Abstract: A polymerization process is provided for producing a butyl rubber with a bimodal molecular weight distribution which comprises introducing isobutylene, a conjugated diolefin monomer having from 4 to 8 carbon atoms, from about 1.times.10.sup.-5 to about 1.times.10.sup.-3 moles of an initiator component per mole of isobutylene, said initiator component being selected from the group consisting of an initiator component having the formula: ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 are selected from the group consisting of alkyl, aryl and aralkyl groups and can be the same or different and i is a positive whole number from 2 to 6, and an initiator component having an adamantyl nucleus bearing from 2 to 4 hydroxyl groups an inert organic solvent and from about 1.times.10.sup.-4 to about 1.times.10.sup.-3 moles of water per liter of inert organic solvent into a suitable reaction vessel at a temperature of from about -120.degree. C. to about -50.degree. C., adding a solution of from about 5.times.10.sup.

Abstract: A cross-linked composition produced by exposing a mixture including a telechelic polyisobutylene-containing base polymer which carries multiple terminal acrylate groups as a part thereof, a reactive diluent, and in some cases, a high-energy sensitizer, to high-energy radiation. The base polymer may also comprise a block copolymer which has polyisobutylene, and polydiene blocks as, for example, polyisoprene, and in which the polydiene blocks, advantageously partially cyclized, carry multiple acrylate groups as a part thereof. Among other things, the compositions have particular application in the formation of films useful in the electronic, biomedical, specialty adhesive, sealant, and other fields.

Abstract: A method for producing polymers with narrow molecular weight distribution which involves combining (1) an initiator component of the formula ##STR1## in which R.sub.1, R.sub.2, and R.sub.3 are alkyl, aryl, or aralkyl groups, and can be the same or different, and X is an acetate, etherate, a hydroxyl group, or a halogen, and i is a positive whole number, (2) a Lewis acid of the formula MX.sub.n in which M is titanium, aluminum, boron, or tin, X is a halogen, and n is a positive whole number, (3) an electron donor component having an electron donor number of from at least about 25 to no more than about 50, (4) a solvent for the preceding and (5) a hydrocarbon monomer component.

Abstract: Block copolymers compose a polyisobutylene rubbery soft segment of M.sub.n of about 5,000 to above 500,000 and glassy hard segments of M.sub.n of about 5,000 or higher and usually about 10,000 to 35,000 or more, are made by preparing a living polymer block of the polyisobutylene and then polymerizing on said living polyisobutylene block the glassy hard segments by adding thereto an electron donor having a donor number of 15 to 50 and then adding and polymerizing the monomers for the glassy hard segments. The monomers for the glassy hard segments are styrene and its derivatives and indene and its derivatives and mixtures thereof.

Abstract: A polymerization process for preparing triblock copolymers and multiblock copolymers. The process includes the polymerization of isobutylene below about -40.degree. C. in a reaction mixture which includes a titanium halide, a mixed solvent, and an initiator compound selected from the group consisting of cumyl ester and cumyl ether compounds. In at least some instances, the components are added in a particular order, sometimes together with a moisture scavenger. After formation of the polyisobutylene, a diene is added to the mixture containing the polyisobutylene and polymerized to form the desired copolymer. The diene portion of the copolymer may subsequently be cyclized to produce a copolymer exhibiting both thermoplastic and elastomeric properties. If desired the block copolymers can be subsequently modified to include functional side groups, or to provide photocuring capabilities.