화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.366, 1853-1867, 2001
Relaxation processes in isotropic phase of cholesteryl myristate
The paper reports on study of acoustic parameters in isotropic phase of Cholesteryl Myristate within a frequency range from 2 MHz to 7 MHz. it was observed, that in the range of hypersonic frequencies on a background of a relaxation process with a significant dispersion of sound velocity and characteristic frequency dependence of hypersonic absorption another relaxation process appeared. Hence, it is may be assumed that at least three relaxation processes occur in the isotropic phase of CM within the investigated frequency range. First relaxation process (from 1 HHz to 7 HHz), and third relaxation process (from 2 MHz to 22 MHz) are analogous to those observed for the isotropic phase of the nematic MBBA. The second relaxation process observed in the range of hypersonic frequencies is characteristic only for the isotropic phase of CM and it is not observed for nematics. The nature of this relaxation process is discussed.