Solution structure and viscoelasticity of cellulose ethers in the presence of chaotropic nano-ions

Cellulose ethers, such as hydroxypropyl cellulose (HPC) are widely-used commcercial viscosifying agents due to their high molecular stiffness, in comparison to classical synthetic polymers like PS , and their tendency to self-aggregate in solution. In this research project we study the effects of chaotropic (water structure-breaking) and hydrophobic nanometric ions on the solution structure and rheology of HPC. We observed that the chaotropic nano-ion induced stronger effects on HPC rheology - a drastic viscosity increase towards gelation at millimolar concentrations - than the corresponding ionic surfactant (SDS)/polymer system. Interestingly, upon heating the viscosity of the nano-ion/HPC-complex was found to decrease drastically, which is uncommon for HPC that gels upon heating. With this proposal we aim to correlate the temperature induced viscosity trend with the solution structure.