Patent GB-600145-A (GB)
Title: Improvements in or relating to the treatment of copolymers
IPC: C08F10/00
Filed: 1945-09-28
Abstract: A copolymer of tetrafluoroethylene and a mono - olefin containing 2-4 C atoms is thermally cracked to obtain an unsaturated fluorine-containing oil or grease used in drying oils and lubricants or, after condensing with aromatic or halogenated compounds, as a blending agent for fuels and lubricants.ALSO:A copolymer of tetrafluoroethylene and a mono-olefin containing 2-4 carbon atoms is thermally cracked to convert it to an unsaturated fluorine-containing oil or grease.  The copolymer contains 1-80, especially 10-60 mol per cent of tetrafluoroethylene, and may be prepared by heating this with ethylene, isobutylene, propylene or butene or mixtures thereof, e.g. ethylene and isobutylene, at 40-150 DEG  C. under pressure in the presence of water and oxygen or a peroxy catalyst.  Cracking is effected at 400-700 DEG  C. at or below or above atmospheric pressure.  Copolymers of high mono-olefin content give more unsaturated products.  Catalysts for the cracking are nickel, cobalt, platinum, iron, alumina, silica, chromia, thoria, aluminium chloride and fluoride, and zinc fluoride.  A carrier such as carbon dioxide, nitrogen, hydrogen or methane may be used to agitate the mixture during the cracking and remove the product. The products are employed as lubricants and may be blended with oils or they may be condensed with aromatic compounds and halogenated compounds to give blending agents for fuels and lubricants.  They may also be used in waxes, polishes, coatings, and drying oils.  In examples: (1) a tetrafluoroethylene-isobutylene copolymer, 49 mol per cent of the former, is heated at 425-460 DEG  C. and 1 mm. in a stream of nitrogen giving an unsaturated grease as distillate; (2) a tetrafluoroethylene-ethylene copolymer, 16.3 mol. per cent of the former, is heated at 430-450 DEG  C. and 5 mm. giving a hard waxy distillate.ALSO:A copolymer of tetrafluoroethylene and a mono olefin containing 2-4 carbon atoms is thermally cracked to convert it to an unsaturated fluorine-containing oil or grease.  The copolymer contains 1-80, especially 10-60 mol. per cent of tetrafluoroethylene, and may be prepared by heating this with ethylene, isobutylene, propylene or butene or mixtures thereof, e.g. ethylene and isobutylene, at 40-150 DEG  C. under pressure in the presence of water and oxygen or a peroxy catalyst.  Cracking is effected at 400-700 DEG  C. at or below or above atmospheric pressure. Copolymers of high mono-olefin content give more unsaturated products.  Catalysts for the cracking are nickel, cobalt, platinum, iron, alumina, silica, chromia, thoria, aluminium chloride and fluoride and zinc fluoride.  A carrier such as carbon dioxide, nitrogen, hydrogen or methane may be used to agitate the mixture during the cracking and remove the product. The products are employed as lubricants and may be blended with oils or they may be condensed with aromatic compounds and halogenated compounds to give blending agents for fuels and lubricants.  They may also be used as waxes, polishes, coatings and drying oils.  In examples: (1) a tetrafluoroethylene-isobutylene copolymer, 49 mol. per cent of the former, is heated at 425-460 DEG  C. and 1 mm. in a stream of nitrogen giving an unsaturated grease as distillate; (2) a tetrafluoroethylene-ethylene copolymer, 16.3 mol. per cent of the former, is heated at 430-450 DEG  C. and 5 mm. giving a hard waxy distillate.