A method can be used for manufacturing an ethylene-propylene-diene terpolymer for a fuel cell. A polymerization step includes subjecting an organic chelate compound forming a coordinate bond, a vanadium-based Ziegler-Natta catalyst, an organoaluminum compound, and ethylene, propylene, and diene monomers, together with a solvent, to polymerization in a reactor. A separation step includes recovering residual catalysts and unreacted monomers from the stream discharged from the reactor. An acquisition step includes recovering the solvent from the stream deprived of the residual catalysts and unreacted monomers to acquire the ethylene-propylene-diene terpolymer.

A method can be used for manufacturing an ethylene-propylene-diene terpolymer for a fuel cell. A polymerization step includes subjecting an organic chelate compound forming a coordinate bond, a vanadium-based Ziegler-Natta catalyst, an organoaluminum compound, and ethylene, propylene, and diene monomers, together with a solvent, to polymerization in a reactor. A separation step includes recovering residual catalysts and unreacted monomers from the stream discharged from the reactor. An acquisition step includes recovering the solvent from the stream deprived of the residual catalysts and unreacted monomers to acquire the ethylene-propylene-diene terpolymer.

A tackifier (B) according to the present invention comprises a copolymer (C) that comprises a structural unit derived from α-methylstyrene or isopropenyltoluene and a structural unit derived from styrene, and the copolymer (C) satisfies the following (i) to (iii): (i) a content of the structural unit derived from α-methylstyrene or isopropenyltoluene is in the range of 30 to 70 mol %, (ii) a softening temperature (Tm) measured by the ring-and-ball method according to JIS K 2207 is in the range of 110° C. to 170° C., and (iii) a content of a fraction having molecular weight of not more than 350, as determine by gel permeation chromatography (GPC) and calculated from polystyrene standard, is less than 1.5 mass %.

A tackifier (B) according to the present invention comprises a copolymer (C) that comprises a structural unit derived from α-methylstyrene or isopropenyltoluene and a structural unit derived from styrene, and the copolymer (C) satisfies the following (i) to (iii): (i) a content of the structural unit derived from α-methylstyrene or isopropenyltoluene is in the range of 30 to 70 mol %, (ii) a softening temperature (Tm) measured by the ring-and-ball method according to JIS K 2207 is in the range of 110° C. to 170° C., and (iii) a content of a fraction having molecular weight of not more than 350, as determine by gel permeation chromatography (GPC) and calculated from polystyrene standard, is less than 1.5 mass %.

A process for the offline deactivation of at least one single site catalyst comprising contacting said catalyst with a deactivating agent selected from an aprotic low molecular weight carbonyl group containing organic compound or an aprotic low molecular weight orthoester or an aprotic low molecular weight acetal compound.

A process for the offline deactivation of at least one single site catalyst comprising contacting said catalyst with a deactivating agent selected from an aprotic low molecular weight carbonyl group containing organic compound or an aprotic low molecular weight orthoester or an aprotic low molecular weight acetal compound.

Processes and apparatus for preparing bimodal polymers are provided. In some embodiments, processes include introducing a monomer, a first diluent, a catalyst, hydrogen, at a first hydrogen concentration, and optional comonomer, to a first loop reactor to produce, under polymerization conditions, a first slurry of polymer solids. Processes may also include continuously discharging the first slurry of polymer solids from the loop reactor as a first polymerization effluent to a first flash tank; separating the first polymerization effluent in the first flash tank to provide a first concentrated polymer slurry with significantly lower hydrogen concentration; and transferring the first concentrated polymer slurry from the flash tank to a re-slurry mixer. Processes may further include introducing a re-slurry mixer diluent to the first concentrated polymer slurry to form a second concentrated polymer slurry in the re-slurry mixer that can be pumped to a second slurry loop reactor.

Processes and apparatus for preparing bimodal polymers are provided. In some embodiments, processes include introducing a monomer, a first diluent, a catalyst, hydrogen, at a first hydrogen concentration, and optional comonomer, to a first loop reactor to produce, under polymerization conditions, a first slurry of polymer solids. Processes may also include continuously discharging the first slurry of polymer solids from the loop reactor as a first polymerization effluent to a first flash tank; separating the first polymerization effluent in the first flash tank to provide a first concentrated polymer slurry with significantly lower hydrogen concentration; and transferring the first concentrated polymer slurry from the flash tank to a re-slurry mixer. Processes may further include introducing a re-slurry mixer diluent to the first concentrated polymer slurry to form a second concentrated polymer slurry in the re-slurry mixer that can be pumped to a second slurry loop reactor.

The present invention relates to a method of preparing an aqueous dispersion of multistage polymer particles comprising contacting under emulsion polymerization conditions and in a staged fashion an aqueous dispersion of carboxylic acid functionalized core polymer particles with first monomers and second monomers. The core comprises structural units of a high T.sub.g hydrophobic monomer and/or the first monomers comprise a high T.sub.g hydrophobic monomer, and the second monomers comprise at least 80 percent styrene. The high T.sub.g hydrophobic monomer is cyclohexyl methacrylate, isobornyl methacrylate, 4-t-butyl methacrylate, t-butylstyrene, or n-butyl methacrylate, or a combination thereof. The multistage polymer particles are useful as opaque polymers, which are used in pigmented coating formulations to reduce the load of TiO.sub.2. The particles exhibit excellent collapse resistance and unusually low dry bulk density, and do not require acrylonitrile to achieve this desired combination of properties.

The present invention relates to a method of preparing an aqueous dispersion of multistage polymer particles comprising contacting under emulsion polymerization conditions and in a staged fashion an aqueous dispersion of carboxylic acid functionalized core polymer particles with first monomers and second monomers. The core comprises structural units of a high T.sub.g hydrophobic monomer and/or the first monomers comprise a high T.sub.g hydrophobic monomer, and the second monomers comprise at least 80 percent styrene. The high T.sub.g hydrophobic monomer is cyclohexyl methacrylate, isobornyl methacrylate, 4-t-butyl methacrylate, t-butylstyrene, or n-butyl methacrylate, or a combination thereof. The multistage polymer particles are useful as opaque polymers, which are used in pigmented coating formulations to reduce the load of TiO.sub.2. The particles exhibit excellent collapse resistance and unusually low dry bulk density, and do not require acrylonitrile to achieve this desired combination of properties.