A copolymer has low levels of cyclic oligomeric compounds, which are undesirable impurities in certain applications. The cyclic oligomeric compounds are provided in an advantageously low ratio of C21/C13 oligomers. The C13 oligomers are extractable using steam to further reduce the total amount of cyclic oligomers. A process for producing the copolymer having low levels of cyclic oligomers involves contacting at least one isoolefin monomer with at least one multiolefin and/or -pinene monomer in the presence of at least one Lewis acid and at least one initiator in a diluent. The diluent contains a hydrofluorinated olefin (HFO) comprising at least three carbon atoms and at least three fluorine atoms. Hydrofluorinated olefins used in the present invention are better diluents for butyl slurry cationic polymerization than saturated hydrofluorocarbons.

Process for polymerizing monomer in a reactor by withdrawing an effluent from the reactor which is a slurry of polymer solids in a liquid medium and contacting a first stream containing vapor derived from the effluent withdrawn from the reactor with a feed stream to the reactor. The first stream which has the majority of the vaporized components of the liquid medium in the effluent withdrawn from the reactor is brought into contact with the feedstream to the reactor at a pressure of 0.5 MPa or above and/or the first stream is separated from the polymer withdrawn from the reactor at a pressure of 0.5 MPa or above.

A fluororesin including a residue unit of formula (1) and having a haze value equal to 2% or less of a heat-press molded product (thickness 1 mm) with a small haze value of a melt-molded product and a method for producing the same. ##STR00001##
Rf.sub.1, Rf.sub.2, Rf.sub.3 and Rf.sub.4 each independently represent one of the groups consisting of a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, and a cyclic perfluoroalkyl group having 3 to 7 carbon atoms, the perfluoroalkyl group may have an ethereal oxygen atom, Rf.sub.1, Rf.sub.2, Rf.sub.3 and Rf.sub.4 may be linked to each other to form a ring having 4 or more and 8 or less carbon atoms, and the ring may include an ethereal oxygen atom.

A fluororesin including a residue unit of formula (1) and having a haze value equal to 2% or less of a heat-press molded product (thickness 1 mm) with a small haze value of a melt-molded product and a method for producing the same. ##STR00001##
Rf.sub.1, Rf.sub.2, Rf.sub.3 and Rf.sub.4 each independently represent one of the groups consisting of a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, and a cyclic perfluoroalkyl group having 3 to 7 carbon atoms, the perfluoroalkyl group may have an ethereal oxygen atom, Rf.sub.1, Rf.sub.2, Rf.sub.3 and Rf.sub.4 may be linked to each other to form a ring having 4 or more and 8 or less carbon atoms, and the ring may include an ethereal oxygen atom.

A process for preparing an ethylene polymer in a suspension polymerization including the steps of separating the formed suspension of ethylene polymer particles in a solid-liquid separator into ethylene polymer particles and mother liquor, transferring a first part of the mother liquor into a work-up section including an evaporation unit for producing a wax-depleted portion of the mother liquor, wherein a protic agent is added to the part of the mother liquor which is transferred into the work-up section, and recycling a first part of the wax-depleted portion of the mother liquor to the polymerization reactor or the series of polymerization reactors.

A process for preparing an ethylene polymer in a suspension polymerization including the steps of separating the formed suspension of ethylene polymer particles in a solid-liquid separator into ethylene polymer particles and mother liquor, transferring a first part of the mother liquor into a work-up section including an evaporation unit for producing a wax-depleted portion of the mother liquor, wherein a protic agent is added to the part of the mother liquor which is transferred into the work-up section, and recycling a first part of the wax-depleted portion of the mother liquor to the polymerization reactor or the series of polymerization reactors.

The present invention relates to processes for preparing an aqueous polymer dispersion, aqueous polymer dispersions and a use of said dispersions in aqueous formulations for coatings, sealants and adhesive bonding. Further, the present invention relates to aqueous formulations for coatings, sealants and adhesive bonding comprising said dispersions and a process for preparing said aqueous formulations.

The present invention relates to processes for preparing an aqueous polymer dispersion, aqueous polymer dispersions and a use of said dispersions in aqueous formulations for coatings, sealants and adhesive bonding. Further, the present invention relates to aqueous formulations for coatings, sealants and adhesive bonding comprising said dispersions and a process for preparing said aqueous formulations.

Provided is a method for producing hollow resin particles in which a residual amount of a hydrocarbon solvent once held inside particles in a production process is reduced and particle breakage is suppressed. The method for producing hollow resin particles, which include preparing a mixture liquid containing a polymerizable monomer, a hydrocarbon solvent, a polymerization initiator and an aqueous medium, suspending the mixture liquid to prepare a suspension, subjecting the suspension to a polymerization reaction to prepare a precursor composition containing precursor particles having a hollow portion and including the hydrocarbon solvent in the hollow portion, and removing the hydrocarbon solvent from the precursor particles, wherein the polymerizable monomer contains a crosslinkable monomer in an amount of from 40% by mass to 100% by mass, and wherein the removal of the hydrocarbon solvent is performed by a specific method.

A process for producing protective-colloid-stabilized polymers based on ethylenically unsaturated monomers in the form of water-redispersible powders, by producing aqueous dispersions of protective-colloid-stabilized polymers based on ethylenically unsaturated monomers by polymerization of one or more ethylenically unsaturated monomers in an aqueous medium and drying said dispersions in the presence of one or more drying aids. The drying aids include a) one or more inorganic salts selected from the group of alkali metal sulfates and alkali metal sulfites and b) optionally one or more water-soluble organic polymers. The inorganic salts a) are present in the aqueous dispersions of the protective-colloid-stabilized polymers based on ethylenically unsaturated monomers in dissolved form after all drying aids have been added. The inorganic salts a) are employed as drying aids to an extent of 25% by weight based on the total weight of the drying aids.