PREPARATION OF ULTRAFINE METAL PARTICLES IN PROCESSES OF PULSE MECHANICAL ACTION

Ultrafine metal particles (UFMP) (iron and cobalt) have been obtained in solid-state redox reactions of cyclopentadienyl-pi-(3)-1,2-dicarbol lyliron or cyclopentadienyl-pi-(3)-1,2-dicarbollylcobalt with elementa l sulfur ((C5H5Fe3+(C2B9H11)-S, (C5H5Co5+(C2B9H11)-S) These reactions are realized by the action of elastic wave (EW) pulses on powder compo sitions of these substances. Study of the UFMP obtained by the ferroma gnetic resonance (FMR) method has shown that the sizes of n . Co-0 UFP lie in the range from 1 to 13 nm. UFP of cobalt and iron are also for med under the action of EW on samples containing (C5H5Fe3+(C2B9H11)-S or (C5H5Co3+(C2B9H11)-S within the film of tetrafluoroethylene and per fluoro-4-methyl-3,6-dioxaoct-7-ene-1-sulfonyl fluoride copolymer (CP). It is shown by the FMR method that FMR lines broaden on going from po wder systems to systems containing CP films. It is supposed that n . C o-0 and n . Fe-0 particles interact with polymeric matrices in the cou rse of formation and stabilization of UFMP in the matrices.