摘要:
A method is disclosed for the reduction of the extractability of trialkanolamines from polyolefins containing such compounds e.g. as a result of the use of trialkanolamines as catalyst deactivators in processes for the polymerization of olefins. Zinc oxide and/or zeolite molecular sieves are incorporated into the polyolefin, either during the process for the manufacture of the polyolefin or subsequent to such manufacture. Zinc oxide may be used in amount of 0.01-4 parts by weight and zeolite molecular sieves in amounts of 0.05-1 parts by weight, per 100 parts of polyolefin. The resultant compositions may be more acceptable for use in the fabrication of articles intended for the packaging of e.g. foodstuffs.
摘要:
A solution polymerization process for the preparation of high molecular weight polymers of alpha-olefins selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and C.sub.4 -C.sub.12 alpha-olefins is disclosed. The process comprises feeding monomer(s), coordination catalyst and inert hydrocarbon solvent to a reactor, polymerizing the monomers at a temperature of up to 320.degree. C. and a pressure of less than 25 MPa, and deactivating the catalyst in the solution so obtained. The catalyst is deactivated by sequentially admixing therewith a minor amount of a nitrogenous base, especially an aqueous solution of such a base, followed by a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The ratio of water:nitrogenous base should not be greater than 5. The hydrocarbon solvent and other volatile matter are then separated from the resultant solution and a composition comprising said high molecular weight polymer is recovered. The amount of nitrogenous base plus any water is not more than 2.5 moles per mole of halogen plus alkyl radicals in the coordination catalyst.
摘要:
A solution polymerization process for the preparation of high molecular weight polymers of alpha-olefins is disclosed. In the process, the coordination catalyst is deactivated using a solution of at least one trialkanolamine deactivating agent of the formula N(ROH)(R'OH).sub.2 where R is isopropyl and R' is alkyl of 2-4 carbon atoms, especially ethyl or isopropyl. The process is capable of producing polyers of improved color.
摘要:
The present invention relates to a solution polymerization process for the preparation of high molecular weight polymers of .alpha.-olefins selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and C.sub.3 -C.sub.12 .alpha.-olefins. The process comprises feeding monomer, coordination catalyst containing vanadium and inert hydrocarbon solvent to a reactor, polymerizing the monomer at a temperature in the range of 105.degree.-320.degree. C. and a pressure of less than 25 MPa and deactivating the catalyst in the solution so obtained by admixing therewith a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The hydrocarbon solvent is then separated from the resultant solution and a composition comprising high molecular weight polymer is recovered. Any catalyst residues remain with the polymer. A particular salt is the salt of a C.sub.8 aliphatic acid, especially calcium 2-ethyl hexanoate.
摘要:
A solution process for the preparation of high molecular weight polymers of alpha-olefins selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and C.sub.3 -C.sub.12 higher alpha-olefins is disclosed. Ethylene and/or mixtures of ethylene and C.sub.3 -C.sub.12 higher alpha-olefins are polymerized under non-isothermal conditions in a tubular reactor or in a system of reactors which operate under different conditions, in the presence of a catalytic amount of a titanium-containing coordination catalyst in an inert solvent at a temperature in excess of 105.degree. C. The improvement is characterized in that:(a) the catalyst is activated with a solution of a mixture of aluminum alkyl and alkoxy aluminum alkyl in inert solvent; and(b) the process is controlled by adjusting the ratio of aluminum alkyl to alkoxy aluminum alkyl in the mixture of (a). The aluminum alkyl is of the formula AlR.sub.n X.sub.3-n and the alkoxy aluminum alkyl is of the formula AlR'.sub.m OR".sub.3-m, in which each of R, R' and R" is alkyl or aryl of 1-20 carbon atoms, X is halogen, n is 2-3 and m is 0-3.
