A process for the preparation of a propylene polymer containing a coloring agent, including the steps of:

(i) forming a solid mixture (a-b)of (a) a ZN catalyst component made from or containing Mg, Ti, halogen and an internal electron donor compound, and (b) a coloring agent made from or containing at least a pigment; wherein the mixture being in a weight ratio (b):(a) ranging from 0.01:1 to 0.4:1; and

(ii) feeding the mixture (a-b) to a polymerization reactor and operating the reactor under polymerization conditions to produce the propylene polymer.

wherein the process having the b:a weight ratio and a time in days elapsed between mixture formation and use in polymerization fall below the curve defined by the equation y=3+0.832x.sup.−1,17 wherein y is the time in days elapsed between mixture formation and use in polymerization and x is the (b):(a) weight ratio.

A process for the preparation of a propylene polymer containing a coloring agent, including the steps of:

(i) forming a solid mixture (a-b)of (a) a ZN catalyst component made from or containing Mg, Ti, halogen and an internal electron donor compound, and (b) a coloring agent made from or containing at least a pigment; wherein the mixture being in a weight ratio (b):(a) ranging from 0.01:1 to 0.4:1; and

(ii) feeding the mixture (a-b) to a polymerization reactor and operating the reactor under polymerization conditions to produce the propylene polymer.

wherein the process having the b:a weight ratio and a time in days elapsed between mixture formation and use in polymerization fall below the curve defined by the equation y=3+0.832x.sup.−1,17 wherein y is the time in days elapsed between mixture formation and use in polymerization and x is the (b):(a) weight ratio.

Disclosed are a method and system for propylene polymerization utilizing a loop slurry reactor. The method can include polymerizing propylene in a loop slurry reactor under bulk polymerization conditions to produce polypropylene. The propylene polymerization system can include i) a loop slurry reactor and a heat exchange system that is configured to cool the legs of the loop slurry reactor and/or ii) an inlet manifold that is configured to connect flashline heaters to a separator.

Disclosed are a method and system for propylene polymerization utilizing a loop slurry reactor. The method can include polymerizing propylene in a loop slurry reactor under bulk polymerization conditions to produce polypropylene. The propylene polymerization system can include i) a loop slurry reactor and a heat exchange system that is configured to cool the legs of the loop slurry reactor and/or ii) an inlet manifold that is configured to connect flashline heaters to a separator.

Disclosed is a catalyst component for olefin polymerization. The catalyst component comprises magnesium, titanium, halogen and an internal electron donor. The internal electron donor includes an imine compound with a ketone group as shown in Formula I. Disclosed further is a method of preparing the catalyst component, and a catalyst for olefin polymerization containing the catalyst component. When the catalyst is used in olefin polymerization reaction especially propene polymerization reaction, the catalyst has a high activity and a long term activity and good hydrogen response, and the obtained polymer has characteristics of an adjustable isotactic index and a relatively wide molecular weight distribution. ##STR00001##

Disclosed is a catalyst component for olefin polymerization. The catalyst component comprises magnesium, titanium, halogen and an internal electron donor. The internal electron donor includes an imine compound with a ketone group as shown in Formula I. Disclosed further is a method of preparing the catalyst component, and a catalyst for olefin polymerization containing the catalyst component. When the catalyst is used in olefin polymerization reaction especially propene polymerization reaction, the catalyst has a high activity and a long term activity and good hydrogen response, and the obtained polymer has characteristics of an adjustable isotactic index and a relatively wide molecular weight distribution. ##STR00001##

Methods for producing polyethylene compositions having broader melt index ratio and narrower molecular weight distribution in high pressure multi-feed tubular reactors are provided. The methods are useful in multi-feed tubular reactors comprising three or more reaction zones. The first reaction zone or the first and second reaction zone having a peak temperature that is lower than standard peak temperatures for polymerization of ethylene monomer in a tubular reactor.

Methods for producing polyethylene compositions having broader melt index ratio and narrower molecular weight distribution in high pressure multi-feed tubular reactors are provided. The methods are useful in multi-feed tubular reactors comprising three or more reaction zones. The first reaction zone or the first and second reaction zone having a peak temperature that is lower than standard peak temperatures for polymerization of ethylene monomer in a tubular reactor.

Methods for producing polyethylene compositions having broader melt index ratio and narrower molecular weight distribution in high pressure multi-feed tubular reactors are provided. The methods are useful in multi-feed tubular reactors comprising three or more reaction zones. The first reaction zone or the first and second reaction zone having a peak temperature that is lower than standard peak temperatures for polymerization of ethylene monomer in a tubular reactor.

The present disclosure relates to a polypropylene resin exhibiting excellent processability and capable of producing fine fibers, a polypropylene fiber including the same, and a method for preparing the same.