A static and dynamic study of the mechanical properties of electron beam cured PDLC films

This paper reports a study of static and dynamic mechanical properties of electron beam (EB) cured polymer dispersed liquid crystals. These systems consist of micron-sized droplets dispersed in a solid polymer matrix. They are prepared according to the polymerization induced phase separation process initiated by exposure to electron radiation. A difunctional monomer Tripropylene Glycol Diacrylate in short TPGDA is used with the eutectic liquid crystal mixture E7 having a nematic to isotropic transition temperature at 60degreesC. Strong effects are found on Young modulus and rubbery state modulus in terms of the EB dose and the liquid crystal concentration. As the concentration of small molecules increases, these mechanical parameters drop significantly together with the glass transition temperature T-g of the polymer showing a plasticizing effect. The results for T-g are confirmed by DSC thermograms in terms of liquid crystal concentration and EB dose.