ELECTROCHEMICAL OXIDATION AND POLYMERIZATION OF IV-GROUP HETEROCYCLIC-COMPOUNDS - N-METHYL-10,10-DIMETHYLPHENAZASILINE AND N-METHYL-10,10-DIMETHYLPHENAZAGERMINE - 10,10-DIMETHYLPHENOTHIASILINE 10,10-DIMETHYLPHENOTHIAGERMINE AND 10,10-DIMETHYLPHENOTHIASTANNINE