Moreover, such characteristics are interest in many other industrial areas and a further development of the utilization of this polymer may be expected from these studies. Particularly Cellulose derivative polymers are intensively used in pharmaceutical applications to modify the release of drugs in tablets and capsule formulations and to improve their dissolution in the gastrointestinal fluids. This process is called “hydrophilization”. (Kamel, Ali et al. 2008) showed that both low and high viscosity grade cellulose ether polymers can be mixed uniformly, in different proportions, in order to produce matrices with modulated drug release properties. The study of(S. C. NAIK and 1976) confirms
Rheological studies of cellulose derivative are of importance for estimating and understanding on a molecular basis, the function of these components in food systems. Several works were carried to improve the stability of emulsions by adding natural cellulose derivatives to increase the viscosity of the medium (Radi and Amiri 2013), (Yaseen, Herald et al. 2005), to perform and control the texture of foodstuffs, they are also used as thickener, binder, stabilizer suspending and water retaining agent (Mirhosseini, Tan et al. 2008), (Menezes, Marques et al. 2010). The polymer-surfactant interaction has been the subject of several studies. (H. Lauer 1999; L.G.Patruyo 2002) were interested in studying the interaction between HEC and three of its drifts with the SDS; they showed that these interactions lead to phase separation in an intermediate concentration range of SDS and, for higher concentrations of surfactants, when a homogeneous phase has been obtained, these interactions lead to higher apparent shear and expansion viscosities.
The addition of other surfactants eventually reduces hydrophobic interactions due to electrostatic repulsion between the micelles, causing shear viscosities to be even lower than those of the original polymer solution. In terms of our work, we were interested in the rheological aspect of HEC by studying the effect of temperature and concentration on the rheological properties of water-based solutions.