXPERIMENTAL DATA

Citation Formats

Sigmund, W.M., Aldinger, F., Feike, M., and Spiess, H.W. From precursors to non-oxide ceramics: Pyrolytic mechanisms studied by NMR. United States: N. p., 1996. Web.
Sigmund, W.M., Aldinger, F., Feike, M., & Spiess, H.W. From precursors to non-oxide ceramics: Pyrolytic mechanisms studied by NMR. United States.
Sigmund, W.M., Aldinger, F., Feike, M., and Spiess, H.W. 1996. "From precursors to non-oxide ceramics: Pyrolytic mechanisms studied by NMR". United States. doi:.
@article{osti_470941,
title = {From precursors to non-oxide ceramics: Pyrolytic mechanisms studied by NMR},
author = {Sigmund, W.M. and Aldinger, F. and Feike, M. and Spiess, H.W.},
abstractNote = {The pyrolysis of a poly ethylsilazane was studied using a CO{sub 2}-laser beam heated solid state MAS-NMR probe head. Chemical structures of the intermediate stages could be identified. The analogy of the pyrolysis evolution for the following two different methods could be shown: (A) in an inert gas furnace conventionally prepared and (B) laser irradiated in the NMR probe head under magic-angle spinning (MAS) conditions. Samples prepared by method A were studied by {sup 29}Si MAS-NMR and samples prepared by method B were studied with an appropriate cross polarization time by {sup 29}Si CP-MAS-NMR. Both experiments showed the same mechanisms for the pyrolysis as the polymer is transformed into a Si{sub 3}N{sub 4}/C ceramic.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1996,
month =
}

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