RADIATION-INDUCED IONIC POLYMERIZATION OF ISOPRENE

Journal Article · Fri Sep 01 04:00:00 EDT 1961 · J. Polymer Sci.

DOI:https://doi.org/10.1002/pol.1961.1205415915· OSTI ID:4837899

Tabata, Y; Shimozawa, R; Sobue, H

The gamma -ray induced polymerization of isoprene was investigated in the temperature range of -78 deg to 40 deg C. The following variables were studied: the dependence of polymerization rate on temperature; the effects of DPPH and pyridine on the polymerization at various temperatures; the dependence of the polymerization rate on dose rate at -78 deg and 20 deg C; and the structure of the polyisoprenes obtained by various temperatures. Although the Arrhenius plot of the polymerization rate did not yield a linear relation, the total polymerization rate was successfully separated into radical and ionic contributions. The polymerization rate was proportional to the square root of dose rate at 20 deg C, whereas it was proportional to the first power of the dose rate at -78 deg C. The structure of polyisoprene prepared at -78 deg C is closely similar to that of cationically polymerized polyisoprene. The partially ionic mechanism of the radioinduced polymerization of isoprene was elucidated in the investigation. It was concluded that a cationic mechanism is operative at low temperatures whereas a radical mechanism predominates at higher temperatures. (auth)

• Research Organization: Japanese Assn. for Radiation Research on Polymers, Tokyo
• NSA Number: NSA-15-032203
• OSTI ID: 4837899
• Journal Information: J. Polymer Sci., Journal Name: J. Polymer Sci. Vol. Vol: 54
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACTIVATION ENERGY
ALKENES
ARRHENIUS PLOT
CATIONS
CHEMISTRY
CONFIGURATION
DPPH
FREE RADICALS
GAMMA RADIATION
INDUCTION
IONS
ISOPRENE
LOW TEMPERATURE
ORGANIC NITROGEN COMPOUNDS
POLYMERIZATION
POLYMERS
PREPARATION
PYRIDINES
RADIATION DOSES
RADIATIONS
REACTION KINETICS
TEMPERATURE