摘要:
A process for preparing a polydiene, the process comprising the step of polymerizing conjugated diene monomer with a nickel-based catalyst system, where said step of polymerizing takes place within a polymerization mixture that includes less than 20% by weight of organic solvent based on the total weight of the polymerization mixture, where the temperature of the polymerization mixture is maintained below 34° C. during said step of polymerizing, and where the conversion of the conjugated diene monomer is maintained below 30%.
摘要:
Process for production of post-crosslinkable thermoplastic resins by bulk-polymerizing a polymerizable composition (A) comprising (I) a monomer fluid containing a cyclic olefin (α) having two or more metathetical ring-opening reaction sites in the molecule in an amount 10 wt % or above based on the total amount of the monomers or a monomer fluid containing a norbornene monomer and a crosslinking agent, (II) a metathetical polymerization catalyst, and (III) a chain transfer agent; thermoplastic resins obtained by this process. These thermoplastic resins are free from odor due to residual monomers and are excellent in storage stability. Process for producing crosslinked resins and composite materials which comprises laminating the thermoplastic resin to a substrate and then crosslinking the thermoplastic resin. These crosslinked resins and composite materials are invention are excellent in electrical insulation properties, mechanical strength, heat resistance, and dielectric characteristics, and are useful as electrical materials.
摘要:
A method for the continuous production of polydienes, the method comprising the steps of (a) charging a mixture of one or more monomer, catalyst system, and less than 50% weight percent organic solvent based on the total weight of the monomer, catalyst and solvent, into first vessel, (b) polymerizing the monomer to a conversion of up to 20% by weight of the monomer to form a mixture of reactive polymer and monomer, (c) removing the mixture of reactive polymer and monomer from the vessel, and (d) terminating the reactive polymer prior to a total monomer conversion of 25% by weight.
摘要:
A synthesis process of trans-1,4-polyisoprene, using bulk precipitation polymerization of isoprene catalyzed by supported titanium catalyst TiCl4/MgCl2. The process includes prepolymerizing carried out in a prepolymerization reactor with an anchor agitator; polymerizing carried out in a polymerization reactor with a helical ribbon agitator; and devolatilizing and drying carried out in a vacuum rake dryer. Not only does the process require lower energy consumption and thus a lower production cost, but it also eliminates the emission of three wastes.
摘要:
Provided are bulk homogeneous polymerization processes for producing ethylene propylene random copolymers. The process includes contacting in a reactor or in a series of reactors propylene monomer, ethylene comonomer with one or more catalyst systems and optional solvent (present at less than 40 wt %), wherein the reactor train is at a temperature of between 65° C. and 180° C. and at a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system and less than 1500 MPa, and wherein the polymerization system for the reactor train is in its dense fluid state to form a polymer reactor effluent including a homogeneous fluid phase polymer-monomer mixture in the reactor train; and wherein the resultant copolymer product comprises between 10 wt % and 20 wt % randomly distributed ethylene and the concentration of total region defects in the continuous propylene segments of the random EP copolymer is between 40 and 150% greater than in a copolymer of equivalent melt flow rate and wt % ethylene polymerized by a solution polymerization process.
摘要:
The present invention relates to a process for preparing an activating support for metallocene complexes in the polymerisation of olefins comprising the steps of: I) providing a support prepared consisting in particles formed from at least one porous mineral oxide; II) optionally fixing the rate of silanols on the surface of the support; III) functionalising the support with a solution containing a fluorinated functionalising agent; IV) heating the functionalised and fluorinated support of step c) under an inert gas and then under oxygen; V) retrieving an active fluorinated support. That activating support is used to activate a metallocene catalyst component for the polymerisation of olefins.
摘要:
The invention relates to a process for the production of post-crosslinkable thermoplastic resins by bulk-polymerizing a polymerizable composition (A) comprising (I) a monomer fluid containing a cyclic olefin (α) having two or more metathetical ring-opening reaction sites in the molecule in an amount 10 wt % or above based on the total amount of the monomers or a monomer fluid containing a norbornene monomer and a crosslinking agent, (II) a metathetical polymerization catalyst, and (III) a chain transfer agent; thermoplastic resins obtained by this process; and a process for producing crosslinked resins or crosslinked resin composite materials which comprises laminating such a thermoplastic resin with a substrate at need and then crosslinking the thermoplastic resin. According to the invention, thermoplastic resins which are free from odor due to residual monomers and excellent in storage stability can be efficiently obtained by a simple process of bulk-polymerizing the composition (A). The process is not only easy and simple but also applicable to continuous production, thus being industrially advantageous. The crosslinked resins and crosslinked resin composite materials obtained according to the invention are excellent in electrical insulation properties, mechanical strengths, heat resistance, dielectric characteristics and so on, thus being useful as electrical materials or the like.
摘要:
The present invention relates to a supported catalyst composition and a method for making the supported catalyst composition and its use in a process for polymerizing olefin(s). In particular, the invention is directed to a method for making a supported catalyst composition by contacting a supported activator with a bulky ligand and a metal compound.
摘要:
There is provided a synthetic resin emulsion comprising polymer particles having a core/shell structure, wherein the shell comprises a copolymer of an unsaturated carboxylic acid and a hydrophilic comonomer, the core comprises a copolymer of a monomer mixture comprising a radically polymerizable main monomer and a radically polymerizable functional monomer, and the monomers constituting the monomer mixture are selected so that the glass transition point (Tg) of the copolymer produced by polymerization is −20° C. or below, and the synthetic resin emulsion has been produced by adding the monomer mixture for core formation and a pH adjustor to an aqueous copolymer solution, which has not been neutralized, produced by polymerizing the unsaturated carboxylic acid and the hydrophilic comonomer in an aqueous medium, and allowing a polymerization reaction to proceed. The use of the synthetic resin emulsion can provide a pressure-sensitive adhesive which has excellent adhesive properties such as adhesive strength, cohesive force and tackiness and can be easily swollen with water without any treatment with an alkali.
摘要:
The present invention relates to a fiber coated with a water blocking material that includes an essentially water free dispersion comprising a superabsorbent polymer and a dispersing medium. The fibers made according to this invention may be used, for example, as fiber reinforcing material used in the manufacture of cables, and in particular in yarns for fiber optical cables that use optical light wave guides for optical communication transmissions.