Polymerisationsverfahren

摘要

1,176,717. Boron-type polymerization catalysts for ethylene. E.I. DU PONT DE NEMOURS & CO. 2 May, 1967 [2 May, 1966], No. 20307/67. Heading C3P. Polyethylene or copolymers of ethylene with one or more ethylenically unsaturated comonomers are made by effecting the polymerization of the monomers at a pressure of at least 200 atmospheres and a temperature between 100‹ and 250‹ C. in the presence of an initiating system consisting of (1) a boron compound selected from B 2 H 6 , RBH 2 BH 2 R, R 2 BHBHR 2 , R1 3 B, R1 3 N.BH 3 , R1 2 NH.BH 3 , or R11 3 P.BH 3 , where R is an alkyl group of 1 to 9 carbon atoms, R1 is an alkyl group of 1 to 12 carbon atoms and R11 is selected from alkyl, aryl or alkaryl, each of up to 12 carbon atoms, and (ii) a compound selected from (a) nitric oxide, (b) compounds of the formula wherein Ar and Ar1 each containing 6 to 12 carbon atoms are selected from aryl, alkylphenyl, alkoxyphenyl, or halophenyl in which the halogen is of atomic number 9 to 35, and Aq is a substituted phenyl group containing at least 2 and at most 3 nitro groups in the 2-, 4- and 6-positions and which can contain one substituent selected from -COOM, -SO 3 M, halogen of atomic number 9 to 35, lower alkyl, or lower alkoxy and in which M is hydrogen or alkali metal, (c) an N-nitrosodiarylamine of the formula wherein Ar11 and Ar111 each contain 6 to 12 carbon atoms and are selected from aryl, lower alkylaryl, di-(lower alkyl)-aryl, mono- or dilower alkoxyaryl, haloaryl, dihaloaryl or alkylhaloaryl in which each halogen is of atomic number 9 to 35, (d) compounds of the formula U-NO, where U is aryl of 6 to 12 carbon atoms, lower alkylphenyl, lower alkoxyphenyl, or halophenyl in which the halogen is of atomic number 9 to 35, (e) compounds of the formula U1 2 N-NU112, wherein U1 and U11 are phenyl or naphthyl, (f) nitroxides of the formula wherein Q is a tertiary alkyl of 4 to 6 carbon atoms or a 2,6-di-(lower alkoxy) phenyl, and Q1 is Q, 2-phenyl-2-propyl, or, when Q is 2,6-di- (lower alkoxy) phenyl, 4-(lower alkoxy-phenyl), (g) tertiary alkyl nitrites of 4 to 8 carbon atoms, (h) nitrite salts wherein the cation is ammonium, an alkali metal, or an alkaline-earth metal, (i) the ammonium salts of N-nitrosophenylhydroxylamine or (j) poly-(tert.-alkyl) phenoxyls, wherein the tert.-alkyl group contains 4 to 6 carbon atoms. The Specification contains extensive lists of compounds in accordance with the above classes. The comonomers may be selected from lower olefins containing a terminal methylene group, fluorinated olefins containing 2 or 3 carbon atoms, vinyl alkanecarboxylates, lower alkyl methacrylates, styrene and ring- substituted styrenes, dicyclopentadiene and di- (methyl-cyclopentadiene), non-conjugated dienes, carbon monoxide, and sulphur dioxide. The polymerization may be effected in bulk or in the presence of a hydrocarbon or fluorinated hydrocarbon solvent. Preferred boron compounds are trimethylamine-borane, triethyl borane, diborane, tri-n-butyl borane, dimethylamine borane, triphenyl phosphine borane, trin-butyl phosphine borane, and 1,2-di-(1,1-dimethyl - 2 - methylprop - 1 - yl) diborane. Preferred cocatalysts are nitric oxide, 1,1-diphenyl - 2 - picrylhydrazyl, N - nitrosodiphenylamine, nitrosobenzene, tetraphenylhydrazine, di - tert. - butylnitroxide, sodium nitrite, ammonium nitrite, and 2,4,6 - tris - (tert. - butyl) phenoxyl.