Methods of vulcanization using a high content sulfur polymer, instead of elemental sulfur, have been developed. These high sulfur content polymers are referred to as Chalcogenide Hybrid Inorganic/Organic Polymers (CHIP) materials and have good polymer compatibility in that they are soluble in a number of polymers. Furthermore, CHIP materials may have weaker bonds than the S—S bonds of elemental sulfur and thus provide for a higher crosslinking efficiency vulcanization.

A method for preparing polyarylene sulfide that can control a viscosity grade thereof by adjusting the molar ratio of water and amide-based compounds present in a polymerization reaction.

A method for preparing polyarylene sulfide that can control a viscosity grade thereof by adjusting the molar ratio of water and amide-based compounds present in a polymerization reaction.

A triazine ring-containing polymer including a repeating unit represented by Formula (1) and having a number average molecular weight of greater than about 20000 g/mol and less than or equal to about 50000 g/mol: ##STR00001## wherein, in Formula (1), R.sup.1 is each independently a C1 to C5 alkyl group and R.sup.2 is each independently a divalent group having at least one aromatic hydrocarbon group.

The polymerizable composition of the present application may exhibit a wide process window to have excellent workability, and may form a phthalonitrile resin having excellent heat resistance or a prepolymer thereof.

The polymerizable composition of the present application may exhibit a wide process window to have excellent workability, and may form a phthalonitrile resin having excellent heat resistance or a prepolymer thereof.

A triazine ring-containing polymer having a high refractive index and a low birefringence, and being capable of being subjected to injection molding, wherein the polymer having a repeating unit of *-[A-B-]-*, including a structural unit A derived from a triazinedithiol compound, and a structural unit B including an aromatic hydrocarbon group; and a thermoplastic resin, a thermoplastic article, and an optical part including the polymer.

A curable composition for forming a high refractive index optical material including an episulfide compound, a cyclic disulfide compound, and a reducing agent, and an optical material comprising a cured product of the curable composition.

A curable composition for forming a high refractive index optical material including an episulfide compound, a cyclic disulfide compound, and a reducing agent, and an optical material comprising a cured product of the curable composition.

The present application relates to a phthalonitrile resin and the like. The present application can provide a phthalonitrile resin, and a polymerizable composition and prepolymer using the same, which can exhibit excellent curability, a suitable processing temperature and a wide process window, and form a composite having excellent physical properties. Also, according to the present invention, there may be provided a phthalonitrile resin, and a polymerizable composition and prepolymer using the same, which can exhibit appropriate viscosity characteristics and thus provide a final product without deterioration of mechanical physical properties or the like due to bubbles generated during processing.