Phase Transitions in Suspensions of Rod-Like Colloids Plus Polymers

Phase Transitions in Suspensions of Rod-Like Colloids Plus Polymers 

So far we have considered the phase behaviour of colloidal spheres plus deple-tants. In Chap. 3 we considered the simplest type of depletant, the penetrable hard sphere. We then extended this treatment in Chap. 4 to ideal and excluded volume polymers and in Chap. 5 we considered small colloidal spheres (ineluding mieelles) and colloidal rods as depletants. In this chapter we consider the phase behaviour of mixtures of colloidal rods plus polymeric depletants. For an overview of several types of colloidal rods encountered in practice we refer to [1]. 

Pure hard rod suspensions exhibit interesting phase transitions themselves. Upon concentrating a dilute rod suspension for L/D 3.5 the phase states schematically depicted in Fig. 6.1 will be encountered the isotropic, nematic and smectic liquid states and a crystalline solid state [2-4]. For a description of the various liquid crystalline phases we refer the reader to standard textbooks on liquid crystals such as [5]. We mainly focus on the isotropic and nematic states and it will become clear that adding depletants will strongly affect the isotropic-nematic phase transition. 

Lekkerkerker and R. Tuinier, Colloids and the Depletion Interaction, Lecture Notes in Physics, 833, DOI 10.1007/978-94-007-1223-2 6, 

---