| 摘要 |
Living polymers of one or more monomers of the general formula, CH2=CXY, where X is a hydrogen atom or an organic radical and Y is an organic radical, and the sum of Hammett's value of para-substituents for X and Y is in the range from - 0.2 to 0.1, are made by adding one or more of the monomers to a combination of an alkali metal and a stoichiometrically deficient amount with respect to the alkali metal of an activator selected from condensed ring aromatic hydrocarbons, polynuclear non-condensed ring aromatic hydrocarbons, hydrocarbon compounds having two or more condensed ring systems bonded together, conjugated unsaturated heterocyclic compounds and diaryl ketones, and a Lewis base at a temperature within the range of - 100 DEG to 30 DEG C., in an inert atmosphere, so that an excess of alkali metal over the activator always remains in the polymerization reaction mixture. The polymerizable mix may include ethylenically-unsaturated comonomers in which the Hammett's substituent constant of X1 and Y1 is in the range of - 0.2 to 0.7. The Lewis-bases include ethers, acetals and tertiary amines. The living polymers are "killed" by adding a large amount of a terminating agent such as water, alcohols, Lewis acids, and other agents which introduce functional groups such as CO2, O2, HCHO, CS2, and C2H4O. In Example I, butadiene is polymerized at - 70 DEG C. in the presence of a sodium complex of o-terphenyl, a large excess of Na and tetrahydrofurane, in Example II, under the same conditions as Example I, prior to recovery of the polymer, ethylene oxide was added under agitation at - 70 DEG C., and subsequently polybutadiene glycol recovered, Example III was as Example I, except that the polymerization was effected at 0 DEG C., Example IV was as Example III except that powdered CO2 was added under agitation and solid polybutadiene carboxylic acid recovered, in Example V, isoprene was polymerized in the presence of 1,2-dimethoxyethane, naphthalene and lithium, and the reaction terminated with glacial acetic acid and 1,2-dimethoxyethane, in Example VI, styrene was polymerized and recovered as in Example V, in Example VII styrene was polymerized in the presence of dioxane, biphenyl, and sodium, and in Example VIII styrene and butadiene were polymerized in the presence of a potassium mirror, tetrahydrofuran, and after treating the product with excess CO2 and HCl, a mixture of mono- and di-carboxylic acids of a styrene-butadiene copolymer were recovered.
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