摘要:
A process for the preparation of a supported catalyst for the polymerization of .alpha.-olefins, in which(1) a silicon dioxide-containing support gel is prepared by(1.1) introducing a sodium water glass or potassium water glass solution into a swirling stream of an aqueous mineral acid longitudinally and tangentially to the stream, spraying the resultant silica hydrosol in drop form into a gaseous medium and allowing it to solidify to form a hydrogel, and freeing the resultant hydrogel from salts by washing without prior ageing,(1.2) drying the hydrogel resulting from (1.1) to form the support gel,(2) the support gel (1) is charged with chromium trioxide or a chromium compound which can be converted into chromium trioxide under the conditions of process step (3), giving a chromium-containing support gel, and(3) the chromium-containing support gel (2) is heated at from 400.degree. to 1100.degree. C. for from 10 to 1000 minutes in an anhydrous gas stream containing oxygen in a concentration of greater than 10% by volume,comprises drying the hydrogel resulting from step (1.1) in step (1.2) within a time of not more than 60 seconds in a shaping, high-speed dryer at an inlet temperature of from 80.degree. to 400.degree. C.
摘要翻译:一种制备用于α-烯烃聚合的负载催化剂的方法,其中(1)含二氧化硅的载体凝胶通过(1.1)将钠水玻璃或钾水玻璃溶液引入旋流 将水性无机酸纵向和切向于料流,将所得的二氧化硅水溶胶以液滴形式喷雾到气态介质中并使其固化形成水凝胶,并通过在没有预先熟化的情况下洗涤将所得水凝胶从盐中释放,(1.2)干燥 由(1.1)产生的形成支持凝胶的水凝胶,(2)载体凝胶(1)中加入三氧化铬或铬化合物,其可以在工艺步骤(3)的条件下转化为三氧化铬,得到 含铬载体凝胶,(3)含铬载体凝胶(2)在含有浓度浓度的氧的无水气流中在400〜1100℃下加热10〜1000分钟 大于10体积%包括在入口温度为80°至400°的成形高速干燥器中在不超过60秒的时间内将步骤(1.2)中由步骤(1.1)得到的水凝胶干燥 DEG C.
摘要:
A process for the preparation of a supported catalyst for the polymerization of .alpha.-olefins, in which(1) a silicon dioxide-containing support gel is prepared by(1.1) introducing a sodium water glass or potassium water glass solution into a swirling stream of an aqueous mineral acid longitudinally and tangentially to the stream, spraying the resultant silica hydrosol in drop form into a gaseous medium and allowing it to solidify to form a hydrogel, and freeing the resultant hydrogel from salts by washing without prior ageing,(1.2) drying the hydrogel resulting from (1.1) to form the support gel,(2) the support gel (1) is charged with chromium trioxide or a chromium compound which can be converted into chromium trioxide under the conditions of process step (3), giving a chromium-containing support gel, and(3) the chromium-containing support gel (2) is heated at from 400.degree. to 1100.degree. C. for from 10 to 1000 minutes in an anhydrous gas stream containing oxygen in a concentration of greater than 10% by volume,comprises drying the hydrogel resulting from step (1.1) in step (1.2) within a time of not more than 60 seconds in a shaping, high-speed dryer at an inlet temperature of from 80.degree. to 400.degree. C.
摘要翻译:一种制备用于α-烯烃聚合的负载催化剂的方法,其中(1)含二氧化硅的载体凝胶通过(1.1)将钠水玻璃或钾水玻璃溶液引入旋流 将水性无机酸纵向和切向于料流,将所得的二氧化硅水溶胶以液滴形式喷雾到气态介质中并使其固化形成水凝胶,并通过在没有预先熟化的情况下洗涤将所得水凝胶从盐中释放,(1.2)干燥 由(1.1)产生的形成支持凝胶的水凝胶,(2)载体凝胶(1)中加入三氧化铬或铬化合物,其可以在工艺步骤(3)的条件下转化为三氧化铬,得到 含铬载体凝胶,(3)含铬载体凝胶(2)在含有浓度浓度的氧的无水气流中在400〜1100℃下加热10〜1000分钟 大于10体积%包括在入口温度为80°至400°的成形高速干燥器中在不超过60秒的时间内将步骤(1.2)中由步骤(1.1)得到的水凝胶干燥 DEG C.
