摘要:
The present application provides a catalyst for copolymerization of ethylene and methyl methacrylate and an application thereof. The catalyst includes a main catalyst, and the main catalyst is obtained by compounding a compound of formula (I) and a compound of formula (II); a mole ratio of the compound of formula (I) to the compound of formula (II) is (1:49) to (49:1). The catalyst has an excellent catalytic activity, and a copolymer of ethylene and methyl methacrylate with a high molecular weight can be obtained, with a weight average molecular weight of not less than 1×105 g/mol.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The present invention provides a polybutadiene having improved workability and abrasion resistance. A polybutadiene according to the present invention has: (A) a Mooney viscosity (ML1+4,100° C.) being 43 or more; (B) a ratio (Tcp/ML1+4,100° C.) of 5 wt % toluene solution viscosity (Tcp) to Mooney viscosity (ML1+4,100° C.) being 0.9 to 2.3; (C) a stress relaxation time (T80) being 10.0 to 40.0 seconds, which is a time until a torque is attenuated by 80% when the torque at the end of ML1+4,100° C.measurement is 100%; and (D) a molecular weight distribution (Mw/Mn) being 2.50 to 4.00.
摘要:
This invention relates to organoaluminum compounds, to organoaluminum activator systems, preferably supported, to polymerization catalyst systems containing these activator systems and to polymerization processes utilizing the same. In particular, this invention relates to catalyst systems comprising an ion-exchange layered silicate, an organoaluminum compound, and a metallocene.
摘要:
The present invention relates to a multi-component catalytic system that can be used for the cis-1,4 stereospecific polymerization of conjugated dienes. The system is based on: (i) a rare-earth complex of Formula (II) Ln(A)3(B)n, Ln being a rare-earth metal, A a ligand, B a Lewis base or a solvent molecule and n a number from 0 to 3; (ii) an alkylating agent; (iii) a compound based on an aromatic ring and having at least two heteroatoms chosen from the elements O, N, S, P, and corresponding to the Formula (III): in which the R groups each denote hydrogen, an alkyl radical optionally comprising one or more heteroatoms (N, O, P, S, Si) or one or more halogen atoms, a halogen atom, a group based on one or more heteroatoms (N, O, P, S, Si); x and y are integers from 0 to 6; D is a group having a chemical function, one of the atoms of which has a non-bonding pair; L being an atom from column 1 of the Periodic Table.
摘要:
Process for the preparation of an unsupported, heterogeneous olefin polymerization catalyst system, comprising an organometallic compound of a transition metal of Group 3 to 10 of the Periodic Table (IUPAC 2007) in the form of solid particles comprising the steps of a) preparing a solution (A) comprising ai) an organometallic compound of a transition metal of Group 3 to 10 of the Periodic Table (IUPAC 2007) or of an actinide or lanthanide, a2) a cocatalyst comprising an element of group 13 of the Periodic Table (IUPAC 2007) and a3) a solvent (A-1), b) preparing a liquid/liquid emulsion system by dispersing the solution (A) in a solvent (B) essentially immiscible with said solution (A) in the presence of a polystyrene-b-fluoro polystyrene copolymer of the formula (I) in which n is a number from 10 to 100, m is a number from 1 to 40, x is a number from 5 to 16, y is a number from 11 to 33, provided that m, n, x and y are selected in a way that the block copolymer is soluble in the solvent B or the solution A in such an extent that a stable emulsion is formed by adding the block copolymer, b1) the solvent (B) constitutes the continuous phase of the emulsion, b2) the solution (A) constitutes in the form of droplets the dispersed phase and b3) the organometallic compound and the cocatalyst are present in the droplets, c) solidifying said dispersed phase to convert said droplets to solid particles and optionally recovering said particles to obtain said catalyst system; an unsupported, heterogeneous olefin polymerization catalyst, obtainable by the process and the use of the catalyst in olefin polymerization.
摘要:
Fouling in a dispersed phase reactor in the presence of a phosphinimine catalyst and MAO may be reduced by reducing the loading of the phosphinimine catalyst to provide from 0.02 to 0.031 mmol of transition M per g of catalyst while still maintaining a productivity of not less than 2500 g of polymer/gram of catalyst. The catalyst may optionally be used in the presence of an antistatic agent.