Tuning the thermoresponsive properties of Hyperbranched Poly(ester amide)s based on diisopropanolamine and cyclic dicarboxylic anhydrides

Abstract

A range of water-soluble hyperbranched poly(ester amide)s has been synthesized with a view to studying their thermoresponsive behavior in water. Poly(ester amide)s with lower critical solution temperature (LCST) values around physiological temperatures are of interest for biological and medical applications, whereas poly(ester amide)s with high LCST values may be useful as kinetic hydrate inhibitors for high salinity produced fluids in the oil and gas industry. The LCST of these polymers was measured as the optical cloud point. The LCST can be tuned in various ways for these applications, for example, by varying the hydrophobicity of the groups on the cyclic anhydride monomer or by adjusting the hydrophilicity of the imine used to make the peripheral groups of the polymer.