Molecular relaxations in the composites of liquid crystalline cellulose derivatives with poly(acrylic acid)

The molecular relaxation phenomena of the specific polymer composites obtai ned by photopolymerisation of the oriented lyotropic liquid-crystalline sys tems composed of cellulose derivatives dissolved in photopolymerisable acry lic acid are studied. We have investigated the composites based on two cell ulose derivatives, which differ by the length of their side-chains and cons equently by their physical properties. In this work, the molecular relaxations of such anisotropic composites were studied by dielectric relaxation spectroscopy and by thermooptical analysi s. In the dielectric relaxation spectroscopy two representations were analy sed: temperature dependences of dielectric loss epsilon " (T) and of electr ic modulus M " (T). The electric modulus representation is especially conve nient to monitor the relaxations in a high temperature range where the ioni c conductivity dominates the dielectric response.