Preparation of thermosensitive, calix[4]arene incorporated P(NIPAM‐co‐HBCalix) hydrogel as a reusable adsorbent of nickel(II) ions. Issue 11 (15th March 2013)

• Record Type: Journal Article
• Authors: Yan, Fanyong; Wang, Meng; Cao, Donglei; Guo, Shanshan; Chen, Li
• Is Part Of: Journal of polymer science. Volume 51:Issue 11(2013:Jun.)
• Page Start: 2401
• Page End: 2408
• Publication Date: 2013-03-15
• Subjects: 547
• DOI: 10.1002/pola.26625
• Languages: English
• ISSNs: 0887-624X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>A calix‐conjugated thermo‐responsive hydrogel containing 15% tetra(5‐hexenyloxy)‐p‐tert‐butylcalix[4]arene (HBCalix), P(NIPAM‐<italic>co</italic>‐HBCalix), was used to remove nickel(II) ions from water. Both thermo‐sensitive properties and the Ni<sup>2+</sup>‐adsorption capabilities of the prepared P(NIPAM‐<italic>co</italic>‐HBCalix) hydrogels are investigated. Introduction of the monomer HBCalix considerably enhanced the adsorption of Ni<sup>2+</sup> onto the hydrogel by chelation between hexenyloxy groups and metal ion. When HBCalix units capture Ni<sup>2+</sup> and forms HBCalix/Ni<sup>2+</sup> host–guest complexes, the lower critical solution temperature of the hydrogel shifts to a higher temperature due to both the repulsion between charged HBCali/Ni<sup>2+</sup> groups and the osmotic pressure within the hydrogel. Adsorption studies were carried out by varying contact time, counter ion and initial concentration of Ni<sup>2+</sup>. The evaluation of adsorption properties showed that the hydrogel exhibited better correlation with Langmuir isotherm model. P(NIPAM‐<italic>co</italic>‐HBCalix) could be used repeatedly with little loss in adsorption capacity by simply changing the environmental temperature. This kind of ion‐recognition hydrogel is promising as a novel adsorption material for adsorption and separation of Ni<sup>2+</sup> ions. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2401–2408</p> </abstract>