Synthesis and Hydration Properties of the Superabsorbent “Solid water”

Abstract

Global warming has posed a number of challenges for agriculture. The key problem is water retention in soil. Existing irrigation methods are costly and ineffective. To solve this problem, a synthesis of a rare-cross-linked hydrophilic polymer material with the properties of a pectin-based superabsorbent was conducted. The paper considers the structure and moisture absorption of the polymer material “Solid water”. The hydration properties of the superabsorbent in its original state and after contact with pectins were determined using IR spectroscopy. Our research showed that the water-adsorbing ability is ensured by the presence of short-sized acrylamide residues, fragments with residues of carboxyl groups and polysaccharide units in the structure. The superabsorbent with pectin as a biodegradable component is able to retain a portion of water of hydration even during prolonged drying. The effect of the pH of the medium on the water absorption capacity and swelling of the superabsorbent “Solid water” was shown. This superabsorbent can be used in different types of soils, as confi rmed by the studies conducted in distilled water, as well as in alkaline and acidic media. The polymer is characterised by the highest swelling values in an alkaline medium due to the electrostatic repulsion of dissociated carboxyl groups, formed as a result of the hydrolysis of acrylamide. This makes it suitable for use in leached soils, such as leached black soil (Chernozem) in the Voronezh region. IR spectroscopy showed the presence of the superabsorbent’s functional groups that form supramolecular structures including bound water molecules with no additional coordinate covalent bonds present. Thus, the reactions can be characterised as processes with the elements of system self-organisation.

Keywords

• superabsorbent
• hydration properties
• water absorption
• pectin
• ir spectra.