Study on superabsorbent composite. V. Synthesis, swelling behaviors and application of poly(acrylic acid‐co‐acrylamide)/sodium humate/attapulgite superabsorbent composite

Abstract A novel multifunctional superabsorbent composite from acrylic acid (AA), acrylamide (AM), sodium humate (SH) and attapulgite (APT), PAA‐AM/SH/APT, was synthesized by aqueous solution polymerization, using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and ammonium persulfate (APS) as an initiator. In this paper, not only the effects of the ratio of AA to AM, SH and APT content on the saturated water absorbency, but also various swelling behaviors of the composite were systematically investigated. The results show that comprehensive performances of the superabsorbent are improved by introducing functional components into a poly(acrylic acid‐acrylamide) (PAA‐AM) network. Functionality of the composite in practice was also investigated by studying the release of SH and by growing Elymus dahuricus Turcz (a kind of grass) plants in soil with and without using the superabsorbent composite. The roots and stems of Elymus dahuricus Turcz were found to be sturdier compared with the plants grown without the superabsorbent composite. Copyright © 2005 John Wiley & Sons, Ltd.