The present invention relates to a copolymer including 20 to 65 wt % of units derived from an alkyl styrene-based monomer; 10 to 40 wt % of units derived from a (meth)acrylate-based monomer; and 20 to 40 wt % of units derived from vinyl cyan-based monomer, based on the total weight of the copolymer, wherein the residual monomer content is 780 ppm or less, and a method for preparing the same.

A fluororesin including a vinylidene fluoride unit and a tetrafluoroethylene unit. The fluororesin has a gas chromatography-mass spectrometry total ion chromatogram including a peak which is assigned to a component having a molecular weight of 202 to 903 and which has a peak intensity of 1000 or lower. Also disclosed is a molded article formed from the fluororesin.

A fluororesin including a vinylidene fluoride unit and a tetrafluoroethylene unit. The fluororesin has a gas chromatography-mass spectrometry total ion chromatogram including a peak which is assigned to a component having a molecular weight of 202 to 903 and which has a peak intensity of 1000 or lower. Also disclosed is a molded article formed from the fluororesin.

The invention relates to a process for removal of volatile components from an olefin polymer, the process carried out in an extruder comprising at least one vacuum degassing zone, said process comprising the steps of: (a) introducing a stream of an olefin polymer into the extruder; (b) extruding the olefin polymer in the extruder at a temperature which is higher than the melting temperature of the olefin polymer but lower than the decomposition temperature of the olefin polymer, thereby producing an olefin polymer melt having reduced amount of volatile components, wherein the process in the extruder has a residence time distribution broadness (σ2) in the range of 800 to 4000 as define by equation (1) wherein: σ2 is the residence time distribution broadness, T is the mean residence time, t is the interval of residence time a fluid element of the olefin polymer spends in the extruder, E(t) is the residence time distribution function, and wherein the process optionally comprises a step (c) where the melt of the olefin polymer is passed through a die zone to a pelletizer for pelletizing the obtained olefin polymer.
σ.sup.2=∫.sub.0.sup.∞(t−τ).sup.2E(t)dt  equation (1)

The invention relates to a process for removal of volatile components from an olefin polymer, the process carried out in an extruder comprising at least one vacuum degassing zone, said process comprising the steps of: (a) introducing a stream of an olefin polymer into the extruder; (b) extruding the olefin polymer in the extruder at a temperature which is higher than the melting temperature of the olefin polymer but lower than the decomposition temperature of the olefin polymer, thereby producing an olefin polymer melt having reduced amount of volatile components, wherein the process in the extruder has a residence time distribution broadness (σ2) in the range of 800 to 4000 as define by equation (1) wherein: σ2 is the residence time distribution broadness, T is the mean residence time, t is the interval of residence time a fluid element of the olefin polymer spends in the extruder, E(t) is the residence time distribution function, and wherein the process optionally comprises a step (c) where the melt of the olefin polymer is passed through a die zone to a pelletizer for pelletizing the obtained olefin polymer.
σ.sup.2=∫.sub.0.sup.∞(t−τ).sup.2E(t)dt  equation (1)

A method of producing advanced carbon materials can include providing coal to a processing facility, beneficiating the coal to remove impurities from the coal, processing the beneficiated coal to produce a pitch, and treating the pitch to produce an advanced carbon material such as carbon fibers, carbon nanotubes, graphene, carbon fibers, polymers, biomaterials, or other carbon materials.

A method of producing advanced carbon materials can include providing coal to a processing facility, beneficiating the coal to remove impurities from the coal, processing the beneficiated coal to produce a pitch, and treating the pitch to produce an advanced carbon material such as carbon fibers, carbon nanotubes, graphene, carbon fibers, polymers, biomaterials, or other carbon materials.

Provided are a polymer having ultraviolet absorption functionality and preparation method thereof; specifically, three monomers having different ultraviolet absorption bands are used for copolymerization, achieving a significant expansion of the ultraviolet absorption range and achieving the effect of full-band ultraviolet shielding. The obtained polymer film has strong visible light transmittance, fluorescence, easy processing, excellent stability, and remarkable ultraviolet shielding performance, and can be broadly applied in such areas as aviation, construction, agriculture, and optical devices.

Provided are a polymer having ultraviolet absorption functionality and preparation method thereof; specifically, three monomers having different ultraviolet absorption bands are used for copolymerization, achieving a significant expansion of the ultraviolet absorption range and achieving the effect of full-band ultraviolet shielding. The obtained polymer film has strong visible light transmittance, fluorescence, easy processing, excellent stability, and remarkable ultraviolet shielding performance, and can be broadly applied in such areas as aviation, construction, agriculture, and optical devices.

Provided by the present invention is a production method of a polyvinyl alcohol resin in which a content of organic volatiles has been reduced while inhibiting fusing of the resin to itself. The production method includes a step of washing, with a washing liquid, a polyvinyl alcohol obtained by saponifying a polyvinyl ester, wherein the washing liquid contains 50 to 98 parts by mass of methyl acetate, 1 to 49 parts by mass of methanol, and 1 to 10 parts by mass of water with respect to 100 parts by mass being a total of methyl acetate, methanol, and water.