摘要:
In a process for the polymerization of C2-C8-alk-1-enes by means of a Ziegler-Natta catalyst system, in which polymerization is carried out from the gas phase in at least one reaction zone at from 40 to 120° C. and pressures of from 1 to 100 bar, the pressure and temperature in the reaction zone are set so that an operating point formed by these parameters in a pressure-temperature diagram is located at from 0.2 to 5.0 bar below the dew line of the respective reaction mixture above which condensation of the C2-C8-alk-1-enes occurs.
摘要:
Propylene polymers containing a matrix of a propylene homopolymer and a copolymer of propylene and other alkenes, wherein, during the separation of the propylene polymers according to tacticity and comonomer distribution of the polymer chains, by first dissolving the propylene polymers in boiling xylene, then cooling the solution at a cooling rate of 10° C./h to 25° C. and thereafter, increasing the temperature, separating the propylene polymers into fractions of different solubility, either one or more of the conditions that i) more than 20% by weight of the matrix remain undissolved on further heating to 112° C. or ii) more than 8% by weight of the matrix remain undissolved on further heating to 117° C. or iii) more than 1% by weight of the matrix remain undissolved on further heating to 122° C. are fulfilled by the matrix which remains undissolved on heating the cooled propylene polymer solution to 80° C., a process for the preparation of the propylene polymers, their use for the production of films, fibers or moldings and the films, fibers or moldings comprising these propylene polymers, are described.
摘要:
In catalyst systems of the Ziegler-Natta type modified during their preparation and comprising as active constituentsa) a titanium-containing solid component which is obtained by reacting a compound of titanium with a compound of magnesium, a halogen, an inorganic oxide as support, a C.sub.1 -C.sub.8 -alkanol and a carboxylic ester as electron donor compound,and also as cocatalystb) an aluminum compound andc) if desired, a further electron donor compound,the titanium-containing solid component a) is prepared by first, in a first stage, admixing an inorganic oxide as support with a solution of a chlorine-free compound of magnesium in an inert solvent, stirring this mixture for from 0.5 to 5 hours at from 10 to 120.degree. C. and subsequently reacting it while stirring continually in an inert solvent with a C.sub.1 -C.sub.8 -alkanol in an at least 1.3-fold excess, based on the compound of magnesium, to give a chlorine-free intermediate, then, without purification or extraction of the intermediate, adding a compound of trivalent or tetravalent titanium and a carboxylic ester as electron donor compound to this intermediate, stirring the resulting mixture for at least 30 minutes at from 20 to 130.degree. C., subsequently filtering off and washing the solid thus obtained and subsequently, in a second stage, extracting the solid obtained from the first stage in an inert solvent comprising at least 5% by weight of titanium tetrachloride and washing it with a liquid alkane.
摘要:
Multiphase homo- or copolymers of C2-C10-alk-1-enes are prepared by a process in which polymerization is effected in the presence of two different catalyst systems in one reaction zone, one of the catalyst systems containing, as active components, a metallocene complex of the general formula (I) or (II) where M1 is a metal of group IVb, Vb or VIb of the Periodic Table, R1 and R2 are identical or different and are each hydrogen, C1-C10-alkyl, C1-C10-alkoxy, C6-C10-aryl, C6-C10-aryloxy, C2-C10-alkenyl, C7-C40-arylalkyl, C7-C40-alkylaryl, C8-C40-arylalkenyl or halogen, R3 and R4 are identical or different and are each hydrogen, halogen, C1-C10-alkyl which may be halogenated, C6-C10-aryl or an —NR210, —SR10, —OSiR310, —SiR310 or —PR210 radical, where R10 is halogen, C1-C10-alkyl or C6-C10-aryl, and R5 and R6 are identical or different and have the meanings stated for R3 and R4, with the proviso that R5 and R6 are not hydrogen.
