(US5120407-A)      Preparing a five-membered heterocyclic electroconductive polymeric film of formula (II) is new. (II) has an electrical conductivity of 100 S/cm or more. The process comprises electrically polymerising five-membered heterocyclic monomers of formula (I) in the presence of tetrabutyl ammonium alkyl sulphate as an electrolyte and an organic solvent. No water is used during processing. M = N or S; provided H is deleted when M = S; R = H or 4-22C aliphatic alkyl gp., provided that R = H when M = N; R = H or 4-22C aliphatic alkyl gp. when M = S; A = an anion.    USE/ADVANTAGE -   The polymer film has good electrochemical reversibility, electric conductivity and mechanical properties.    (DE4104493-C2)      5-Membered, heterocyclic, electrically conducting polymers (1) having a conductivity at least 100 S/cm are prepared by electrochemical polymerisation of a 5-membered heterocyclic monomer (2) in presence of tetrabutyl dodecyl sulphate as electrolyte in an organic solvent, pref. acetonitrile or propene carbonate. In the formulae X is N or S and when X is S there is no H or X; R is H or 4-22C alkyl; A is an anion formed in the polymerisation cell by electrolytic dissociation.    ADVANTAGE -   The polymers have outstanding electrical reversability, electrical conductivity and excellent mechanical properties.    (JP94060235-B2)      Prodn. of electrically-conducting 5-membered heterocyclic polymers of formula (I) with conductivity 100 S/cm or above, comprises electrochemical polymerisation of 5-membered heterocyclic monomers of formula (II) in the presence of tetrabutylammonium alkyl sulphate (III) as electrolyte and an organic solvent; M = N, or S (if M = S there is no H or M); R = H, (if M = N) or H or 4-22C alkyl (if M = S); A = anion produced by electrolytic dissociation in the polymerisation cell.    Pref. (II) is pyrrole, thiophene or a thiophene deriv. with 4-22C alkyl in the 3-position, and (I) is the corresp. polypyrrole or opt. substd. polythiophene; solvent is MeCN or propylene carbonate, and (III) is Bu4N dodecylsulphate (IIIA).    USE/ADVANTAGE -   The process enables the prodn. of a polymer film (I) with excellent electrochemical reversibility, high electrical conductivity and excellent mechanical properties (compared with (I) contg. small anions A as dopant). The polymers are useful e.g. in semiconductor elements and solar cells etc.