Metal-Ion Complexation Behavior of Resins Prepared by a Novel Template Polymerization Technique

Abstract

A Cu2+-ion selective resin (resin A) was synthesized by a novel template polymerization technique, using oleic acid as a host monomer, divinylbenzene as a matrix-forming monomer and Cu2+ ion as a target molecule. The metal (Cu2+ and Cat) ion complexation equilibria of resin A together with a reference resin (resin B) studied potentiometrically indicate: l) rapid and reversible complexation reactions, and 2) a highly selective binding of resin A to Cu2+ ions. These properties show that Cu2+-ion selective cavities were formed at the surface of resin A. The concept of molecular recognition has drawn special attention in regarding recent separation analytical chemistry. In order to obtain fine guest-recognizing molecules, a large number of studies have been reported concerning the design and synthesis of supramolecules;1 however, the required multi-step preparation procedures are sometimes tedious and the yields are not always high. Another possible approach for guest-recognizing molecules is a template polymerization technique, the idea of which was proposed by Wulff and Sarhan 20 years ago.2The template polymerization technique is well-known as a method for synthesizing host polymers, and is called "molecular imprinting".3 In this technique a target molecule is incorporated into polymerizable compounds with functional groups (host monomers). Then, the complex is polymerized with a matrix-forming monomer to give a resin (Fig. 1). Upon washing out the target molecules cavities remain in the polymer matrix. The cavities memorize the spacial structures and shapes of the target molecule, so that the polymers selectively bind to the molecule. By template polymerization, Wulff et al. have succeeded in separating racemates on polymers having chiral cavities.2 Nishide et al. have synthesized highly selective metal-ion exchange resins by templating metal ion.4In this work we designed template polymerization at an oil-water interface (Fig. 2). Both a target molecule (water-soluble) and a host monomer (amphiphilic) approach at the vicinity of the interface and arrange orderly. The order of the molecular assemblies is controlled by the complexation of the target molecule with the host monomer. The oil phase comprising a matrixforming monomer is polymerized to give a resin, so that target-selective cavities are formed at the resin surface. This enables a rapid and reversible complexation of the target molecule by the host polymers.In this paper we describe the preparation of metal-ion selective resins using surface template polymerization. Resins have been synthesized using oleic acid as an amphiphilic host monomer, divinylbenzene as an oil (resin-forming monomer), and metal ion (Cu2+) as the target molecule. The characteristics of metal-ion (Cu2+ and Cat) complexation equilibria of the resins have also been examined.

Polímeros impressos com íons: fundamentos, estratégias de preparo e aplicações em química analítica

“…23 Entre as vantagens da técnica incluem-se a cinética de ligação rápida e a facilidade em lidar com impressões de íons hidrofílicos. Assim, uma série de trabalhos têm sido publicados usando esta técnica, por exemplo, para os íons Co 2+ , Ni 2+ e Cu 2+ com microesferas impressas preparadas por polimerização em emulsão por sementes, que são obtidas utilizando estireno, divinilbenzeno, burilacilato e ácido metacrílico em água.…”

Condensed-Phosphate Imprinted Resins Prepared by a Surface Template Polymerization Method

“…Template Polymerization Method † Isamu FUJIWARA,* Mizuo MAEDA,** and Makoto TAKAGI*** already reported on the preparation of a templated resin by using this method for catching metal ions using oleic acid 8 and phosphoric acid 9,10 as functional surfactants. We also prepared the templated resin for ferrocyanide ion 11 using oleylamine as a surfactant monomer.…”

Synthesis of molecular imprinted polymer networks

“…Therefore processes that give access to the large surface area of polymer colloids and yield materials that are useful in chromatography are attractive. Takagi et al [22][23][24][25] originally reported a metal imprinted polymer colloid. The method involves the use of a host surfactant that is a polymerizable surfactant with …”