The invention relates to an efficient process for the preparation of isoolefin polymers such as polyisobutene or butyl rubber by polymerization of isobutene and optionally further monomers in the presence of an initiator system prepared by continuously contacting at least one boron or aluminium compound and at least one initiator.

The invention relates to an efficient process for the preparation of isoolefin polymers such as polyisobutene or butyl rubber by polymerization of isobutene and optionally further monomers in the presence of an initiator system prepared by continuously contacting at least one boron or aluminium compound and at least one initiator.

An ink composition includes water, a co-solvent, a colorant, and a modified polymer or copolymer additive. The modified polymer or copolymer additive is selected from the group consisting of i) a hydrolyzed poly(isobutylene-alt-maleic anhydride), ii) a hydrolyzed poly(maleic anhydride-alt-1-octadecene), and iii) a modified polymer or copolymer. The modified polymer or copolymer includes a repeating unit of a backbone chain, and a long chain pendant group attached to a carbon atom of the repeating unit. In the backbone chain, the long chain pendant group of the repeating unit is separated by fewer than 8 spacer carbon atoms from another long chain pendant group of an adjacent repeating unit.

An ink composition includes water, a co-solvent, a colorant, and a modified polymer or copolymer additive. The modified polymer or copolymer additive is selected from the group consisting of i) a hydrolyzed poly(isobutylene-alt-maleic anhydride), ii) a hydrolyzed poly(maleic anhydride-alt-1-octadecene), and iii) a modified polymer or copolymer. The modified polymer or copolymer includes a repeating unit of a backbone chain, and a long chain pendant group attached to a carbon atom of the repeating unit. In the backbone chain, the long chain pendant group of the repeating unit is separated by fewer than 8 spacer carbon atoms from another long chain pendant group of an adjacent repeating unit.

Although polyolefin elastomers are widely employed commodity polymers, there are shortcomings of this class of polymers for certain applications. For example, the rheological properties of some polyolefin elastomers may be insufficient to provide the green strength or low shear viscosity necessary to form stable foams, or to provide sufficient viscosity modification effects when present in a solvent. Cationomeric modification of polyolefin elastomers may alleviate these difficulties. Such polyolefin elastomers may feature a random cationomeric polyolefin copolymer comprising at least a first monomer and a second monomer, in which the first monomer is a neutral monomer and the second monomer has a side chain bearing a cationic moiety. The polyolefin elastomers may be present in foamed polyolefin compositions comprising a gas component and/or in liquid compositions comprising a solvent in which the polyolefin elastomer is dissolved.

Although polyolefin elastomers are widely employed commodity polymers, there are shortcomings of this class of polymers for certain applications. For example, the rheological properties of some polyolefin elastomers may be insufficient to provide the green strength or low shear viscosity necessary to form stable foams, or to provide sufficient viscosity modification effects when present in a solvent. Cationomeric modification of polyolefin elastomers may alleviate these difficulties. Such polyolefin elastomers may feature a random cationomeric polyolefin copolymer comprising at least a first monomer and a second monomer, in which the first monomer is a neutral monomer and the second monomer has a side chain bearing a cationic moiety. The polyolefin elastomers may be present in foamed polyolefin compositions comprising a gas component and/or in liquid compositions comprising a solvent in which the polyolefin elastomer is dissolved.

Although polyolefin elastomers are widely employed commodity polymers, there are shortcomings of this class of polymers for certain applications. For example, the rheological properties of some polyolefin elastomers may be insufficient to provide the green strength or low shear viscosity necessary to form stable foams, or to provide sufficient viscosity modification effects when present in a solvent. Cationomeric modification of polyolefin elastomers may alleviate these difficulties. Such polyolefin elastomers may feature a random cationomeric polyolefin copolymer comprising at least a first monomer and a second monomer, in which the first monomer is a neutral monomer and the second monomer has a side chain bearing a cationic moiety. The polyolefin elastomers may be present in foamed polyolefin compositions comprising a gas component and/or in liquid compositions comprising a solvent in which the polyolefin elastomer is dissolved.

A medical rubber composition can contain, comprise, consist, or consist essentially of: (a) an isobutylene-isoprene rubber: (b) a diene-based rubber; and a silica having a BET specific surface area not lower than 130 m.sup.2/g. An amount of (a) the isobutylene-isoprene rubber contained in 100 parts by mass of a rubber component composed of (a) the isobutylene-isoprene rubber and (b) the diene-based rubber can be larger than 30 parts by mass and smaller than 55 parts by mass.

A medical rubber composition can contain, comprise, consist, or consist essentially of: (a) an isobutylene-isoprene rubber: (b) a diene-based rubber; and a silica having a BET specific surface area not lower than 130 m.sup.2/g. An amount of (a) the isobutylene-isoprene rubber contained in 100 parts by mass of a rubber component composed of (a) the isobutylene-isoprene rubber and (b) the diene-based rubber can be larger than 30 parts by mass and smaller than 55 parts by mass.

A thermoplastic wrap film including polyisobutylene succinic anhydride (PIBSA) is disclosed herein.