摘要:
Homopolymers of ethylene or copolymers of ethylene with minor amounts of other C.sub.3 -C.sub.12 -alk-1-enes are prepared by catalytic polymerization in a suspension or in the gas phase in the presence of an antistatic agent at from 50 to 120.degree. C. and from 5 to 50 bar by a process in which the antistatic agent used is a mixture of the following substances:a) a metal salt of medialanic acid of the formula (I) ##STR1## b) a metal salt of an anthranilic acid of the general formula (II) ##STR2## where the organic radical R.sup.1 is either.alpha.)--CO--(CH.sub.2).sub.x --CH.sub.3 (II.alpha.)or.beta.)--CO--(CH.sub.2).sub.y --CH.dbd.CH--(CH.sub.2).sub.z --CH.sub.3(III.beta.)and x, y and z are each an integer and are from 6 to 18 for x, from 1 to 16 for y, from 1 to 16 for z and from 4 to 17 for y+z, andc) a polyamine obtainable by reacting epichlorohydrin and an aliphatic primary monoamine or an N-alkylalkylenediamine of the general formula (IV)R.sup.2 NH--R.sup.3 --NH.sub.2 (IV),whereR.sup.2 is C.sub.8 -C.sub.24 -alkyl andR.sup.3 is C.sub.2 -C.sub.6 -alkylene.
摘要:
Polyalk-1-enes are prepared by polymerization of alk-1-enes with the aid of the compound bis(cyclopentadienyl)-chromium(II) in which the cyclopentadienyl rings may carry inert organic radicals, said compound being adsorbed on an inorganic oxide carrier, by a process in which the polymerization is carried out in the presence of an organometallic compound of a metal of main groups I to III or of a metal hydride, in particular of n-butyl-lithium.
摘要:
A process is described for preparing polyoxymethylene by contacting a formaldehyde source with a catalyst of the formula I [CpvMLw]m+Zm/nn− (I) where M is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh or Ir, Cp is a cyclopentadienyl ligand C5H(5−u)R1u, where u is from 0 to 5 and R1 is alkyl, alkenyl, aryl, heteroaryl, aralkyl, COOR2, COR2, CN or NO2, and R2 is H, alkyl, aryl or aralkyl, v is 1 or 2, each L is independently a nitrile, CO or a ligand displaceable by CO, w is an integer from 0 to 4, Z is an anion, and m and n are each independently an integer from 1 to 3.
摘要:
Graft copolymers obtained byA) emulsion polymerization of from 5 to 35% by weight of a monomer mixture ofa.sub.1) 60-80% by weight of one or more vinylaromatic monomers,a.sub.2) 20-40% by weight of one or more ethylenically unsaturated nitriles,B) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage A), of 20-45% by weight of a monomer mixture ofb.sub.1) 50-75% by weight of one or more vinylaromatic monomers,b.sub.2) 25-50% by weight of one or more C.sub.1 -C.sub.18 -alkyl acrylates,C) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage B), of 5-35% by weight of a monomer mixture ofc.sub.1) 60-80% by weight of one or more vinylaromatic monomers,c.sub.2) 20-40% by weight of one or more ethylenically unsaturated nitriles,D) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage C), of 15-45% by weight of a monomer mixture ofd.sub.1) 80-99.9% by weight of one or more C.sub.1 -C.sub.18 -alkyl acrylates,d.sub.2) 0.1-0% by weight of one or more di- or polyethylenically unsaturated monomers.The graft copolymers can be used for the preparation of transparent PVC molding materials.
摘要:
Extrudable pharmaceutical mixtures are tableted by a continuous method in which the mixture is extruded and the still deformable extrudate is pressed between two rollers which are driven in opposite directions and possess depressions opposite one another in the roller shell, the form of these depressions determining the tablet shape.
摘要:
Process for the preparation of solid pharmaceutical forms by mixing one or more pharmaceutical active compounds with one or more fusible, pharmacologically tolerated binders and, if required, other conventional pharmaceutical auxiliaries, at from 50.degree. to 180.degree. C., and subjecting the mixture to injection molding or extrusion and shaping, wherein the fusible binder used is a NVP polymer which contains not less than 20% by weight of NVP as copolymerized units, and, where they are present, all of whose comonomers contain nitrogen and/or oxygen.
摘要:
Copolymers of ethylenically unsaturated dicarboxylic anhydrides and alkyl vinyl ethers are prepared by copolymerization of the monomers from which the copolymers are derived, in the presence or absence of up to 2% by weight, based on the monomers, of a crosslinking agent containing two or more ethylenically unsaturated double bonds, in the presence of a polymerization initiator in an ester of not less than 5 carbon atoms which is obtained from a saturated aliphatic carboxylic acid and a saturated monohydric alcohol, as a solvent for the monomers, by a precipitation polymerization method.
摘要:
Copolymers of monoalkyl maleates and vinyl alkyl ethers are prepared by free radical copolymerization of maleic anhydride and a vinyl alkyl ether followed by reaction with an alkanol, by a process in which the vinyl alkyl ether component is present in excess in the reaction mixture in each phase of the polymerization, the free radical copolymerization is carried out in acetone and the acetone is removed by distillation during or after ester formation at up to 70.degree. C.