Abstract: There is disclosed a process for polymerizing a cationically polymerizable olefin comprising the step of polymerizing at least one cationically polymerizable olefin at a subatmospheric pressure in the presence of a cationic polymerization catalyst system which comprises an initiator and an activator, which together form a reactive cation and non-co-ordinating anion, the activator being prepared by the reaction of a metalloid compound of formula (R1R2R3)M with a co-initiator, the co-initiator being selected from the group consisting of an alcohol, a thiol, a carboxylic acid, a thiocarboxylic acid and the like.

Abstract: There is disclosed a process for polymerizing a cationically polymerizable olefin comprising the step of polymerizing at least one cationically polymerizable olefin at a subatmospheric pressure in the presence of a cationic polymerization catalyst system which comprises an initiator and an activator, which together form a reactive cation and non-co-ordinating anion, the activator being prepared by the reaction of a metalloid compound of formula (R1R2R3)M with a co-initiator, the co-initiator being selected from the group consisting of an alcohol, a thiol, a carboxylic acid, a thiocarboxylic acid and the like.

Abstract: Iso-butylene based polymers and particularly butyl rubber may be polymerised from iso-butylene or iso-butylene/isoprene mixtures respectively using a metallocene type catalyst. In particular, polymerization or co-polymerization takes place very rapidly under anhydrous and anaerboic conditions at temperatures between -100.degree. C. and -20.degree. C. in the presence an initiator co-initiator system comprising Cp'MXX'X"/BRR'R" in an organic solvent such as toluene, where Cp' is a .pi.-bonded cyclopentadienyl or substituted cyclopentadienyl ligand; M is selected from titanium, zirconium and hafnium; XX' and X" are the same or different anionic groups containing 1-20 nonhydrogen groups; B is boron; and R, R' and R" are the same or different anionic groups containing 1-30 nonhydrogen groups.

Abstract: High molecular weight syndiotactic polystyrene having greater than 96% syndiotacticity can be produced in very high yield (greater than 92%) by polymerizing styrene monomer, under rigorously anhydrous conditions, with a catalyst comprising Cp*M(CH.sub.3).sub.3, where Cp* is a single .eta..sup.5 -cyclopentadienyl or an .eta..sup.5 -cyclopentadienyl group optionally covalently bonded to M through a substituent, and M is selected from Ti, Zr, Hf and a co-catalyst comprising B(C.sub.6 F.sub.5).sub.3 dissolved in an aromatic solvent such as toluene or styrene, at carefully controlled temperatures in the range -15.degree. C. to +50.degree. C. The rapid rate of polymerization and high yield make the production of hard, rigid products by reaction injection moulding possible.

Abstract: A process for the production of high molecular weight poly(vinyl ethers) and the like in which a selected monomer is polymerized in the presence of a metallocene-type catalyst is described. Vinyl ether monomers, N-vinylcarbazole and 1.5-10 hexadiene can be polymerized, in high yield using an initiator of the formula Cp*TiMe.sub.3 in the presence of a co-initiator of the formula B(C.sub.6 F.sub.5).sub.3. Novel dihydropyran polymers, such as poly 3,4-dihydropyran have also been produced.