Metallocene complexes represented by the structure below are useful for alpha olefin oligomerization in the presence of an activator to generate polyalphaolefins having a high percentage of vinylidene termination and relatively low Mn values.

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M is a group 4 transition metal. A is a bridging group having one bridging atom extending between a first indenyl ring and a second indenyl ring. Each X is independently an anionic ligand, or two Xs are joined and bound to M to form a metallocycle ring, or two Xs are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand. R.sup.1, R.sup.1′, R.sup.3, R.sup.3′, R.sup.4, R.sup.4′, R.sup.7 and R.sup.7′ are hydrogen. R.sup.5, R.sup.5′, R.sup.6, and R.sup.6′ are independently a C.sub.1-C.sub.10, optionally substituted, hydrocarbyl group, or R.sup.5 and R.sup.6 and/or R.sup.5′ and R.sup.6′ are bonded together to form an optionally substituted hydrocarbyl ring structure.

In at least one embodiment, a process to produce a poly alpha-olefin (PAO) includes introducing a first alpha-olefin to a first catalyst system comprising activator and a metallocene compound into a continuous stirred tank reactor or a continuous tubular reactor under first reactor conditions to form a first reactor effluent. The first alpha-olefin is introduced to the reactor at a flow rate of about 100 g/hr or more. The first reactor effluent includes at least 60 wt % of PAO dimer and 40 wt % or less of higher oligomers, where the higher oligomers are oligomers that have a degree of polymerization of 3 or more. The process includes introducing the first reactor effluent and a second alpha-olefin to a second catalyst composition including an acid catalyst in a second reactor to form a second reactor effluent comprising PAO trimer.

In at least one embodiment, a process to produce a poly alpha-olefin (PAO) includes introducing a first alpha-olefin to a first catalyst system comprising activator and a metallocene compound into a continuous stirred tank reactor or a continuous tubular reactor under first reactor conditions to form a first reactor effluent. The first alpha-olefin is introduced to the reactor at a flow rate of about 100 g/hr or more. The first reactor effluent includes at least 60 wt % of PAO dimer and 40 wt % or less of higher oligomers, where the higher oligomers are oligomers that have a degree of polymerization of 3 or more. The process includes introducing the first reactor effluent and a second alpha-olefin to a second catalyst composition including an acid catalyst in a second reactor to form a second reactor effluent comprising PAO trimer.

A 4-methyl-1-pentene polymer (X) wherein a content of a constitutional unit derived from 4-methyl-1-pentene is 90 to 100% by mol; a content of a constitutional unit derived from at least one olefin selected from ethylene and an α-olefin, other than 4-methyl-1-pentene, having 3 to 20 carbon atoms is 0 to 10% by mol; and the 4-methyl-1-pentene polymer satisfies certain requirements (a) to (f): (a) a meso diad fraction (m) measured by .sup.13C-NMR falling within a certain range; (b) a ratio of weight-average molecular weight Mw within a certain range; (c) a melt flow rate (MFR) within a certain range; (d) a cumulative weight fraction within a certain range; (e) a proportion of a polymer having a molecular weight of a certain range; and (f) a heat of fusion and a melting point of the 4-methyl-1-pentene polymer within certain ranges.

A 4-methyl-1-pentene polymer (X) wherein a content of a constitutional unit derived from 4-methyl-1-pentene is 90 to 100% by mol; a content of a constitutional unit derived from at least one olefin selected from ethylene and an α-olefin, other than 4-methyl-1-pentene, having 3 to 20 carbon atoms is 0 to 10% by mol; and the 4-methyl-1-pentene polymer satisfies certain requirements (a) to (f): (a) a meso diad fraction (m) measured by .sup.13C-NMR falling within a certain range; (b) a ratio of weight-average molecular weight Mw within a certain range; (c) a melt flow rate (MFR) within a certain range; (d) a cumulative weight fraction within a certain range; (e) a proportion of a polymer having a molecular weight of a certain range; and (f) a heat of fusion and a melting point of the 4-methyl-1-pentene polymer within certain ranges.

Unsaturated and hydrogenated polyalpha-olefin products can be made with a high selectivity toward vinylidenes and tri-substituted vinylenes combined, a high selectivity toward vinylidenes, and a low selectivity toward 1,2-di-substituted vinylenes by using a catalyst system comprising a metallocene compound having the following structure in the polymerization reaction: ##STR00001##

Unsaturated and hydrogenated polyalpha-olefin products can be made with a high selectivity toward vinylidenes and tri-substituted vinylenes combined, a high selectivity toward vinylidenes, and a low selectivity toward 1,2-di-substituted vinylenes by using a catalyst system comprising a metallocene compound having the following structure in the polymerization reaction: ##STR00001##

Unsaturated and hydrogenated polyalpha-olefin products can be made with a high selectivity toward vinylidenes and tri-substituted vinylenes combined, a high selectivity toward vinylidenes, and a low selectivity toward 1,2-di-substituted vinylenes by using a catalyst system comprising a metallocene compound having the following structure in the polymerization reaction: ##STR00001##

A process for the preparation of polyisobutene derivatives involves bringing an oxygen-containing gas in contact with polyisobutene, in the presence of a photosensitizer, and irradiating the reaction mixture. The polyisobutene derivatives are useful, for example, in hydrocarbon mixtures or hydrocarbon-containing oils.

A process for the preparation of polyisobutene derivatives involves bringing an oxygen-containing gas in contact with polyisobutene, in the presence of a photosensitizer, and irradiating the reaction mixture. The polyisobutene derivatives are useful, for example, in hydrocarbon mixtures or hydrocarbon-containing oils.