Abstract: The subject composite materials comprise an association of an organic elastic matrix with a network of non-oxidized quasi spherical particles, of submicronic dimension and of a diameter ranging between 0.1 .mu.m and 10 .mu.m, distributed uniformly in the matrix.The materials are intended to coat pieces subjected to the phenomena of wear, erosion, cavitation and abrasion notably in a corrosive medium.According to a method of manufacture of these composite materials, the nonoxidized submicronic particles are, immediately before their introduction in the organic matrix, plunged into an organic macromolecular dispersant chosen of such type that the macromolecular chains of the dispersant are fixed on the surface of the particles by noncovalent bonds.

Abstract: The subject composite materials comprise an association of an organic elastic matrix with a network of non-oxidized quasi spherical particles, of submicronic dimension and of a diameter ranging between 0.1 .mu.m and 10 .mu.m distributed uniformly in the matrix.The materials are intended to coat pieces subjected to the phenomena of wear, erosion, cavitation and abrasion notably in a corrosive medium.According to a method of manufacture of these composite materials, the nonoxidized submicronic particles are, immediately before their introduction in the organic matrix, plunged into an organic macromolecular dispersant chosen of such type that the macromolecular chains of the dispersant are fixed on the surface of the particles by noncovalent bonds.

Abstract: A cathode coating comprises a catalyst for hydrogen evolution finely dispersed in a matrix consisting of an insoluble, semiconducting polymer which is formed in situ on an electrode support body. A bipolar electrode is provided with such a cathode coating on a support body consisting of a valve metal such as titanium.The cathode coating is formed by applying to the electrode support body a coating solution which contains an inorganic precursor compound for the hydrogen evolution catalyst and an organic precursor compound for forming the polymer matrix, drying and then thermally converting these precursors to a cathode coating adhering to the electrode support body.

Abstract: A catalytic electrode has an electrically conductive substrate such as titanium or lead and is provided with a coating comprising a platinum-group metal catalyst finely dispersed in a matrix consisting of a semi-conducting polymer formed in situ on the substrate. The catalyst may be a platinum-group metal oxide such as iridium oxide formed in situ together with the semi-conducting polymer by a controlled heat treatment.The semi-conducting polymer is preferably formed from polyacrylonitrile, polybenzimidazo-pyrrolone or an adamantane based polybenzoxazole.

Abstract: Catalytic particles with an inert, corrosion resistant support material are provided with a catalyst finely dispersed in a matrix of an insoluble electrically conducting polymer formed in situ on each particle of inert support material.The inert support particles are catalytically activated by:(a) wetting them with a solution containing an inorganic precursor compound for the catalyst and an organic precursor compound for the insoluble polymer matrix,(b) drying the particles, and(c) heat treating them to convert the precursors to the catalyst dispersed in the polymer matrix.An electrode, e.g. an oxygen-evolving anode, is produced by either fixing the catalytic particles to an electrode base, e.g. lead, or by consolidating the catalytic particles into a porous electrode body.

Abstract: Into a liquid medium consisting of a solvent having dissolved therein a substance (solute) which is to be separated from the liquid medium, there is introduced a macromolecular substance capable of selectively fixing the molecules of the substance to be separated. The macromolecular substance forms, before and after fixing the substance to be separated, a homogeneous liquid phase in admixture with the liquid medium. After allowing the substance to be fixed by the molecules of the macromolecular substance, the liquid medium thus obtained is passed through a semipermeable ultrafiltration membrane which retains the associations of molecules formed between the macromolecular substance and the substance to be separated but allows the molecules of the solvent to pass through.