/sup 29/Si nuclear magnetic resonance study of plasma-polymerized hexamethyldisiloxane

Journal Article · Fri Nov 01 04:00:00 EST 1985 · J. Vac. Sci. Technol., A; (United States)

DOI:https://doi.org/10.1116/1.572802· OSTI ID:6407379

Assink, R A; Hays, A K; Bild, R W; Hawkins, B L

The structure of plasma-polymerized hexamethyldisiloxane (PP-HMDSO) was studied by /sup 29/Si nuclear magnetic resonance (NMR) using magic angle spinning and cross-polarization techniques. Spectra of the PP-HMDSO were recorded before and after it had been subjected to successive heat treatments in air at 100, 200, and 300 /sup 0/C. The spectra exhibit major peaks at +11 ppm, -18 ppm, -55 to -64 ppm, and -99 to -106 ppm with respect to tetramethylsilane. These shifts correspond to silicon bonded to one, two, three, and four oxygens, respectively. The broadness of the tri- and tetrafunctional silicon peaks is attributed to SiOH or SiOCH/sub 3/ functional groups in addition to the normal SiOSi moieties. Minor peaks at -5 and -33 ppm are attributed to mono- and difunctional silicons in which one of the methyl groups has been replaced by a hydrogen. As the material is heat treated there is a tendency for the PP-HMDSO to form additional silicon--oxygen bonds. Spectra simulations show that the oxygen content increases from 16 to 30 wt. % during the course of the heat treatment. The silicon to oxygen weight percent ratios measured by NMR spectra simulation and neutron activation analysis are comparable and decrease monotonically as the heat treatment progresses.

• Research Organization: Sandia National Laboratories, Albuquerque, New Mexico 87185
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6407379
• Journal Information: J. Vac. Sci. Technol., A; (United States), Journal Name: J. Vac. Sci. Technol., A; (United States) Vol. 3:6; ISSN JVTAD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360402 -- Polymers & Plastics-- Structure & Phase Studies-- (-1987)
360404* -- Materials-- Polymers & Plastics-- Physical Properties-- (-1987)
CHEMICAL BONDS
ELEMENTS
EVEN-ODD NUCLEI
HEAT TREATMENTS
HIGH TEMPERATURE
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MEDIUM TEMPERATURE
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC COMPOUNDS
ORGANIC POLYMERS
ORGANIC SILICON COMPOUNDS
POLARIZATION
POLYMERS
RESONANCE
SEMIMETALS
SILICON
SILICON 29
SILICON ISOTOPES
SILOXANES
STABLE ISOTOPES