▎ 摘　　要

The thermostable chemically blended elastic poly-(acrylic acid-sodium-styrene-sulfonate-graphene oxide) super-absorbent hydrogel was synthesized by additive-free gamma-radiation induced polymerization followed by crosslinking method. It showed the best swelling ratio in water due to its porous nature. The composite material adsorbed 98 mg/g Cu(II) at room temperature from the aqueous solution of Cu(II) at pH 5 by the chemi-adsorption of Cu(II) ions at several energetically heterogeneous functional groups. The copper nanoparticles (CuNPs) of size 12 +/- 8 nm had been synthesized in situ by chemical reduction of the pre-adsorbed Cu(II) ions. The functional groups of composite hydrogel served as complexing agent and nano-reaction sites. Avoiding any pre-reduction induction time, the inexpensive CuNPs catalytically completely decolorized the aqueous solution of 4-nitrophenol (4-NP) within 60 s in the presence of NaBH4 at a promising calculated rate constant (9.0 x 10(-2)/s) ever reported in the literatures. It is in contrast to the commonly noticeable phenomenon for other CuNPs-based catalysis of 4-NP. The composite hydrogel matrix helped to retain the catalytic activity of CuNPs and simultaneously it helped in the osmotic inclusion of 4-NP into the reaction cites. This composite hydrogel synthesized through a chemically clean method could be utilized for efficient conversion of hazardous chemical 4-NP to industrially important chemical 4-aminophenol. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46200.