INVESTIGATION OF THE LOW-FREQUENCY MOTIONS IN ISOTACTIC AND ATACTIC POLYPROPYLENE BY NEUTRON INELASTIC SCATTERING

Journal Article · Sun Mar 01 04:00:00 EST 1964 · Journal of Chemical Physics (U.S.)

DOI:https://doi.org/10.1063/1.1725328· OSTI ID:4088156

Safford, G H; Danner, H R; Boutin, H; Berger, M

S>The vibrational spectra between 1000 and 30 cm/sup -1/, derived from measurements of the inelastic scattering of cold neutrons, are presented for isotactic polypropylene at sample temperatures below and above both the glass transition and the melting point. A tentative assignment of the observed modes is suggested. In addition to the skeletal optical modes, the neutron spectra for isotactic polypropylene indicate the existence of two acoustic mode s --- skeletal deformation and skeletal torsion--- with -1/, respectively. As in polyethylene, the modes appear to be strongly influenced by the presence and phase of the disorder in the sample. Similar spectra for atactic polypropylene above and below the glass transition show a much less pronounced structure, although weak bands are observed which correlate well with the skeletal optical modes observed in the isotactic polymer. (P.C.H.)

• Research Organization: Columbia Univ., New York and Brookhaven National Lab., Upton, N.Y.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-013819
• OSTI ID: 4088156
• Journal Information: Journal of Chemical Physics (U.S.), Journal Name: Journal of Chemical Physics (U.S.) Vol. Vol: 40; ISSN JCPSA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CHEMISTRY
DEFORMATION
LATTICES
NEUTRONS
OSCILLATIONS
POLYMERS
PROPYLENE
SCATTERING
SPECTRA