A composition comprising olefin oligomers of one or more olefin monomers, the olefin monomers comprising a branched C10 olefin monomer comprising i) 3-propyl-1-heptene, ii) 4-ethyl-1-octene, iii) 5-methyl-1-nonene, or iv) any combination thereof. A composition comprising substantially hydrogenated olefin oligomers, wherein the olefin oligomers are oligomers of one or more olefin monomers, the olefin monomers comprising a branched C10 olefin monomer comprising i) 3-propyl-1-heptene, ii) 4-ethyl-1-octene, iii) 5-methyl-1-nonene, or iv) any combination thereof. A process comprising a) contacting 1) a catalyst system and 2) a monomer feedstock comprising a branched C10 olefin monomer comprising i) 3-propyl-1-heptene, ii) 4-ethyl-1-octene, iii) 5-methyl-1-nonene, or iv) any combination thereof in a reaction zone; and b) forming olefin oligomers.