摘要:
Polymers of propene consist of from 50 to 99.9% by weight of an isotactic propene copolymer (A′) and from 0.1 to 50% by weight of a propene homopolymer or a propene copolymer (B′), where a) the propene copolymer (A′) consists of from 80 to 99.9 mol % of propene and from 0.1 to 20 mol % of ethene and/or a C4-C12-1-olefin, at least 80% of all propene diads are isotactic meso diads, the propene copolymer (A′) has a proportion (XS) of material soluble in xylene at 20° C. which satisfies the inequality (1) (XS) 1.9×10−11(TM)6.34+180 MPa (2), where in both inequalities (1) and (2) TM is the melting point in ° C., and b) the propene homopolymer or the propene copolymer (B′) consists of from 80 to 100 mol % of propene and from 0 to 20 mol % of ethene and/or a C4-C12-1-olefin, at least 55% of all regioregular propene diads are isotactic meso diads, an enthalpy of fusion &Dgr;Hm of less than 50 J/g is observed in the DSC measurement of (B′) and no crystalline ex sequences are detectable.
摘要:
Transition metal complexes of the formula (Ia) or (Ib), in which the substituents and indices have the following meanings: M is titanium, zirconium, hafnium, vanadium, niobium or tantalum or an element of the third subgroup of the Periodic Table or of the lanthanoids, X is fluorine, chlorine, bromine, iodine, hydrogen, C1-C10-alkyl, C6-C15-aryl, alkylaryl having 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atoms in the aryl radical, —OR5 or —NR5R6, n is 1, 2 or 3, where n is the valency of M minus the number 2, Z is a three-way bridge and A and A1 are two-way bridges. Process for preparing the transition metal complexes, compounds which are used as intermediates for their preparation, the use of the transition metal complexes for polymerizing olefins, processes for polymerizing olefins, homo- or copolymers of ethylene or of propylene with other C2-C12-alk-1-enes, their use for preparing films, fibers or moldings and the films, fibers or moldings made of these polymers.
摘要:
Random copolymers of propylene with other 1-alkenes having up to carbon atoms, whose content of comonomers is in the range from 0.7 to 1.4% by weight if the only comonomer present in the propylene copolymers is ethylene, or whose content of comonomers is in the range from 0.7 to 3.0% by weight if at least one C4-C10-1-alkene is present as comonomer, and whose cold-xylene-soluble fraction is from 1.0 to 2.5% by weight if ethylene is present as a comonomer in the propylene copolymers, or whose cold-xylene-soluble fraction is from 0.75 to 2.0% by weight if the only comonomers present are C4-C10-1-alkenes, and a process for preparing the random copolymers of propylene is described, as is their use for producing films, fibers or moldings, and also the films, fibers and moldings themselves and biaxially stretched films made from random propylene copolymers of this type and processes for their production.
摘要:
Random copolymers of propylene with other 1-alkenes having up to carbon atoms, whose content of comonomers is in the range from 0.7 to 1.4% by weight if the only comonomer present in the propylene copolymers is ethylene, or whose content of comonomers is in the range from 0.7 to 3.0% by weight if at least one C4-C10-1-alkene is present as comonomer, and whose cold-xylene-soluble fraction is from 1.0 to 2.5% by weight if ethylene is present as a comonomer in the propylene copolymers, or whose cold-xylene-soluble fraction is from 0.75 to 2.0% by weight if the only comonomers present are C4-C10-1-alkenes, and a process for preparing the random copolymers of propylene is described, as is their use for producing films, fibers or moldings, and also the films, fibers and moldings themselves and biaxially stretched films made from random propylene copolymers of this type and processes for their production.
摘要:
Polymers of C.sub.2 -C.sub.12 -alkenes are prepared at from -50 to 300.degree. C. and from 0.5 to 3000 bar in the presence of a catalyst system by a process in which a compound of the general formula I ##STR1## where M.sup.1 is boron, aluminum, gallium, indium or thallium andR.sup.1 and R.sup.2 are each hydrogen, C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl, alkylaryl or arylalkyl each having 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atoms in the aryl radical, or 5- to 7-membered cycloalkyl which in turn may carry C.sub.1 -C.sub.10 -alkyl as a substituent, or R.sup.1 and R.sup.2 together form a cyclic group, is added of 4 to 15 carbon atoms.
摘要:
The conversion of the achiral meso form of an ansa-metallocene complex into the chiral rac form is carried out photochemically in the presence of a chiral auxiliary reagent.