Vibrational spectroscopy at high pressures. Part 41.—Infrared spectra of acrylonitrile and polyacrylonitrile

Acrylonitrile has been examined visually and by i.r. spectroscopy to 50 kbar. The liquid freezes at ca. 11 kbar. There is a phase transformation in the solid near 27 kbar. Above 10 kbar polyacrylonitrile co-exists with the liquid or solid phases: this polymer has an i.r. spectrum closely similar to that from the product of u.v.-induced polymerisation under ambient conditions.