Synthesis and Analysis of Swelling and Controlled Release Behaviour of Anionic sIPN Acrylamide based Hydrogels

In modern agriculture, polymeric hydrogels are known as a component able to hold an amount of water due to their 3-dimensional network structure and their tendency to absorb water in humid environments. In addition, these hydrogels are able to controllably release the fertilisers and pesticides loaded in them. Therefore, they deliver these materials to the plants' roots and help them with growing. These hydrogels also reduce the pollution of underground water sources by preventing the active components from leaching. In this study, sIPN acrylamide based hydrogels are synthesised by using acrylamide free radical, potassium acrylate, and linear polyvinyl alcohol. Ammonium nitrate is loaded in the hydrogel as the fertiliser. The effect of various amounts of monomers and linear polymer, measured in molar ratio, on the swelling rate, equilibrium swelling, and release of ammonium nitrate is studied.

Authors:

• Atefeh Hekmat
• Abolfazl Barati
• Ebrahim Vasheghani Frahani
• Ali Afraz

Keywords:

• Hydrogel
• controlled release
• ammonium nitrate fertiliser
• sIPN.

References:

[1] A. K. Bajpai, and A. Giri, Swelling dynamics of a macromolecular
hydrophilic network and evaluation of its potential for controlled release
of agrochemicals, Reactive & Functional Polymers 53 (2002) 125.
[2] T. Caykara, S. Kiper, and G. Demirel, Thermosensetive poly(Nisopropyleacrylamide-
co-acrylamide) hydrogels: Synthesis, swelling and
interaction with ionic surfactants, 42 (2006) 348.
[3] T. Caykara and A. lkay, Synthesis and network structure of ionic
poly(N,N-dimethylacrylamide-co-acrylamide) hydrogels: Comparation
of swelling degree with theory, 42 (2006) 1473.
[4] K. Kabiri, and M.J. Zohuriaan-Mehr, Superabsorbent Hydrogel
Composites, Polym. Adv. Technol. 14(2003) 438.
[5] D. Liu, M. Sheu, C. Chen, Y. Yang, and H. Ho, Release characteristic of
lidocaine from local implant of polyanionic and poly cationic hydrogels,
Journal of Controlled Release 118 (2007) 333.
[6] A. S. Hoffman, Intelligent polymers in medicine and biotechnology,
Macromol. Symp. 98 (1995) 645.
[7] Z. Li, Use of surfactant-modified zeolite as fertilizer carries to control
nitrate release, Microprous and Meseporous Materials 61 (2003) 181-
188
[8] A.K. Bajpai, Anjali Giri, Swelling dynamics of a macromolecular
hydrophilic network and evaluation of its potential for controlled
release of agrochemicals, Reactive & Functional Polymers 53 (2002)
125-141
[9] A. Hekmat, A. B. Barati, M. Zendehdel, H. R. Norouzi, A. Afraz,
Synthesis and Analysis of Swelling and Controlled Release Behaviour of
Anionic sIPN Acrylamide Based Hydrogels, 12th National Chemical
Engineering Congress, Tbriz, Iran, 2008