The phenomenology of the alpha- and p-relaxation processes in an amorphous and a crystallized specimen of a side-chain LC polyacrylate, based on the azobenzene mesogenic unit, was investigated by thermal and dynamic 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 amorphous part of the semicrystalline sample was described by a double Arrhenius law broken at T = T-g. This peculiar behavior has been tentatively related to the decrease of the motion characteristic length of the macromolecules confined in the multidomain structure of the semicrystalline state.