摘要:
A solution polymerization process for the preparation of high molecular weight polymers selected from the group consisting of homopolymers of ethylene and copolymers of ethylene and butene-1 is disclosed. The process comprises feeding monomer(s), coordination catalyst and inert hydrocarbon solvent to a reactor, polymerizing the monomers at a temperature of up to 320.degree. C. and a pressure of less than 25 MPa, and deactivating the catalyst in the solution so obtained. The catalyst is deactivated by sequentially admixing therewith a minor amount of dimethyl carbonate followed by a solution of a salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic acid dissolved in hydrocarbon solvent. The hydrocarbon solvent and other volatile matter are then separated from the resultant solution and a composition comprising the high molecular weight polymer is recovered. The amount of dimethyl carbonate is not more than 2.5 moles, per mole of halogen plus alkyl radicals in the coordination catalyst.
摘要:
A solution process, and a catalyst therefor, for the preparation of high molecular weight polymers of alph-olefins viz. homopolymers of ethylene and copolymers of ethylene and C.sub.3 -C.sub.12 alpha-olefins, is disclosed. The process is operated under solution polymerization conditions at 105.degree.-320.degree.. The catalyst is obtained from titanium tetrahalides, vanadium oxytrihalides and organoaluminum compounds, in which an admixture of catalyst components is heat-treated at 150.degree.-320.degree. C., and activated with an aluminoxane. The catalyst has good activity and the polymer obtained has improved color.
摘要:
A method and apparatus for the monitoring and control of concentration of an ion in a solution at an elevated temperature of at least 100.degree. C. are disclosed. The method comprises the steps of contacting a first electrode with a flowing first solution containing said ion at the elevated temperature, and contacting a second electrode with a second flowing solution containing said ion at the elevated temperature. The rate of flow of the second solution is substantially lower than the rate of flow of the first solution. The first and second solutions are then contacted or admixed. The electrodes must be capable of detecting the ion at the elevated temperature and have the same response characteristics to changes in concentration of the ion at the elevated temperature. The concentration of the ion in the second solution is measured at a temperature lower than the elevated temperature under conditions permitting accurate measurement of the concentration of the ion, and the concentration of the ion in the first solution is monitored and controlled by adjusting the concentration of the ion in at least one of the first and second solutions. The method is particularly adapted for the monitoring and control of salt solutions used in the manufacture of polyamides, using palladium hydride electrodes.
摘要:
A solution process, and a catalyst therefor, for the preparation of high molecular weight polymers of alpha-olefins viz. homopolymers of ethylene and copolymers of ethylene and C.sub.3 -C.sub.12 alpha-olefins, is disclosed. The process is operated under solution polymerization conditions at 105.degree.-320.degree. C. The catalyst is obtained from titanium tetrahalides, vanadium oxytrihalides and organoaluminum compounds, in which an admixture of catalyst components is heat-treated at 180.degree.-250.degree. C. and subsequently cooled to a temperature of less than 150.degree. C. Additional vanadium oxytrihalide is then added. The resultant catalyst solution is activated with an aluminum compound. The catalyst has good activity, showing superior activity to catalysts in which additional vanadium oxytrihalide is not added or added at temperatures above 150.degree. C.
摘要:
A method and apparatus for the monitoring and control of concentration of an ion in a solution at an elevated temperature of at least 100.degree. C. are disclosed. The method comprises the steps of contacting a first electrode with a flowing first solution containing said ion at the elevated temperature, and contacting a second electrode with a second flowing solution containing said ion at the elevated temperature. The rate of flow of the second solution is substantially lower than the rate of flow of the first solution. The first and second solutions are then contacted or admixed. The electrodes must be capable of detecting the ion at the elevated temperature and have the same response characteristics to changes in concentration of the ion at the elevated temperature. The concentration of the ion in the second solution is measured at a temperature lower than the elevated temperature under conditions permitting accurate measurement of the concentration of the ion, and the concentration of the ion in the first solution is monitored and controlled by adjusting the concentration of the ion in at least one of the first and second solutions. The method is particularly adapted for the monitoring and control of salt solutions used in the manufacture of polyamides, using palladium hydride electrodes.