The present invention relates to a method for preparing a liquid rubber, and relates to a method for preparing a liquid rubber, including performing polymerization reaction of a conjugated diene-based monomer in the presence of an organic solvent and a catalyst composition (S10), wherein the catalyst composition includes a catalyst including a compound represented by the following Formula 1, and a liquid rubber prepared therefrom:

##STR00001## wherein R, R.sub.1 to R.sub.4, and o, p, q and r are described herein.

A method of making an olefin polymerization catalyst carrier with a general structure formula of Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, wherein: 0≤n≤2, and R.sup.I and R.sup.II can be the same or different and are each independently selected from a C.sub.1-C.sub.20 hydrocarbon group by reacting an alcohol with a metal magnesium powder under the protection of nitrogen in the presence of a halogen or a halogen-containing compound to obtain a first product, and subjecting the product to a treatment pressure of from 0.2 to 5.0 MPa at a treatment temperature of from 80 to 200° C. for a duration of between 2 minutes and 6 hours. Also provided is a method of making an olefin polymerization solid catalyst component which includes the catalyst carrier, a titanium compound, and at least one electron donor compound.

A method is described for the formation of an active catalyst system for use in the in-line bulk polymerization of polydienes. The method provides a homogeneous, active catalyst system which is capable of being transported to a polymerization reactor for use without causing blockages in piping, thereby saving time and production costs. The catalyst system is formed in-line in a continuous method to avoid prolonged storage periods of the catalyst that can otherwise lead to degradation and disposal of the aged catalyst system.

A method is described for the formation of an active catalyst system for use in the in-line bulk polymerization of polydienes. The method provides a homogeneous, active catalyst system which is capable of being transported to a polymerization reactor for use without causing blockages in piping, thereby saving time and production costs. The catalyst system is formed in-line in a continuous method to avoid prolonged storage periods of the catalyst that can otherwise lead to degradation and disposal of the aged catalyst system.

Provided is a method of preparing a rubber composition, which includes (a) reacting a conjugated diene-based monomer with one or more of compounds in the presence of a first catalyst; (b) adding a conjugated diene-based monomer to a product of the step (a) and inducing a reaction; and (c) adding a second catalyst and a conjugated diene-based monomer to a product of the step (b) and inducing a reaction.

Provided is a method of preparing a rubber composition, which includes (a) reacting a conjugated diene-based monomer with one or more of compounds in the presence of a first catalyst; (b) adding a conjugated diene-based monomer to a product of the step (a) and inducing a reaction; and (c) adding a second catalyst and a conjugated diene-based monomer to a product of the step (b) and inducing a reaction.

Disclosed herein are mixed catalyst systems including iron-containing catalyst compounds having a carbene ligand and another catalyst compound, as well as at least one activator. The iron-containing catalyst compounds can be asymmetric, while the other catalyst compound can be symmetric. In some embodiments, the other catalyst compound can be an iron-containing catalyst with a bisiminopyridyl ligand, which does not typically incorporate comonomers in copolymer synthesis. Processes for production of an ethylene alpha-olefin copolymers using these mixed catalyst systems are also disclosed. Ethylene-alpha-olefin copolymers so formed can have at least a portion of their alpha-olefin comonomer distribution increasing with increasing molecular weight, indication orthogonal compositional distribution.

A method is described for the formation of an active catalyst system for use in the in-line bulk polymerization of polydienes. The method provides a homogeneous, active catalyst system which is capable of being transported to a polymerization reactor for use without causing blockages in piping, thereby saving time and production costs. The catalyst system is formed in-line in a continuous method to avoid prolonged storage periods of the catalyst that can otherwise lead to degradation and disposal of the aged catalyst system.

The present disclosure relates to the technical field of preparation of syndiotactic 1,2-polybutadiene (s-PB), in particular to a catalytic system and use thereof, and a preparation method of s-PB. In the present disclosure, the catalytic system includes an iron-containing organic compound, an azodicyano compound, an organoaluminum compound, and a free radical scavenger; where an iron element in the iron-containing organic compound, the azodicyano compound, the organoaluminum compound, and the free radical scavenger have a molar ratio of 1:(0.5-10):(5-100):(1-1000); and the free radical scavenger is selected from the group consisting of a sterically hindered phenol, a sterically hindered amine, and a phosphorus-containing antioxidant. The catalytic system can prepare the s-PB with a high activity at a high temperature, and the s-PB has a melting point of 60? C. to 130? C. with an extremely low gel content or even no gelation.

The present disclosure relates to the technical field of preparation of syndiotactic 1,2-polybutadiene (s-PB), in particular to a catalytic system and use thereof, and a preparation method of s-PB. In the present disclosure, the catalytic system includes an iron-containing organic compound, an azodicyano compound, an organoaluminum compound, and a free radical scavenger; where an iron element in the iron-containing organic compound, the azodicyano compound, the organoaluminum compound, and the free radical scavenger have a molar ratio of 1:(0.5-10):(5-100):(1-1000); and the free radical scavenger is selected from the group consisting of a sterically hindered phenol, a sterically hindered amine, and a phosphorus-containing antioxidant. The catalytic system can prepare the s-PB with a high activity at a high temperature, and the s-PB has a melting point of 60? C. to 130? C. with an extremely low gel content or even no gelation.