A crosslinked rubber is produced by crosslinking a polymer composition containing 100 parts by weight of a rubber component containing a cyclopentene ring-opening polymer and 20 to 200 parts by weight of carbon black, wherein, when the crosslinked rubber is subjected to an ozone treatment in which the rubber is maintained at 40° C. and an ozone concentration of 50 pphm for 144 hours under a 20% tensile strain, the crosslinked rubber shows a rate of change in tensile strength before and after ozone treatment of within ±70%.

Nitrogen heterocyclic carbine ligands and ruthenium catalysts thereof, a preparation method therefor and an application thereof are provided. The structures of the nitrogen heterocyclic carbine ligands are represented by formulas Ia and Ib, respectively, and the corresponding ruthenium catalyst structures are represented by IIa and IIb, respectively. After simultaneously introducing large-steric hindrance and electron-rich groups into the described nitrogen heterocyclic carbine ligand structures, the catalytic activity, stability and application range of the ruthenium complex catalysts thereof are significantly improved.

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The present disclosure provides compositions and methods for metathesizing a first alkenyl or alkynyl group with a second alkenyl or alkynyl group, the composition comprising a ruthenium metathesis catalyst and a photo-redox catalyst that is activated by infrared light.

A prepolymer is prepared by subjecting a compound of Formula (I) and a vinyl-containing compound to a prepolymerization reaction, and a resin composition includes the prepolymer. The vinyl-containing compound includes bis(vinylphenyl) ethane, divinylbenzene, modification of divinylbenzene or a combination thereof. A ratio in part by weight of the compound of Formula (I) to the vinyl-containing compound in the prepolymerization reaction is 8:2 to 6:4. The resin composition includes the prepolymer and an additive, and an article made from the resin composition may include a resin film, a prepreg, a laminate or a printed circuit board.

A rubber composition that contains 0.1 to 50 parts by weight of an organic peroxide with respect to 100 parts by weight of a cyclopentene ring-opening polymer.

A supported catalyst system is based on a transition metal carbene including the moiety M1=CR*).sub.2, wherein M.sup.1 is the transition metal and R* is hydrogen or a C.sub.1-C.sub.8 hydrocarbyl. The catalyst system can be supported on a metal oxide support such as silica or the catalyst can be self-supporting. Methods of making the catalyst system can involve precursors based on and/or reacted with aluminum alkyls, halides, and/or alkoxides. Methods of polymerizing cyclic olefins with the catalyst system can obtain polyalkenamers, cyclic olefin polymers, cyclic olefin copolymers, and other metathesis reaction products. The supported catalyst and/or monomer can be recovered and recycled to the polymerization reactor.

Described herein are compositions and methods for processing photopolymers based on olefin metathesis. The compositions and methods comprise latent ruthenium complexes and photoacids and/or photoacid generators.

A ring-opened copolymer composition has a ring-opened copolymer containing structural unit derived from a norbornene compound represented by general formula (1) below and structural unit derived from a monocyclic olefin, wherein a content of a norbornene compound represented by general formula (1) is 1 ppm by weight or more and 1000 ppm by weight or less based on the ring-opened copolymer, ##STR00001## wherein R.sup.1 to R.sup.4 are each a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a substituent containing a halogen atom, a silicon atom, an oxygen atom or a nitrogen atom, and R.sup.2 and R.sup.3 may be bonded to each other to form a ring, and “m” is 0 or 1.

The present application is directed to a nanocomposite organo gel having a continuous polymeric network structure, wherein polymer chains are held together by ionic interaction between polymer chain ends, interparticle chain entanglements, layered silicate surface modifier, ionic salt, and layered silicate. The present application is also directed to methods of making and using the nanocomposite organo gel.

A method of forming polymeric proppants in-situ during a fracturing operation. The method includes the steps of delivering reagents downhole and combining the reagents in a first mixing chamber to initiate polymerization; atomizing the combined reagents by passing them through an atomizer as they exit the first mixing chamber to form partially polymerized polymeric bodies; pumping water down a production casing; mixing the partially polymerized polymeric bodies and the water in a second mixing chamber; completing polymerization and forming solid polymeric proppants upon exiting the second mixing chamber; and passing the solid polymeric proppants through perforations in the casing and into fractures within the formation. A system for forming polymeric proppants in-situ during a fracturing operation and a method for forming solid polymeric proppants at the surface of a formation for use in a fracturing operation is also provided.