Polymeric membrane selective to calcium (II) ions

摘要

Polymeric membrane selective to calcium (II) ions. The invention relates to a polymeric membrane selective to calcium (II) ions, formed by a solid film of plastic material, advantageously of poly(vinyl chloride), which contains an active neutral carrier in a plasticizer of the used plastic material. The active carrier is a complex of macrocyclic polyetherdiamides of the general formula ##STR1## where R.sub.1, R.sub.2, R.sub.3, R.sub.4 are H or alkyl containing 1 to 4 carbon atoms, advantageously methyl, R.sub.5 and R.sub. 6 mean alkyl or arylalkyl with 6 to 10 carbon atoms, advantageously benzyl, with the calcium (II) ions and a lipophilic organic anion, advantageously with tetraphenylborate or tetra(p-chlorophenyl)borate anion.