Patent GB-692957-A (GB)
Title: Improvements relating to polymers and their preparation
IPC: C08G61/04
Filed: 1951-01-31
Abstract: Orientable, essentially hydrocarbon, polymers are prepared by reacting carbon monoxide with hydrogen under pressure in the presence of a molybdite of a metal whose ions are soluble in aqueous ammonia in amount greater than that stoichiometrically required to precipitate the ion, the molybdite being of an acid having one of the formul  H2MoO2 and H2MoO3.  Suitable salts are copper molybdite (CuMoO3), nickel molybdite (NiMoO2) and cobalt molybdites (CoMoO2 and CoMoO3).  These can contain promoters or modifiers such as cadmium, barium, chromium, thorium, cobalt, zinc and copper.  In practice, a pressure vessel is charged with a diluent and the molybdite catalyst, swept with oxygen-free nitrogen, cooled to 0 DEG C. and evacuated. It is then pressured with a predetermined carbon monoxide/hydrogen mixture and heated to between 125 DEG  and 300 DEG  C., with repressuring of the mixture.  Pressures of at least 200 atmospheres, preferably 500-5000, are maintained.  On completion and cooling, the contents are filtered and the solid polymer is separated from the catalyst by extraction.  Suitable reaction media are water, and hydrocarbons and alcohols, those specified being tetra- and deca-hydronaphthalenes, xylene, cyclohexane and toluene.  In aqueous media, the presence of an acid, e.g. sulphuric, is advantageous from the stand-point of molecular weight; and in organic media, acids or alkyl acid phosphates are desirable.  The catalyst may be pretreated with these acids instead of adding them to the medium.  The process may also be carried out in the presence of basic materials.  The catalyst may be in the form of pellets or finely-divided powder and may be extended on inert supports such as charcoal, alumina or silica.  The polymers, which have inherent viscosities of at least 0.74 and molecular weights of at least 12,000, are convertible into orientable fibres and films.  U.S.A. Specifications 2,351,345, 2,352,328 and 2,572,300 are referred to.ALSO:Orientable, essentially hydrocarbon, polymers are prepared by reacting carbon monoxide with hydrogen under pressure in the presence of a molybdite of a metal whose ions are soluble in aqueous ammonia in amount greater than that stoichiometrically required to precipitate the ion, the molybdite being of an acid having one of the formul  H2MoO2 and H2MoO3. Suitable salts are copper molybdite (CuMoO3), nickel molybdite (NiMoO2) and cobalt molybdites (CoMoO2 and CoMoO3).  These can contain promoters or modifiers such as cadmium, barium, chromium, thorium, cobalt, zinc and copper.  In practice, a pressure vessel is charged with a diluent and the molybdite catalyst, swept with oxygen-free nitrogen, cooled to 0 DEG  C. and evacuated.  It is then pressured with a predetermined carbon monoxide/hydrogen mixture and heated to between 125 DEG  and 300 DEG  C., with repressuring of the mixture.  Pressures of at least 200 atmospheres, preferably 500-5000, are maintained.  On completion and cooling, the contents are filtered and the solid polymer is separated from the catalyst by extraction. Suitable reaction media are water and hydrocarbons and alcohols, those specified being tetra- and deca-hydronaphthalenes, xylene, cyclohexan and toluene.  In aqueous media, the presence of an acid, e.g. sulphuric, is advantageous from the standpoint of molecular weight; and in organic media, acids or alkyl acid phosphates are desirable.  The catalyst may be pretreated with these acids instead of adding them to the medium.  The process may also be carried out in the presence of basic materials.  The catalyst may be in the form of pellets or finely-divided powder and may be extended on inert supports such as charcoal, alumina or silica.  The polymers, which have inherent viscosities of at least 0.74 and molecular weights of at least 12,000, are convertible into orientable films and fibres. U.S.A. Specifications 2,351,345, 2,352,328 and 2,572,300 are referred to.ALSO:Molybdites of metals whose ions are soluble in excess aqueous ammonia are used as catalysts in the preparation of hydrocarbon polymers from carbon monoxide and hydrogen (see Group IV(a)). Copper, nickel and cobalt molybdites are specified, corresponding to the formal  CuMoO3, NiMoO2, CoMoO2 and CoMoO3.  These may be modified by cadmium, barium, chromium, thorium, cobalt, zinc and copper.  The preparation of nickel molybdite is described whereby ammonium paramolybdate in aqueous solution is neutralized by the addition of ammonia, nickel nitrate is added forming a green precipitate in a slurry, the pH is adjusted to 7 and the precipitate calcined.  The product is then reduced in hydrogen at temperatures increasing to 550 DEG  C giving a pyrophoric material of the formula NiMoO2/O2MoO3, which glows in air.  A cadmium modified nickel molybdite is prepared by adding a neutralized solution of ammonium paramolybdate to a solution of nickel nitrate hexahydrate and cadmium nitrate tetrahydrate.  The calcined precipitate is reduced in a nitrogen/hydrogen mixture when cadmium metal volatilizes out and the product is pyrophoric and glows in air. U.S.A. Specification 2,572,300 is referred to.