Patent ID: 6222081
Filing Date: 2001-04-24
Classification: C08F,C10L

Abstract:
In a method for decreasing the cold filter plugging point of middle distillates, the improvement comprising adding thereto ethylene copolymers obtained by polymerizing ethylene and alpha olefin monomers in the presence of catalysts comprising the reaction product of:1) a bis-cyclopentadienyl having the formula:(Cp.sub.1 Cp.sub.2)--M--(L.sub.2 L.sub.3)containing groups with oxygen bound to a transition metal, whereinM is a metal from group IIIb to the group IIb or of the lanthanides series of the periodic table; Cp.sub.1 and Cp.sub.2, are equal to or different from each other and are selected from the following groups bound to M, with an eta 5 bond: cyclopentadiene, indene, fluorene and derivatives thereof, substituted in the case of indene and fluorene by one or more hydrogenated phenylic rings and with substituents both in the phenylic and cyclopentadienylic rings, also with heteroatoms; or with .pi. bonds for cyclooctatriene; or said groups Cp.sub.1 and Cp.sub.2 constrained with M by a bivalent linking bridge --R--, wherein R is an alkylene of from 1 to 4 carbon atoms, --Si(R').sub.2 -- wherein R' is an alkyl of from 1 to 10 carbon atoms; or an aryl optionally containing the heteroatoms O and N, or alkylaryl or arylalkyl of from 7 to 20 carbon atoms;L.sub.2 or L.sub.3, are equal to or different from each other and represent an OR.sub.a group wherein R.sub.a is an aryl group, optionally the carbon atoms of the ring are substituted by heteroatoms, and optionally containing alkylic substituents from 1 to 10 carbon atoms with2) a co-catalyst having the formula (L.sub.1 --H).sup.+ (BQ.sub.4).sup.- wherein(L.sub.1 --H).sup.+ is a Bronsted acid,B is boron in the valence 3;Q is equal to or different from each other, and it is selected from the group consisting of: hydrides, halides, alkyls, and aryls optionally substituted with halogens, alkoxides, aryloxides, dialkylamido, or R.sub.0 COO--, wherein R.sub.0 has from 1 to 20 carbon atoms, with the proviso that Q can be equal to halide only once.