Novel dual-stimuli-responsive polymers derived from ethylpyrrolidine

This paper describes the synthesis and characterization of the new stimuli-responsive polymer poly(N-ethylpyrrolidine methacrylate), PEPyM. The polymer exhibits a phase separation transition temperature in water at 15 degrees C, being also sensitive to pH changes. The phase transition temperature can be modulated up to 80 degrees C by copolymerizing EPyM with different amounts of N,N'-dimethylacrylamide (DMA). EPyM was cross-linked with low amounts of bisacrylamide (B-Aam), and PEPyM gels were also sensitive to temperature and pH, showing a pulsatile behavior in response to both stimuli. The water sorption process (swelling kinetics) of the hydrogels at different temperature and pH was also studied in distilled water and in different buffer solutions.