Abstract: Propylene homopolymers, wherein, in their separation according to tacticity by first dissolving the polymers in boiling xylene, then cooling the solution to 25° C. at a cooling rate of 10° C./h and then, with ascending temperature, separating the propylene homopolymers into fractions of different tacticity, either one or more of the conditions that i) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 112° C. is greater than 20% by weight or ii) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 117° C. is greater than 8% by weight or iii) the fraction of propylene homopolymers which remains undissolved on heating the cooled propylene homopolymer solution to 122° C. is greater than 1% by weight, are satisfied.

Abstract: Propylene polymers contain a) from 50 to 95 parts by weight of a propylene homopolymer having a melt flow index of from 0.1 to 100 g/10 min., at 230° C. and under a weight of 2.16 kg, according to ISO standard 1133, and an isotacticity index of at least 98%, b) from 5 to 50 parts by weight of an ethylene copolymer containing from 4 to 40% by weight of polymerized C4-C20-alk-1-ene and having a density of from 0.865 to 0.920 g/cm3 and c) from 0 to 1.5 parts by weight of a nucleating agent, the sum of the parts by weight of the propylene homopolymer a) and of the ethylene copolymer b) always being 100 parts by weight. The propylene polymers are distinguished in particular by high rigidity and little tendency to white fracture.

Abstract: Propylene polymers contain

Abstract: Propylene polymers contain

Abstract: 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)<542 400 exp (−0.1TM)+0.5  (1),  the tensile modulus of elasticity (E) of the propene copolymer (A′) in MPa, determined in accordance with ISO 527, obeys the inequality (2) (E)>1.9×10−11(TM)6.34+180 MPa  (2),  where in both inequalities (1) and (2) TM is the melting point in ° C.

Abstract: 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.

Abstract: Partially crosslinked plastic compositions with a melt flow index at 230.degree. C. and under a load of 2.16 kg, of from 0.1 to 100 g/10 min, and a gel content of less than 12% by weight, is prepared froma) a polymer comprisinga.sub.1) from 60 to 92% by weight of a propylene homopolymer anda.sub.2) from 8 to 40% by weight of a propylene copolymer having C.sub.2 -C.sub.10 -alk-1-enes incorporated into its polymer chain and with a comonomer content, based on a.sub.2) of from 15 to 70% by weight, andb) a compound of the formula (I) ##STR1## where R.sup.1 is hydrogen or C.sub.1 -C.sub.4 -alkyl,X is substituted or unsubstituted C.sub.1 -C.sub.30 -alkyl or substituted or unsubstituted C.sub.7 -C.sub.30 -arylalkyl, where each of the alkyl groups may be interrupted byone or more oxygen atoms in ether moieties (--O--) or oxycarbonyl moieties (--O--CO--) and/or bynitrogen groups of the formula NR.sup.2, where R.sup.2 is hydrogen, C.sub. -C.sub.6 -alkyl or C.sub.1 -C.sub.

Abstract: Propylene polymers which comprise from 25 to 97% by weight of a propylene polymer (I) containing from 0 to 15% by weight of copolymerized C.sub.2 -C.sub.10 -alk-1-enes and also comprise from 3 to 75% by weight of a further propylene polymer (II) containing from 15 to 80% by weight of copolymerized C.sub.2 -C.sub.10 -alk-1-enes, are obtainable by two-stage polymerization of propylene and C.sub.2 -C.sub.10 -alk-1-enes in the presence of a Ziegler-Natta catalyst system which comprises a titanium-containing solid component a) comprising a compound of magnesium, a halogen, silica gel as support and a carboxylic ester as electron donor compound, and also as cocatalysts an aluminum compound b) and a further electron donor compound c), where, in a first polymerization stage, propylene is polymerized in the presence or absence of further C.sub.2 -C.sub.10 -alk-1-enes at from 50.degree. to 100.degree. C., pressures in the range from 15 to 40 bar and a mean residence time of from 0.

Abstract: Halogen-free flameproofed thermoplastic molding materials based on polyphenylene ethers and polystyrene containing, as essential components,A) from 5 to 92% by weight of one or more polyphenylene ethers,B) from 5 to 92% by weight of a vinylaromatic polymer andC) from 3 to 25% by weight of a flameproofing agent based onC1) from 20 to 100% by weight (based on the total amount of C) of a polymeric phosphorus compound which is obtained by polymerizing or copolymerizing one or more compounds of the following structure: ##STR1## where ##STR2## R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.10 and R.sup.11 are each hydrogen, alkyl, cycloalkyl, aralkyl or aryl,R.sup.7, R.sup.8 and R.sup.9 are each alkylidene, cycloalkylidene, aralkylidene or arylidene,m, p, q, r, s, t, u and v are each 0 or 1,n is 0, 1 or 2,U is COO, O, S or NR.sup.9,V, W, X and Y are each O, S or NR.sup.9 andZ is O, S or NR.sup.10 R.sup.

Abstract: Thermoplastic molding materials contain, based in each case on the sum of components A, B and C,A: from 10 to 90% by weight of a polymer A composed of styrene and/or substituted styrene,B: from 10 to 90% by weight of a polyolefin B andC: from 5 to 40% by weight of a star block copolymer C containing not less than 50% by weight of styrene and prepared by anionic polymerization of styrene and butadiene and/or isoprene, coupling and subsequent selective hydrogenation.

Abstract: A thermoplastic molding material contains, in each case based on the sum of the constituents A, B and C,A: 10 to about 90% by weight of a styrene polymer A,B: 10 to about 90% by weight of a polyolefin B, andC: 1 to 20% by weight of an unsymmetrical linear three-block copolymer C of the structure S.sub.1 -D-S.sub.2, prepared by anionic polymerization from styrene and butadiene and/or isoprene, S.sub.1 and S.sub.2 each denoting a polystyrene block and D denoting a polydiene block,wherein the three-block copolymer C has a styrene content, based on C, of from 50 to 85% by weight and the terminal blocks S.sub.1 and S.sub.2 built up from styrene differ by at least 50% in their molecular weight.