M. Laus et D. Ferri, DYNAMIC-MECHANICAL BEHAVIOR OF A SIDE-CHAIN LIQUID-CRYSTALLINE POLYACRYLATE, Journal of polymer science. Part B, Polymer physics, 34(6), 1996, pp. 1085-1091
The phenomenology of the alpha- and p-relaxation processes in an amorp
hous and a crystallized specimen of a side-chain LC polyacrylate, base
d on the azobenzene mesogenic unit, was investigated by thermal and dy
namic mechanical methods. The activation energy of the beta relaxation
of the crystallized sample is equal to that of the amorphous sample.
The alpha-transition process of the amorphous sample was described by
the WLF equation. In contrast, the Lu-relaxation behavior of the amorp
hous part of the semicrystalline sample was described by a double Arrh
enius law broken at T = T-g. This peculiar behavior has been tentative
ly related to the decrease of the motion characteristic length of the
macromolecules confined in the multidomain structure of the semicrysta
lline state. (C) 1996 John Wiley & Sons, Inc.