TECHNOLOGY FOCUS - POLYMERS - Preferred materials: (A) has a polyethylene oxide group or a cyclic carbonate group or a cyclic ether group substituted on Si, and has at least two SiH groups 10-95% (especially 40-90%) of silicon atoms in (A) have a substituent of polyethylene oxide group with 1-12 polymerization degree of oxyethylene units. (C) is at least one from platinum compounds, ruthenium compounds and rhodium compounds. (D) comprises a cation from metal cations, ammonium ions, amidenium ions and guanidium ions, and an anion from chlorine ions, bromine ions, iodine ions, perchlorate ions, thiocyanate ions, tetrafluoroborate ions, nitrate ions, AsF6-, PF6-, stearylsulfonate ions, octylsulfonate ions, dodecylbenzenesulfonate ions, naphthalene sulfonate ions, dodecylnaphthalene sulfonate ions, R1SO3-, (R1SO2)(R2SO2)N- and (R1SO2)(R2SO2)(R3SO2)C-R1, R2, R3 = electron attracting group, preferably 1-6C perfluoroalkyl or perfluoroaryl.The metal cation is a Periodic Table series 1 or 2 metal cation (preferably lithium cation), or a transition metal cation, or it is a Mn, Fe, Co, Ni, Cu, Zn or Ag cation. (D) is LiClO4, LiPF6, LiBF4, LiCF3SO3, LiN(CF3SO2)2 or Li(C2F5SO2)2.Preferred composition: (D) is 0.10-5.0 mmoles per g composition. EXAMPLE - 4 g polymethylhydrodiene siloxane, 10 g toluene and 1.2 x (10 raised to power -3) mmole Pt vinylsiloxane were reacted at 80 degreesC with stirring, 24 g polyethylene oxide (400 average mol. wt.) having allyl terminal groups were added dropwise, reacted for 3 h, then the toluene removed, to give a polysiloxane with 74% introduced polyethylene oxide (proportion of Si atoms with polyethylene oxide substituent groups with respect to total Si). To 3.0 g this were added 73 mg bisphenol A diallylether, 7.2 x (10 raised to power -4) mmole Pt vinylsiloxane and 108 mg LiClO4 dissolved in 1 ml tetrahydrofuran, mixed, and heated at 80 degreesC for 4 h in a press, to give a colorless transparent thin film. The film had 1.5 x (10 raised to power -4) S/cm ionic conductivity (Pt electrode, 0.5 V, 42 Hz - 5 MHz, 25 degreesC).