Patent GB-799823-A (GB)
Title: Production of high molecular weight polyethylenes
IPC: C08F4/50
Filed: 1955-01-18
Abstract: The novel aluminium compounds of formula R2AlX, wherein R is hydrogen or a hydrocarbon radical and X is <FORM:0799823/IV (b)/1> are used as catalyst components in the polymerization of ethylene (see Group IV (a)).  In Example 7 piperidyl diethyl aluminium is prepared by adding 1 mol. of dry piperidine at room temperature to 1 mol. of triethyl aluminium and then heating to 120-140 DEG  C. In Example 8, dimethyl-amino diethyl aluminium is prepared from dimethyl amine and diethyl aluminium hydride, and in Example 9 ethylmercapto diethyl aluminium is obtained from ethyl mercaptan and triethyl aluminium. Other compounds specified are phenoxy-, b -naphthoxy-, methylcyclohexylamino-, dicyclohexylamino- and N-methyl anilino-diethyl aluminium compounds, diethyl aluminiumcaprolactamide, -acetate and benzoate, and diisobutyl aluminium benzoate. Specification 713,081 is referred to.ALSO:Catalysts used in the polymerization of ethylene are formed by mixing an aluminium compound R2AlX, wherein R is hydrogen or a hydrocarbon radical and X is hydrogen, halogen or an alkoxy, aryloxy, sec.-amine, mono-N-substituted amide, mercaptan, thiophenol, carboxylic acid, or a sulphonic acid group, and a compound of a metal of the A sub-groups of groups IV to VI.  In examples, the aluminium compounds used are diethyl aluminium hydride, chloride, sesquichloride and phenolate, triphenyl aluminium, piperidyl diethyl aluminium, methoxy dimethyl aluminium, and diethylamino- and ethyl-mercapto-diethyl aluminium. Other compounds listed include phenoxy- and naphthoxy-diethyl aluminium, dimethylamino - diethyl aluminium (methylcyclohexylamino), diethyl aluminium, (dicyclohexylamino) - diethyl aluminium, (N-methylanilino)-diethyl aluminium, diethyl aluminium caprolactamide, diethyl aluminium acetate, and diethyl- and diisobutyl-aluminium benzoate.  The Group IV (a), V (a) and VI (a) metallic compounds specified are the halides, oxyhalides, complex halides, oxides, hydroxides, alkoxides, acetates, benzoates and acetyl acetonates, e.g. titanium, zirconium and tungsten tetrachlorides and chromous chloride. Specification 713,081, [Group IV (a)], is referred to.ALSO:High molecular weight polyethylene is produced using a catalyst formed by mixing a compound of formula R2AlX, wherein R is hydrogen or a hydrocarbon radical and X is hydrogen, halogen or an alkoxy, aryloxy, sec.-amine, mono-N-substituted amide, mercaptan, thiophenol, carboxylic acid, or a sulphonic acid group, and a compound of a metal of the A subgroups of Groups IV to VI.  In the examples the aluminium compounds used are diethyl aluminium hydride, chloride, sesquichloride and phenolate, triphenyl aluminium, piperidyl diethyl aluminium, methoxy dimethyl aluminium, and diethylamino and ethylmercapto diethyl aluminium, but other compounds listed include phenoxy- and naphthoxy-diethyl aluminium, dimethylamino diethylaluminium (methylcyclohexylamino) - diethyl aluminium, (dicyclohexylamino) - diethyl aluminium, (N - methyl anilino) - diethylaluminium, diethyl aluminium caprolactamide, diethyl aluminium acetate and diethyl- and diisobutyl-aluminium benzoate.  The Group IV to VI metallic compounds disclosed are the halides (chlorides or bromides), oxy-halides (oxychloride), complex halides (complex fluorides), oxides, hydroxides and organic compounds such as alkoxides, acetates, benzoates and acetyl acetonates, and the examples use titanium, zirconium and tungsten tetrachlorides and chromous chloride.  The ethylene, which may be introduced intermittently during the polymerization, may be pure or produced by cracking ethane, propane or petroleum, or in the Fischer-Tropsch synthesis.  Polymerization may be carried out in solution in solvents such as pentane, hexane, cyclohexane, tetrahydronaphthalene, decahydronaphthalene, paraffins, benzene, xylene, o-dichlorbenzene, chlorinated naphthalenes, dibutyl ether, dioxane, tetrahydrofurane and mixtures.  Catalyst formation and polymerization is preferably conducted in an inert atmosphere, e.g. nitrogen.  On completion of polymerization the catalyst may be destroyed with methanol and the product washed with methanol and dilute nitric acid.  The polyethylenes produced are linear, of crystalline structure and have improved physical properties.  They may be stretched while cold and may be formed into films, sheets and filaments.  Specification 713,081 is referred to.