Cellulose ethers in aqueous solution

The behaviour of polymer molecules in solution depends to a large extent on the polymer concentration, c. Most applications where CDs are used are in the semidilute region. In dmg delivery systems for pharmaceutical applications the polymer is likely to be in the highly concentrated regime where the polymers form a gel. 

The strength of the hydrophobic interactions between polymer chains is influenced by the length of the hydrophobic groups and the molar substitution of hydrophobic groups (MShydrophobe )  

The influence of MShydrophobe on the solution viscosity can be divided into three different regions. At low MShydrophobe values there is a positive correlation between MShydrophobe and viscosity. This can be explained by an increased number of interconnection points holding the polymer network together. Depending on the structure of the 

The rheology profiles of cellulose ethers differ depending on MW and type of substituents. When comparing two cellulose ethers with the same substitution pattern but with different MWs the shear rate dependence of the viscosity is much more pronounced 

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