Clustering and Dissolution of Triazole Branched Poly(ethyl methylacrylate)

Abstract

The solution properties of the multiresponsive polymer P1 (poly(2-((3-(1-(2-(dimethylamino)ethyl)-1H-1,2,3-triazol-4-yl)propanoyl)oxy)ethyl methacrylate) are studied by small angle neutron scattering (SANS) and dynamic light scattering (DLS). The P1 solution exhibits a phase transition above certain temperatures and cloud points following dissolution through the incubation at room temperature. SANS and DLS studies show that P1 forms clusters via hydrophobic interactions, which are weakened by continued incubation. The temperature dependent cluster formation is explained by hydrophobic adsorption and shrinking behavior as a function of hydrodynamic radius, correlation lengths, and Porod exponents. The weak clustering and solution property are discussed on the basis of Flory theory. Taken together, the results here indicate that time-dependent dissolution of P1 leads to a weakly hydrophobic structure.