This disclosure relates to a method and an apparatus for the delivery of a multi-component olefin polymerization catalyst to a polymerization reactor. The apparatus includes: a first catalyst component delivery conduit; a second catalyst component delivery conduit which is disposed within the first catalyst component delivery conduit; a first catalyst component mixing conduit; a third catalyst component delivery conduit which is disposed within the first catalyst component mixing conduit; a second catalyst component mixing conduit comprising an upstream section and a downstream section, the downstream section terminating within the polymerization reactor; and a diluent delivery conduit; the first and second catalyst component delivery conduits each being open-ended and co-terminating at the first catalyst component mixing conduit; the first catalyst component mixing conduit and the third catalyst component delivery conduit each being open-ended and co-terminating at the upstream section of the second catalyst component mixing conduit; and the diluent delivery conduit terminating at the downstream section of the second catalyst component mixing conduit.

A procedure for improved temperature control in controlled radical polymerization processes is disclosed. The procedure is directed at controlling the concentration of the persistent radical in ATRP and NMP polymerizations procedures and the concentration of radicals in a RAFT polymerization process by feeding a reducing agent or radical precursor continuously or intermittently to the reaction medium through one of more ports.

A procedure for improved temperature control in controlled radical polymerization processes is disclosed. The procedure is directed at controlling the concentration of the persistent radical in ATRP and NMP polymerizations procedures and the concentration of radicals in a RAFT polymerization process by feeding a reducing agent or radical precursor continuously or intermittently to the reaction medium through one of more ports.

The present invention relates to a method for preparing a polyolefin block copolymer, the method comprising: a first step of coordination polymerization of an olefin monomer with a transition metal catalyst in the presence of organozinc; and a second step of continuously adding a diacyl peroxide compound to perform polymerization, and to a polyolefin block copolymer prepared therefrom.

The present invention relates to a method for preparing a polyolefin block copolymer, the method comprising: a first step of coordination polymerization of an olefin monomer with a transition metal catalyst in the presence of organozinc; and a second step of continuously adding a diacyl peroxide compound to perform polymerization, and to a polyolefin block copolymer prepared therefrom.

A modified conjugated diene-based polymer having high Mooney viscosity and good shape stability and exhibiting excellent processability and low heat build-up is obtained in as few steps as possible. The modified conjugated diene-based polymer is produced by a method of reacting a conjugated diene-based polymer having an active chain end, obtained by polymerizing a monomer containing a conjugated diene compound in the presence of an initiator that contains at least either of an alkali metal compound and an alkaline earth metal compound, with a compound [M] having at least two groups selected from the group consisting of a group C(R.sup.1)N-A.sup.1 and a group NC(R.sup.1)-A.sup.1, where R.sup.1 is a hydrogen atom or a hydrocarbyl group and A.sup.1 is a monovalent group having an alkoxysilyl group.

A prepolymerized catalyst component for the polymerization of olefins made from or containing (i) a solid catalyst component made from or containing Ti, Mg, and an internal donor mixture (IDM) made from or containing (a) from 15 to 75% of 1,3-diethers and (b) from 25 to 85% of succinates based on the total amount of 1,3-diethers and succinates, and (ii) an amount of an ethylene polymer ranging from 0.1 up to 3 g per g of the solid catalyst component (i), wherein the prepolymerized catalyst component has an intrinsic viscosity [?] in tetraline at 135? C. ranging from 2.5 to 5.20 dl/g.

A prepolymerized catalyst component for the polymerization of olefins made from or containing (i) a solid catalyst component made from or containing Ti, Mg, and an internal donor mixture (IDM) made from or containing (a) from 15 to 75% of 1,3-diethers and (b) from 25 to 85% of succinates based on the total amount of 1,3-diethers and succinates, and (ii) an amount of an ethylene polymer ranging from 0.1 up to 3 g per g of the solid catalyst component (i), wherein the prepolymerized catalyst component has an intrinsic viscosity [?] in tetraline at 135? C. ranging from 2.5 to 5.20 dl/g.

A polymerization initiator-containing composition contains a fourth period transition metal compound including a transition metal atom belonging to the fourth period of the Periodic Table, a tertiary amine compound, and a thiourea compound represented by the following general formula (1):

##STR00001##

where R.sup.1 to R.sup.4 each represent one selected from the group consisting of a hydrogen atom, an alkyl group, an aromatic ring group, and a heterocyclic group.

The present invention relates to a modified conjugated diene-based polymer, a method of preparing the same, and a rubber composition including the same, and more specifically provides a rubber composition which includes a repeating unit derived from a conjugated diene-based monomer having a trans-1,4 bond content of 80 wt % or more and a functional group derived from an alkoxysilane-based modifier, a method of preparing the same, and a rubber composition including the same.