Depletion effect in a model lyotropic liquid crystal-theory

(Received 9 August 1993, received in final foret 14 September 1993, accepted 20 October 1993)

Abstract
The effect of added non-adsorbing polymer on the isotropic-nematic phase transition in a model lyotropic liquid crystal - a suspension of hard rods - is studied theoretically. The results indicate that the transition is widened and that polymer is partitioned preferentially into the more dilute isotropic phase. The concentration of polymer where a noticeable effect on the transition starts to occur is predicted to be of the order 5 % of the coil overlap threshold c*.