Synthesis and properties of sodium alginate/poly(acrylic acid) double-network superabsorbent

AbstractA tough double-network (DN) superabsorbent was synthesized by a two-step method using N,N-methylenebisacrylamide as a covalent cross-linker for one monomer [acrylic acid (AA)], Ca2+ (CaCl2) as an ionic cross-linker for the other monomer (sodium alginate [SA]) and ammonium peroxodisulfate as the redox initiator. The optimized experimental conditions for the absorbency in deionized water were determined according to orthogonal experiments. Unlike conventional chemical cross-linked single-network superabsorbents, SA/poly(acrylic acid) (PAA) DN superabsorbents exhibit superb mechanical properties. Compared with the tensile strength of PAA-only superabsorbents, that of SA/PAA DN superabsorbents showed an approximately 371.9% increase with increasing amount of 6 wt.% SA. We also investigated the capacity of SA/PAA DN superabsorbents to remove heavy metal ions. It was found that the addition of SA can truly increase the metal ion removal capacity of the PAA superabsorbents and that the affinity order was Pb2+>Zn2+.

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Nanocomposite hydrogel based on sodium alginate, poly (acrylic acid), and tetraamminecopper (II) sulfate as an efficient dye adsorbent

Carbohydrate Polymers ◽

10.1016/j.carbpol.2021.118182 ◽

2021 ◽

pp. 118182

Author(s):

Tannaz Mozaffari ◽

Abolfazl Keshtkar Vanashi ◽

Hossein Ghasemzadeh

Keyword(s):

Acrylic Acid ◽

Sodium Alginate ◽

Nanocomposite Hydrogel ◽

Poly Acrylic Acid

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Determination of the complexation properties of a crosslinked poly(acrylic acid) gel with copper(II), nickel(II), and lead(II) in dilute aqueous solution

Canadian Journal of Chemistry ◽

10.1139/v01-059 ◽

2001 ◽

Vol 79 (4) ◽

pp. 370-376 ◽

Cited By ~ 5

Author(s):

Catherine Morlay ◽

Yolande Mouginot ◽

Monique Cromer ◽

Olivier Vittori

Keyword(s):

Aqueous Solution ◽

Ionic Strength ◽

Acrylic Acid ◽

Metal Ion ◽

Conditional Stability ◽

Binding Properties ◽

Complex Species ◽

Complexing Capacity ◽

Dilute Aqueous Solution ◽

Poly Acrylic Acid

The possible removal of copper(II), nickel(II), or lead(II) by an insoluble crosslinked poly(acrylic acid) was investigated in dilute aqueous solution. The binding properties of the polymer were examined at pH = 6.0 or 4.0 with an ionic strength of the medium µ = 0.1 or 1.0 M (NaNO3) using differential pulse polarography as an investigation means. The highest complexing capacity of the polyacid was obtained with lead(II) at pH = 6.0 with µ = 0.1 M, 4.8 mmol Pb(II)/g polymer. The conditional stability constants of the complex species formed were determined using the method proposed by Ruzic assuming that only the 1:1 complex species was formed; for lead(II) at pH = 6.0 and µ = 0.1 M, log K' = 5.3 ± 0.2. It appeared that the binding properties of the polymer increased, depending on the metal ion, in the following order: Ni(II) < Cu(II) < Pb(II). The complexing capacity and log K' values decreased with the pH or with an increase of the ionic strength. These results were in agreement with the conclusions of our previous studies of the hydrosoluble linear analogues. Finally, with the insoluble polymer, the log K' values were comparable to those previously obtained with the linear analogue whereas the complexing capacity values expressed in mmol g-1 were slightly lower.Key words: insoluble crosslinked poly(acrylic acid), copper(II), nickel(II), and lead(II) complexation.

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