Thermosetting PDLCs: Cure, morphology and thermo-optical response

Two thermosetting matrices based, respectively, on an unsaturated polyester resin and a bifunctional epoxy resin were employed to prepare Polymer Disp ersed Liquid Crystal (PDLC) systems. A molecular, morphological and thermo- optical characterisation of these systems is presented. The unsaturated pol yester based system was found to be phase-separated at all compositions. Im age analysis demonstrated morphological features suitable to achieve intere sting thermo-optical properties, particularly for the composition containin g 40 wt % of LC. The epoxy based system was found to be miscible before cur ing at all compositions. A phase separation occurred upon curing for LC con tents higher than 40 wt %. In this composition range also this system behav es as an efficient thermo-optical switch.