Ultrasonic Synthesis and Properties of Sodium Lignosulfonate-grafted Poly(Acrylic Acid-co-Vinyl Alcohol) Composite Superabsorbent Polymer

In this paper, a green and high-efficiency method (ultrasound synthesis) has been applied in the preparation of a sodium lignosulfonate-grafted poly(acrylic acid-co-vinyl alcohol) superabsorbent polymer (SL-P(AA-co-VA)). By Fourier-transform infrared spectroscopy, scanning electron microscopy, and thermogravimetry-differential scanning calorimetry, the successful preparation was confirmed. An L-16(4)(5) orthogonal experiment was carried out to optimize synthetic conditions for SL-P(AA-co-VA). Under the optimized synthetic conditions, maximum water absorbency (949 g g(-1)) and physiological saline absorbency (62 g g(-1)) were achieved. Adjusting pH reduces the water absorbency of SL-P(AA-co-VA), as does the presence of metal ions. However, a rise in temperature does not have a significant influence on it. In general, both the water absorbency and physiological saline absorbency of SL-P(AA-co-VA) were significantly improved versus P(AA-co-VA) superabsorbent.