Synthesis of the polymerizable room temperature ionic liquid AMPS – TEA and superabsorbency for organic liquids of its copolymeric gels with acrylamide

Abstract

A polymerizable room temperature ionic liquid (RTIL), 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) – triethylamine (TEA), was synthesized by neutralization of AMPS with TEA in acetone followed by evaporation of the solvent under a reduced pressure at room temperature. The RTIL was characterized with fourier transform infrared spectroscopy, differential scanning calorimetry (DSC), and ¹H NMR. Co-polymeric gels of the RTIL with acrylamide (AAm) were prepared by aqueous solution polymerization using N,N′-methylenebisacrylamide as a crosslinker, and ammonium persulfate as an initiator. Superabsorbency of the gels in aqueous and a series of organic liquids was investigated gravimetrically. DSC data showed that the glass transition temperature of AMPS – TEA was −59.4 °C. Poly(AMPS – TEA-co-AAm) gels exhibited superabsorbency in both water and a series of organic solvents. The mechanism for swelling in aqueous and organic media of the gels was critically discussed.

Keywords:

• 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS)
• triethylamine (TEA)
• room temperature ionic liquid (RTIL)
• acrylamide
• superabsorbency