Oligomer oils and their manufacture

A process for the selective production of an oligomer oil comprising less than 25% oligomers that contain two or fewer monomeric units, at least 65% of oligomers that contain three monomeric units, and less than 15% of oligomers that contain four or more monomeric units comprising:

• (a) polymerizing a feed comprising one or more linear C4 to C20 monomeric 1-olefins having at least one hydrogen on the 2-carbon atom, at least two hydrogens on the 3-carbon atom and at least one hydrogen on the 4-carbon atom in the presence of a metallocene catalyst system comprising a bulky ligand transition metal complex of the stoichiometric Formula 1 and an activating quantity of an activator comprising an organoaluminum compound or a hydrocarbylboron compound or a mixture thereof:
• LmMXnX′p Formula 1
• wherein L is the bulky ligand, M is the transition metal, X and X′ may be the same or different and are independently selected from the group consisting of halogen, hydrocarbyl group and hydrocarboxyl group having 1-20 carbon atoms, wherein m is 1-3, n is 0-3, and p is 0-3 and the sum of the integers m+n+p corresponds to the transition metal valency, under reaction conditions such that there is formed a product mixture comprising an essentially terminally unsaturated viscous, essentially 1-olefin-containing poly (1-olefin) or copoly (1-olefin) of molecular weight between about 300 and about 10,000 that exhibits a terminal vinylidene content of more than 80%;
• and
• (b) oligomerizing at least a relatively lower molecular weight oligomeric fraction of the product mixture formed in step (a), the oligomeric mixture comprising oligomers having two monomeric units from the aforesaid monomeric 1-olefins fed to step (a), in the presence of an acidic oligomerization catalyst under reaction conditions such that there is formed a resulting product mixture comprising less than 25% by weight of oligomers that contain two or fewer monomeric units, at least 65% by weight of oligomers that contain three monomeric units, and less than 15% by weight of oligomers having four or more monomeric units.