The present disclosure relates to a method for preparing a copolymer, a copolymer prepared therefrom, and a thermoplastic resin composition including the copolymer. The method includes introducing and polymerizing an aromatic vinyl-based monomer, a vinyl cyan-based monomer, and an imide-based monomer, wherein the imide-based monomer is introduced at once in an amount of 1 wt % to 24 wt % before the start of polymerization, and is continuously introduced in an amount of 76 wt % to 99 wt % from the start of the polymerization.

The present invention provides a method for producing a porous base material having a pore with a surface modified, the method being unlikely to limit a material of the porous base material and being suitable for controlling characteristics of the porous base material by introducing a polymer chain into a surface of a pore of the porous base material while inhibiting a change in a structure of the porous base material itself. The production method of the present invention includes: forming a base layer having a polymerization initiating group in such a manner as to cover a surface of a pore of a porous base material; and allowing a monomer group to be in contact with the base layer and thereby polymerizing the monomer group by the polymerization initiating group.

Provided are a curable composition and an application thereof. The curable composition contains: a compound A having a polymerizable group (a) and an oxyfluoroalkylene group; a polymerization initiator; and a compound B having a polymerizable group different from the polymerizable group (a). The polymerizable group (a) in the compound A is at least one selected from the group consisting of a vinylphenyl group, a vinylphenyloxy group, a vinylbenzyloxy group, a vinyloxy group, a vinyloxycarbonyl group, a vinylamino group, a vinylaminocarbonyl group, a vinylthio group, an allyloxy group, an allyloxycarbonyl group, an allylamino group, an allylaminocarbonyl group, an allylthio group, an epoxy group, and an epoxycycloalkyl group.

The present invention provides a process for the preparation of a multimodal polyethylene comprising: (i) polymerising ethylene and optionally an α-olefin comonomer in a first polymerisation stage to produce a first ethylene polymer; and (ii) polymerising ethylene and optionally an α-olefin comonomer, in the presence of said first ethylene polymer, in a second polymerisation stage, wherein the first and second polymerisation stages are carried out in the presence of an unsupported metallocene catalyst and each polymerisation stage produces at least 5% wt of the multimodal polyethylene, and the multimodal polyethylene has a multimodal molecular weight distribution, a molecular weight of at least 50,000 g/mol and a bulk density of at least 250 g/dm.sup.3, and wherein a solution of the unsupported metallocene catalyst in a solvent is employed. The present invention also provides a multimodal polyethylene, a process for preparing a pipe comprising preparing a multimodal polyethylene and extruding the multimodal recycle polyethylene to produce a pipe, and a pipe obtained by such a process.

Scavenging chemicals used in mitigation treatments of hydrogen sulfide in hydrocarbon streams often continue to react and form polymers that foul the processing system. Disclosed herein are methods for determining if a scavenging chemical mitigator, or its reaction or degradation product, will polymerized during or after mitigation treatments. This information allows for the optimization of mitigation treatments that pre-emptively control or prevent polymer formation. Such pre-emption measures reduce the cost and time related to remedial actions to treat polymer-fouled equipment.

Scavenging chemicals used in mitigation treatments of hydrogen sulfide in hydrocarbon streams often continue to react and form polymers that foul the processing system. Disclosed herein are methods for determining if a scavenging chemical mitigator, or its reaction or degradation product, will polymerized during or after mitigation treatments. This information allows for the optimization of mitigation treatments that pre-emptively control or prevent polymer formation. Such pre-emption measures reduce the cost and time related to remedial actions to treat polymer-fouled equipment.

The present invention relates to a superabsorbent polymer showing a low degree of decrease in absorption capacity, and a preparation method thereof. Specifically, the present invention provides a superabsorbent polymer having an excellent rewetting prevention ability such that moisture hardly leaks out under pressure even after a certain time, and a preparation method thereof, by preparing an acrylic resin with a high molecular weight main chain that is evenly cross-linked for maintaining high gel strength by minimizing an amount of an initiator with respect to a monomer.

The present invention relates to a superabsorbent polymer showing a low degree of decrease in absorption capacity, and a preparation method thereof. Specifically, the present invention provides a superabsorbent polymer having an excellent rewetting prevention ability such that moisture hardly leaks out under pressure even after a certain time, and a preparation method thereof, by preparing an acrylic resin with a high molecular weight main chain that is evenly cross-linked for maintaining high gel strength by minimizing an amount of an initiator with respect to a monomer.

Propylene is polymerised in the presence of a polymerisation catalyst comprising a solid catalyst component, an organoaluminium compound and an external electron donor, the process comprising the steps of (i) contacting propylene and hydrogen with the polymerisation catalyst in polymerisation conditions in a polymerisation reactor to produce a polymer of propylene; (ii) recovering the polymer of propylene from the polymerisation reactor; wherein the polymer of propylene has MFR of from more than 100 to 10000 g/10 min. The solid catalyst component comprises titanium, magnesium, halogen and an internal electron donor, characterised in that the internal electron donor is a compound according to formula (I) with R.sub.1 and R.sub.2 being the same or different and being a linear or branched C.sub.1-C.sub.12-alkyl group, and with R being H or a linear, branched or cyclic C.sub.1 to C.sub.12-alkyl, whereby it is preferred that R is not H. The external electron donor is a silane compound having the formula Si(OR.sup.11).sub.nR.sup.10.sub.4-n, wherein each R.sup.10 is independently a linear or branched C.sub.1-C.sub.4 alkyl, preferably methyl or ethyl; and each R.sup.10 is independently a linear or branched alkyl group having from 1 to 24 and optionally containing an atom of group 15 of periodic table of elements or comprises a cyclic group having from 6 to 12 carbon atoms.

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The present application relates to a process for producing a multimodal polyethylene composition comprising the steps of polymerizing a polyethylene fraction (A-1) having a weight average molecular weight Mw of equal to or more than 500 kg/mol to equal to or less than 10,000 kg/mol and a density of equal to or more than 915 kg/m.sup.3 to equal to or less than 960 kg/m.sup.3 in one reaction step and polymerizing a polyethylene fraction (A-2) having a lower weight average molecular weight Mw as polyethylene fraction (A-1) and a density of equal to or more than 910 kg/m.sup.3 to equal to or less than 975 kg/m.sup.3 in a second reaction step of a sequential multistage process wherein one of said polyethylene fractions is polymerized in the presence of the other of said polyethylene fractions to form a first polyethylene resin (A) having a weight average molecular weight Mw of equal to or more than 150 kg/mol to equal to or less than 1,500 kg/mol, and a density of equal to or more than 910 kg/m.sup.3 to equal to or less than 975 kg/m.sup.3, wherein the weight average molecular weight Mw of the first polyethylene resin (A) is lower than the weight average molecular weight Mw of the polyethylene fraction (A-1), blending the first polyethylene resin (A) with a second polyethylene resin (B) having a weight average molecular weight Mw of equal to or more than 50 kg/mol to less than 500 kg/mol, and a density of equal to or more than 910 kg/m.sup.3 to equal to or less than 970 kg/m.sup.3 to form said multimodal polyethylene composition, wherein the multimodal polyethylene composition a melt flow rate MFR.sub.5 (190° C., 5 kg) of 0.01 to 10 g/10 min and a density of equal to or more than 910 kg/m.sup.3 to equal to or less than 970 kg/m.sup.3 a polyethylene composition obtainable by said process and the polyethylene resin of said first polymerization step.