Accession Number : AD0818735

Title :   VIBRATIONAL SPECTRA OF HIGH POLYMERS.

Descriptive Note : Final technical rept. Jan-Dec 66,

Corporate Author : POLITECNICO DI MILANO (ITALY) IST DI CHIMICA INDUSTRIALE

Personal Author(s) : Zerbi, Giuseppe ; Cortili, Gabriele ; Gussoni, Mariangela ; Piseri, Luigi

Report Date : APR 1967

Pagination or Media Count : 102

Abstract : This report is divided into three separate units. The first part discusses the chain conformations of polyvinylidene fluoride as derived from its vibrational spectrum. From the study of the infrared spectrum it is shown that, under suitable conditions, polyvinylidene fluoride can exist at least with two different conformations: a planar zig-zag Poly (A) type chain, and a Poly (TATB) type chain with a glide plane. In the second work, experimental and theoretical evidence has been collected from the infrared spectrum on the existence of short helical segments of isotactic polypropylene in the liquid state. Normal coordinate calculations on a simplified model as well as the experimental study of ethylene-propylene copolymers were the theoretical and experimental sources on which the interpretation was based. The third work deals with the theoretical study of molecular vibrations of a polymer chain. A method for the calculation of dispersion curves of a chain isolated from its neighbors has been proposed. A computer program has been written and calculations have been carried out on several polymers. Dispersion curves and the corresponding density distributions have been obtained for polyethylene and deuterated polyethylene, hexagonal polyoxymethylene and deutero derivative, orthorombic polyoxymethylene and isotactic polypropylene. (Author)

Descriptors :   (*POLYMERS, VIBRATION), INFRARED SPECTROSCOPY, INFRARED SPECTRA, MOLECULAR STRUCTURE, POLARIZATION, INTENSITY, BIBLIOGRAPHIES.

Subject Categories : Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE