Thermo-Responsive Allyl-Functionalized 2-(2-Methoxyethoxy)ethyl Methacrylate-Based Polymers as Versatile Precursors for Smart Polymer Conjugates and Conetworks

Several thermo-responsive polymers functionalized with allyl pendant groups were synthesized by copolymerizing 2-(2-methoxyethoxy)ethyl methacrylate (MEO(2)MA) and a low ratio of ally! methacrylate (AMA) via atom transfer radical polymerization (ATRP). The thermo-responsive behavior in aqueous solution of these P(MEO(2)MA-co-AMA) copolymers was analyzed, observing that the cloud point temperature (T-cp) decreased with the increment of the hydrophobic AMA units in the copolymer. More interestingly, these polymers bear ally! reactive groups, which can be used to form new thermo-responsive polymers. To demonstrate this synthetic versatility, on the one hand, these polymers were converted into fluorescent polymers by a thiol-ene click reaction between the allyl group and a thiol-functionalized BODIPY dye. On the other hand, they were also employed as cross-linkers for the UV initiated free radical polymerization of N-isopropylacrylamide (N-iPAAm) to form thermo-responsive conetworks structures, which show high swelling capacity and a sharp thermal phase transition in water solution.