摘要:
A radical-modified polymer having a free radical compound stable in the presence of oxygen at an ordinary temperature at the end of the molecule thereof or in the molecular chain thereof and a polymer composition containing the same.
摘要:
The invention discloses a method for preparing a tri block copolymer of the formula: comprising: (a) contacting a cycloalkene with a chain transfer agent of the formula: Z—Y═Y—Z in the presence of a metal carbene metathesis catalyst to form a telechelic polymer; and (d) contacting the telechelic polymer with an alkene of the formula in the presence of an ATRP organometallic catalyst wherein n and m are integers; Z is an ATRP initiator and —Y═Y— is an alkenyl group; and, R′ is selected from the group consisting of aryl, nitrile and C1-C20 carboxylate, wherein R′ is substituted or unsubstituted. The invention also discloses a method for preparing a diblock copolymer. In addition, the invention encompasses a triblock copolymer having no 1,2-PBD structure in the PBD portion of the copolymer.
摘要:
The present invention relates to a cycloolefin polymer having a solution viscosity >0.25 dl/g and containing polymerized units of at least one cycloolefin and, if desired, polymerized units of one or more acyclic olefins, wherein the cycloolefin polymer has at one or both ends an olefinically unsaturated group having at least 3 carbon atoms.
摘要:
Multistage process for the polymerization of olefins CH.sub.2 .dbd.CHR, where R is hydrogen or an alkyl, cycloalkyl or aryl radical with 1-10 carbon atoms, comprising two stages of polymerization. In a first stage, in the presence of a titanium or a vanadium catalyst and working in one or more reactors, an olefinic polymer with particular values of porosity is prepared; in a second stage, in the presence of the said porous polymer and a metallocene compound and/or their reaction products, one or more olefins, that are equal to or different from those polymerized in the first stage, are polymerized in one or more reactors.
摘要:
A conjugated diene compound prepolymer solution useful for the production of a vinyl aromatic compound high impact polymer material is produced by a process in which a prepolymerization mixture is prepared from 1 to 70 parts by weight of a conjugated diene compound and 30 to 99 parts by weight of a vinyl aromatic compound, and is prepolymerized at 0.degree. C. to 150.degree. C. in the presence of a prepolymerization catalyst which can cause the conjugated diene compound to be selectively polymerized but is substantially not effective for the polymerization of the vinyl aromatic compound to an extent such that the conjugated diene compound and the vinyl aromatic compound are prepolymerized at degrees of conversion of the conjugated diene compound at least 50% and 10% or less, respectively, and the resultant prepolymer solution is further polymerized by a radical or anionic polymerization method so that the vinyl aromatic compound is polymerized with the conjugated diene compound prepolymer.
摘要:
A polybutadiene rubber having an enhanced mechanical strength is produced in such a manner that the content of water in a solution of 1,3-butadiene in an inert organic solvent is controlled to 0.2 to 5 millemoles per liter of 1,3-butadiene; a first polymerization mixture is prepared from the controlled 1,3-butadiene solution, an organic aluminum compound of the formula Al R.sub.n X.sub.3-n, wherein R=C.sub.1-6 alkyl, phenyl, or cycloalkyl, X=halogen, and n=1.5-2.0, and a cobalt compound, for example, by aging a mixture of the controlled 1,3-butadiene solution with the aluminum compound for at least one minute and then by admixing the aged mixture with the cobalt compound; the first polymerization mixture is subjected to a cis-1,4-polymerization; a second polymerization comprising the resultant cis-1,4-polybutadiene, non-reacted 1,3-butadiene, the inert organic solvent, and a catalyst comprising an organic aluminum compound of the formula AlR.sub.3, a cobalt compound, and carbon disulfide is subjected to a 1,2-polymerization to produce a polybutadiene rubber consisting essentially of 5% to 30% by weight of a boiling n-hexane-insoluble fraction and 70% to 95% by weight of a boiling n-hexane-soluble fraction thereof and having an excellent mechanical strength; and after the 1,2-polymerization is shortstopped, the resultant polybutadiene rubber is isolated from the 1,2-polymerization mixture.
摘要:
Block copolymers are produced by (i) polymerizing ethylene or propylene, or copolymerizing the same with another .alpha.-olefin of 2 to 7 carbon atoms in the presence of a Ziegler-type catalyst, and (ii) copolymerizing the resulting polymer or copolymer with a radical-polymerizable vinyl compound (e.g., methyl methacrylate) in the presence of an organic sulfoxide.
摘要:
Concentrates containing specific functionalized diblock copolymers serve as effective additives for improving the cold flow behavior of fuels and oils, the copolymers being derived from a terminally-unsaturated intermediate polymer obtained via a metallocene process involving hydrogen.
摘要:
Stereoregular diblock polybutadiene composed of a polybutadiene block having a 1,4-cis structure and a polybutadiene block having a syndiotactic 1,2 structure. Said stereoregular diblock polybutadiene can be advantageously used in both the footwear industry (for example, in the production of soles for shoes) and in the production of tires for motor vehicles and/or trucks.
摘要:
To provide a novel cross copolymer and resin composition which are improved in heat resistance and compatibility over conventional ethylene/aromatic vinyl compound copolymers and which have low crystallinity, are excellent in softness, transparency and compatibility and show mechanical properties similar to soft vinyl chloride resins, as compared with conventional cross copolymers.A process for producing a cross copolymer, which comprises a coordination polymerization step and a subsequent anionic polymerization step, wherein in the coordination polymerization step, copolymerization of an olefin monomer, an aromatic vinyl compound monomer and an aromatic polyene is carried out by using a single-site coordination polymerization catalyst to synthesize an olefin/aromatic vinyl compound/aromatic polyene copolymer, and then, in the anionic polymerization step, polymerization is carried out in the coexistence of such an olefin/aromatic vinyl compound/aromatic polyene copolymer and an anionic polymerizable vinyl compound monomer by using an anionic polymerization initiator.