Phenol-formaldehyde macrocycles in polymer systems.
Part. I. Preparation methods involving chain polyreactions and immobilization on polymer matrix
Polimery 2000, No 4, 225
SummaryA review with 39 references covering synthesis, properties and uses (especially for complexation of ions and neutral molecules) of polymers containing in-built phenol-formaldehyde macrocycles (calixarenes) with particular reference to the methods of bonding them to polymer chains. New methods are described to prepare multicalixarene oligomers endowed with dendritic and supramolecular structures. There are two fundamental methods to synthesize polymer systems including covalently linked calixarene units, viz., (i) making a calixarene to react with a suitably functionalized polymer and (ii) preparation of a calixarene monomer and its subsequent polymerization or copolycondensation with commercial monomers. Method (ii) allows better-defined products to be prepared, because it eliminates the risk of incomplete reaction of the functional groups of the polymer that in method (i) was used as a matrix. Calixarene monomers have been incorporated into polymer backbones by using functional groups at the narrow and at the wide rim. A drawback to the methods is that, when linked to the polymer chain, calixarene ionophores can result in distorted binding sites because the interactions of the polymer backbone with macrocycle's receptor groups can result in reduced selectivity of complexation by the ionophor. In some cases conjugation of a calixarene with the polymer backbone can result in enhanced ionophore's properties, e.g., on account of cumulated bond formation in the polymer chain.