An olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, or a nitrogen compound quaternized with epoxide in the presence of an olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, can be used as a fuel additive or lubricant additive. Processes can be used for preparing additives of this kind and fuels and lubricants additized therewith, such as a detergent additive. These additives, fuels, and lubricants can be used for reduction or prevention of deposits in injection systems of direct injection diesel engines, especially in common rail injection systems: for reduction of fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems; and for minimization of power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems. The additives can also be used for gasoline fuels, especially for operation of DISI engines.

An olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, or a nitrogen compound quaternized with epoxide in the presence of an olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, can be used as a fuel additive or lubricant additive. Processes can be used for preparing additives of this kind and fuels and lubricants additized therewith, such as a detergent additive. These additives, fuels, and lubricants can be used for reduction or prevention of deposits in injection systems of direct injection diesel engines, especially in common rail injection systems; for reduction of fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems; and for minimization of power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems. The additives can also be used for gasoline fuels, especially for operation of DISI engines.

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.

A fuel additive composition includes: (a) one or more copolymers including:

at least one unit of formula (I) below:

##STR00001##

with u=0 or 1, E=—O— or —N(Z)—, or —O—CO—, or —CO—O— or —NH—CO— or —CO—NH—, with Z representing H or a C.sub.1-C.sub.6 alkyl group, G represents a group chosen from a C.sub.1-C.sub.34 alkyl, an aromatic nucleus, an aralkyl including at least one aromatic nucleus and at least one C.sub.1-C.sub.34 alkyl group, and —at least one unit of formula (II) below:

##STR00002##

in which R.sub.1″ is chosen from a hydrogen atom and a methyl group, Q is chosen from an oxygen atom and a group —NR′— with R′ being chosen from a hydrogen atom and C.sub.1 to C.sub.12 hydrocarbon-based chains, R comprises a C.sub.1 to C.sub.34 hydrocarbon-based chain substituted with at least one quaternary ammonium group.

A method minimizes power loss in a direct injection diesel engine by adding a copolymer to a diesel fuel composition. The copolymer contains, in a copolymerized form, (A) maleic anhydride, (B) an α-olefin having from 12 to 30 carbon atoms, (C) optionally an additional aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different from monomer (B), and (D) optionally an additional copolymerizable monomer other than monomers (A), (B) and (C). Monomer (D) can be a vinyl ester, a vinyl ether, a (meth)acrylic ester of an alcohol having at least 5 carbon atoms, an allyl alcohol or an ester thereof, a N-vinyl compound, an ethylenically unsaturated aromatic, an α,β-ethylenically unsaturated nitrile, a (meth)acrylamide, or an allylamine. Anhydride functionalities present in the copolymer are partly reacted with at least one compound (E) comprising an alcohol group and/or an amino group, and the anhydride functionalities present are hydrolyzed.

Polymeric mist control materials, methods of forming polymeric mist control materials, and methods of using such materials for mist control are provided. The polymeric mist control additives are formed of molecules comprised predominantly of monomers that confer high solubility in fuel and include associative groups that attract each other in donor-acceptor manner, and are incorporated such that multiple associative groups are in close proximity (“clusters”), such that the clusters are separated by very long non-associative sequences.

A method for minimizing power loss, reducing a fuel consumption and/or for reducing and/or avoiding deposits in a fuel system in the direct injection diesel engines. The method contains adding a copolymer to a fuel composition, wherein the copolymer contains, in a copolymerized form: (A) an ethylenically unsaturated mono- or dicarboxylic acid or a derivative thereof, (B) an -olefin having from 12 to 30 carbon atoms, (C) optionally an additional aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different from monomer (B) and (D) optionally an additional copolymerizable monomers other than monomers (A), (B) and (C), anhydride or carboxylic acid functionalities present in the copolymer are partly reacted with at least one compound (E) comprising an alcohol group and/or an amino group, and the anhydride functionalities present in the copolymer are hydrolysed and/or carboxylic ester functionalities present in the copolymer are partly hydrolyzed.

Disclosed are cloud point depressants and methods of making and using them. The disclosed cloud point depressants comprise copolymers of a maleic moiety polymerized with alpha olefins and then contacted with an aliphatic tertiary amine to provide a cloud depressant reaction product. When the disclosed reactions products are added to middle distillate fuels or blends of middle distillate fuels with biodiesel, the cloud point depressants inhibit the precipitation of waxes and/or biowaxes in the fuels and the fuels exhibit reduced precipitation, gelling, and/or crystallization when subjected to low or cold temperatures.

The invention relates to oil-in-water (water continuous) emulsions that can be used as fuels, and which have high static and dynamic stability, to a process for their preparation, and to fuel compositions comprising such emulsions.

The invention relates to the use, in order to prevent deposits at low temperature on the fuel intake valves in indirect injection spark ignition engines, of one or more copolymer(s) comprising: at least one unit of following formula (I):

##STR00001## and units of following formula (II):

##STR00002##

The copolymers according to the invention are very particularly effective in preventing and/or cleaning the deposits on the valves while preventing the latter from sticking at low temperature.