The present invention relates to an aqueous emulsion comprising: a) from 50% to 60% of an organic phase dispersed in an aqueous phase, said organic phase containing a mixture including from 24% to 30%, calculated with respect to the final emulsion, of ethylene-vinyl acetate copolymers and/or polyalkyl(meth)acrylates, indicated in the present description as polymeric component, and a high-boiling organic solvent, or a mixture of said solvents; b) a primary emulsifier at a concentration higher or equal to 0.1% and lower than or equal to 3% by weight, calculated with respect to the final emulsion; c) from 37% to 47% of an aqueous phase; wherein the ratio between said polymer component and said organic solvent in the final aqueous emulsion is at least 1/1 and where the organic solvent and any polymer of the polymeric component have a Hildebrand solubility parameter δ such that, the difference (δ.sub.solvent_δ.sub.polymer) is lower than 2 in absolute value for any polymer of the polymeric component.

A method of improving the low temperature properties of a middle distillate fuel composition comprising: (a) a nitrogen-containing dispersant; and (b) one or more low temperature property enhancers which are not fumarate vinyl ester copolymers and which are selected from (x) wax antisettling additives; (y) middle distillate flow improvers and mixtures thereof; the method comprising adding to the fuel an additive (c) which is a copolymer comprising units of formula (A): and units of formula (B): wherein R is an alkyl group and each of R.sup.1 and R.sup.2 is an alkyl group.

##STR00001##

Novel uses of copolymers for removing and/or reducing the level of deposits in the fuel system and/or injection system of direct injection diesel and/or gasoline engines are provided. What is provided is the use of particular copolymers as fuel additive or lubricant additive; to processes for preparation of such additives, and fuels and lubricants added therewith, such as, more particularly, as a detergent additive; to use of these copolymers for reducing the level of or preventing deposits in the fuel systems and especially the injection systems of direct injection diesel engines, especially in common rail injection systems, for reducing the fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems, and for minimizing power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems; and as an additive for gasoline fuels, especially for operation of DISI engines.

The invention relates to a polymer composition that can be obtained by means of the free radical polymerisation of A) 95-40 wt. % of alkyl (meth)acrylate containing Ai) 20-95 wt. % of at least one alkyl (meth)acrylate with 16 to 40 C-atoms in the alcohol group, and Aii) 5-80 wt. % of at least one (meth)acrylic acid ester of a C.sub.8-C.sub.22 alcohol carrying a C.sub.6-C.sub.20 alkyl group in the 2-position relative to the hydroxyl group, in the presence of B) 5-60 wt. % ethylene copolymer. The invention also relates to a method for producing same and to the use of same as a flow improver for mineral oils and mineral oil distillates.

A drag reducing composition comprises a sealed temporary container; and a drag reducing agent and up to 20 weight percent of a dispersing fluid disposed in the sealed temporary container. The drag reducing agent comprises polyolefin particles having a particle size of about 10 to about 2,000 microns; and the dispersing fluid comprising water, an alcohol, a hydrocarbon, or a combination comprising at least one of the foregoing.

A drag reducing agent has a core comprising a polyolefin; and a temporary container encapsulating the core. The temporary container contains a container material, which includes an ethylene vinyl acetate copolymer, an ethylene vinyl alcohol copolymer, a polyvinylpyrrolidone, an ethylene vinylpyrrolidone copolymer, a vinylpyrrolidone vinyl acetate copolymer, a polyvinyl acetate, a polyvinyl alcohol, a polyethylene oxide, a polyethylene glycol, polyvinylidene chloride, a polysaccharide or its derivative, or a combination comprising at least one of the foregoing. A largest dimension of the drag reducing agent is greater than about 1,000 microns.

A method making fuel oil from refining residuals. Refining residuals are mixed with a diluent and an additive. Preferred diluents include diesel and reformed naphtha and combinations thereof. The additive is believed to be a cross-linked cyclic anhydride copolymer having an intrinsic viscosity (limiting viscosity, ) of between about 0.10 and 3.0 deciliters per gram and an average molecular weight between about 3,000 and 3,000,000. The additive includes excess aromatic hydrocarbons and a surfactant. In the preferred embodiment, the diluent and the residuals are mixed together in a ratio of about 3:1, by weight. The additive is introduced to this mixture in the amount of about 0.10 to 0.25 percent by weight. The components are thoroughly combined to yield a fuel oil having a viscosity that is about 25 to as much as about 70 percent lower than the viscosity of the same residual/diluent mixture lacking the additive.

The present invention relates to an aqueous emulsion comprising: a) from 50% to 60% of an organic phase dispersed in an aqueous phase, said organic phase containing a mixture including from 24% to 30%, calculated with respect to the final emulsion, of ethylene-vinyl acetate copolymers and/or polyalkyl(meth)acrylates, indicated in the present description as polymeric component, and a high-boiling organic solvent, or a mixture of said solvents; b) a primary emulsifier at a concentration higher or equal to 0.1% and lower than or equal to 3% by weight, calculated with respect to the final emulsion; c) from 37% to 47% of an aqueous phase; wherein the ratio between said polymer component and said organic solvent in the final aqueous emulsion is at least 1/1 and where the organic solvent and any polymer of the polymeric component have a Hildebrand solubility parameter such that, the difference (.sub.solvent_.sub.polymer) is lower than 2 in absolute value for any polymer of the polymeric component.

The invention provides dispersions comprising I) at least one oil-soluble polymer effective as a cold flow improver for mineral oils, II) at least one organic, water-immiscible solvent, III) a dispersant comprising, based on the total amount of dispersant, a) 10-90% by weight of a salt of an ethercarboxylic acid and b) 90-10% by weight of a nonionic surfactant, IV) water and V) at least one organic, water-miscible solvent.

A copolymer obtained by copolymerization of at least: an apolar monomer (m.sub.a) with the following formula (I), where u=0 or I, w=0 or I, E=-0- or NH(Z), or OCO, or NHCO or CONH, wherein Z is H or an alkyl group, and G is a group selected among an alkyl, an aromatic ring and an arylalkyl; and a polar monomer (m.sub.b) selected among those of the following formula (II), wherein t=0 or I, Q is selected among the oxygen atom and the NR group, wherein R is selected among a hydrogen atom and hydrocarbon chains, and R is a hydrocarbon chain substituted by at least one quaternary ammonium group and optionally one or more hydroxyl groups. The invention also relates to the use of such a copolymer as a detergent additive in a liquid fuel of an internal combustion engine.