Fuel oils with improved cold flow properties - contg. synergistic combination of aliphatic and aromatic copolymers

摘要

Wax-contg. distillate fuel oils (boiling range 120-600 degrees C, final b.pt. >370 degrees C) with improved cold flow properties contain 0.001-0.5 wt.% of a synergistic combination of (a) an aliphatic copolymer acting as a nucleator for wax crystn. and (b) an oil-soluble aromatic copolymer, with an (a):(b) wt. ratio of 1:0.2-20. Component (a) is a copolymer of ethylene and a vinyl ester of a 1-8C satd. aliphatic monocarboxylic acid. It has a Mn of 500-50,000 and contains 3-40 mles of ethylene per mole of vinyl ester. Component (b) is a copolymer of an 8-20C monovinyl aromatic monomer and an ester obtd. by reacting maleic anhydride, acrylic acid or methacrylic acid with a 6-22C satd. straight-chain alcohol. It has a Mn of 500-50,000. The additive combinations give large decreases in cold filter plugging point (CFPP).