Preparation and charcterization of Konjac superabsorbent polymer

Abstract

A superabsorbent polymer was prepared by grafting sodium acrylate (SA) onto Konjac flour using potassium persulfate (KPS) and N, N′-methylene bis acrylamide (MBA) as an initiator and crosslinker, respectively. The effect of various preparation conditions on its water absorbency was investigated. When the Konjac Flour content was 3.0 g, the acrylic acid (AA) content was 30.0 g, the amount of initiator was 0.150 g, the neutralization degree of monomer was 85%, the reaction temperature was 60°C and the amount of crosslinker was 0.025 g, the polymer's absorbency was 750 times in pure water and 279 times in tap water at ambient temperature. It had also high water retention. The graft efficiency reached 67%. The analyses of FT-IR and SEM indicate that sodium acrylate is grafted on the polysaccharides of Konjac flour.

Keywords

Konjac / superabsorbent polymer / preparation / characterization

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