Polymer combinations useful in fuel oil to improve cold flow properties

Claim 1

A fuel oil composition comprising a major proportion of a distillate petroleum fraction having an atmospheric boiling range of from about 120° C. to about 400° C. and from about 0.005 to 0.1 wt. % of a synergistic flow and filterability improving combination of the following: (a) from 0.2 to 8 parts by weight of a polymeric substance selected from the group consisting of (i) poly (isomerized C 12 -C 50 alpha monoolefin) wherein said monoolefin contains at least 60% by weight of C 16 to C 32 alpha monoolefin, said poly (isomerized C 12 -C 50 alpha monoolefin) having a number average molecular weight of about 400 to 3000 and (ii) aromatics having 1 to 3 benzene rings alkylated with said poly (isomerized C 12-50 monoolefin); and (b) per part by weight of a lubricating oil pour depressant having a number average moleuclar weight of about 800 to 50,000 and having pendant alkyl groups of 6 to 32 carbons atoms, said pour depressant being selected from the group consisting of (i) the condensation product of chlorinated C 16-40 paraffin containing about 5 to 25 wt. % chlorine and an aromatic hydrocarbon, and (ii) a sulfone copolymer of sulfur dioxide and C 14-20 alpha olefin, wherein said synergistic combinations are combinations selected from the group consisting of (a) (i) with (b) (ii); (a) (ii) with (b) (i); and (a) (ii) with (b) (ii).