A process for propylene preliminary polymerization in liquid phase that occurs in a continuous preliminary polymerization reactor may include feeding a propylene monomer and a Ziegler-Natta catalyst system having (a) a pro-catalyst having an internal electron donor comprising a substituted phenylene aromatic diester, (b) a catalyst activator and optionally (c) an external donor, into the continuous preliminary polymerization reactor, wherein the feeding is carried out without pre-contact of the pro-catalyst with the catalyst activator, and also without pre-contact of the catalyst activator with the propylene monomer before entering the continuous preliminary polymerization reactor.

A process for propylene preliminary polymerization in liquid phase that occurs in a continuous preliminary polymerization reactor may include feeding a propylene monomer and a Ziegler-Natta catalyst system having (a) a pro-catalyst having an internal electron donor comprising a substituted phenylene aromatic diester, (b) a catalyst activator and optionally (c) an external donor, into the continuous preliminary polymerization reactor, wherein the feeding is carried out without pre-contact of the pro-catalyst with the catalyst activator, and also without pre-contact of the catalyst activator with the propylene monomer before entering the continuous preliminary polymerization reactor.

The present disclosure discloses an arylaminosilane compound, a propylene polymerization catalyst and preparation thereof. The arylaminosilane compound has a structure of ##STR00001##
wherein R.sub.1 is a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 silanyl group; R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently H or a C.sub.1-C.sub.12 alkyl group; R.sub.7, R.sub.8 and R.sub.9 are each independently a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 alkoxy group. When the arylaminosilane compound is used as an external electron donor of a propylene polymerization catalyst in propylene polymerization reaction, the catalyst has good hydrogen response.

The present disclosure discloses an arylaminosilane compound, a propylene polymerization catalyst and preparation thereof. The arylaminosilane compound has a structure of ##STR00001##
wherein R.sub.1 is a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 silanyl group; R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently H or a C.sub.1-C.sub.12 alkyl group; R.sub.7, R.sub.8 and R.sub.9 are each independently a C.sub.1-C.sub.8 alkyl group or a C.sub.1-C.sub.8 alkoxy group. When the arylaminosilane compound is used as an external electron donor of a propylene polymerization catalyst in propylene polymerization reaction, the catalyst has good hydrogen response.

Provided are a metallocene supported catalyst capable of greatly reducing generation of fine powder during preparation of olefin polymers while exhibiting excellent catalyst activity, and a method of preparing olefin polymers using the same.

Provided are a metallocene supported catalyst capable of greatly reducing generation of fine powder during preparation of olefin polymers while exhibiting excellent catalyst activity, and a method of preparing olefin polymers using the same.

A heterophasic propylene ethylene copolymer composition having an MFR.sub.2 in the range from 1.0 to 55.0 g/10 min and a melting temperature in the range from 155 to 162° C., comprising: i) from 60 to 88 wt.-% of a xylene cold insoluble fraction (XCI) having an intrinsic viscosity iV(XCI) in the range from 1.40 to 2.50 dl/g, an isotactic pentad concentration [mmmm] of more than 97.0% and a content of 2,1-regiodefects in the range from 0.1 to 0.4 mol %, ii) from 12 to 40 wt.-% of a xylene cold soluble fraction (XCS) having an intrinsic viscosity iV(XCS) in the range from 1.80 to 3.20 dl/g and an ethylene content C2(XCS) in the range from 25 to 80 wt.-%, wherein the ratio of the intrinsic viscosities of the two fractions, iV(XCS)/iV(XCI), is in the range from 1.0 to 2.0.

A heterophasic propylene ethylene copolymer composition having an MFR.sub.2 in the range from 1.0 to 55.0 g/10 min and a melting temperature in the range from 155 to 162° C., comprising: i) from 60 to 88 wt.-% of a xylene cold insoluble fraction (XCI) having an intrinsic viscosity iV(XCI) in the range from 1.40 to 2.50 dl/g, an isotactic pentad concentration [mmmm] of more than 97.0% and a content of 2,1-regiodefects in the range from 0.1 to 0.4 mol %, ii) from 12 to 40 wt.-% of a xylene cold soluble fraction (XCS) having an intrinsic viscosity iV(XCS) in the range from 1.80 to 3.20 dl/g and an ethylene content C2(XCS) in the range from 25 to 80 wt.-%, wherein the ratio of the intrinsic viscosities of the two fractions, iV(XCS)/iV(XCI), is in the range from 1.0 to 2.0.

The present invention relates to heterophasic polypropylene compositions comprising a propylene homo- or copolymer forming a crystalline fraction as a matrix and an amorphous propylene ethylene elastomer as a soluble fraction dispersed in said matrix. The heterophasic polypropylene compositions further comprise an elastomeric ethylene/alpha-olefin random copolymer. The heterophasic polypropylene compositions have a well-balanced relation between stiffness and impact strength, low volatile and semi-volatile emissions and good processability.

The present invention relates to heterophasic polypropylene compositions comprising a propylene homo- or copolymer forming a crystalline fraction as a matrix and an amorphous propylene ethylene elastomer as a soluble fraction dispersed in said matrix. The heterophasic polypropylene compositions further comprise an elastomeric ethylene/alpha-olefin random copolymer. The heterophasic polypropylene compositions have a well-balanced relation between stiffness and impact strength, low volatile and semi-volatile emissions and good processability.