Interactions between amphiphilic polymers and cyclodextrins.
Date of Issue2007
School of Mechanical and Aerospace Engineering
The solution properties of various types of telechelic hydrophobically modified ethylene oxide urethane polymer (HEUR) in the presence of cyclodextrins were examined. Methylated (3 cyclodextrin (m-pCD) could effectively reduce the steady shear viscosity and the dynamic moduli of HEUR aqueous solutions. It was found that m- PCD interacts with HEUR in three progressive steps. At very low m-(3CD concentrations, m-pCD encapsulates the hydrophobes of looping HEUR chains, which destabilizes the transient network, while maintaining the number of mechanically active chains. However, the m-pCD/HEUR complex solutions become more sensitive to shear stress. At moderate m-pCD concentrations, m-pCD begins to deactivate the bridging chains resulting in a reduction in the number of mechanically active chains and this further weakens the transient network. Finally, when m-pCD is in excess, the network Methylated P-Cyclodextrin could effectively reduce the steady shear viscosity and dynamic moduli of HEUR aqueous solutions.