TITLE

Long-time dynamics in poly(dimethylsiloxane) networks studied by deuterium nuclear magnetic resonance

AUTHOR(S)
Sotta, P.; Deloche, B.
PUB. DATE
March 1994
SOURCE
Journal of Chemical Physics;3/15/1994, Vol. 100 Issue 6, p4591
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
A deuterium NMR (nuclear magnetic resonance) method is proposed to investigate long-time correlation of chain orientation in poly(dimethylsiloxane) networks. It is based on the observation of a quadrupolar echo after a Jeener pulse sequence, which is possible owing to the presence of nonzero residual interactions in the system related to local chain orientations. The time evolution of the quadrupolar echo amplitude is calculated in the framework of a slow chain reorientational motion. An experimental result is presented which shows that local orientation is frozen within the time scale investigated, up to 0.3 s.
ACCESSION #
7642866

 

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