The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and an ashless dispersant. The ashless dispersant may be selected from succinimide compounds prepared from aliphatic or aromatic amines.

A multi-functional olefin copolymer viscosity index improver and a lubricating oil composition including such lubricant additive that provides improved viscometric properties and helps reduce low speed pre-ignition events at the same time. In one approach, the multi-functional olefin copolymer viscosity index improver is silicone functionalized and includes an acylated olefin copolymer with aminosilane or aminosiloxone pendant or side groups.

The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100° C. of 1.00 to 2.50 mm.sup.2/s; and an ester oil (B2) having a kinematic viscosity at 100° C. of 2.51 to 5.00 mm.sup.2/s:

##STR00001##

wherein R.sup.1 is a hydrogen atom or a methyl group; —X.sup.1— is a group represented by —O—, —O(AO).sub.m-, or —NH—, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; R.sup.2 is a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.

Compositions, including dispersants, derived from substituted succinic anhydrides and aromatic polyamines. Methods for making compositions, the methods including contacting a substituted succinic anhydride and an aromatic polyamine. Lubricants that include a composition derived from a substituted succinic anhydride and an aromatic polyamine. Methods for improving soot performance.

A lubricating oil composition may be used for lubrication of a shock absorber, and may include a base oil (A), a polyalkyl (meth)acrylate (B) having a weight average molecular weight in a range of from 150,000 to 900,000, and an olefin copolymer (C) having a weight average molecular weight of 100,000 or less.

The present invention aims to provide a viscosity index improver composition and a lubricating oil composition having a low HTHS viscosity at 100° C., an excellent shear stability, and an excellent low temperature viscosity. The present invention relates to, for example, a viscosity index improver composition (C), containing: a copolymer (A) containing a polyolefin-based monomer (a) represented by the following formula (1) as a constituent monomer; a copolymer (B) containing a (meth)acrylic acid alkyl ester (c) having a C12-C15 straight-chain or branched alkyl group and a (meth)acrylic acid alkyl ester (d) having a C16-C20 straight-chain or branched alkyl group as constituent monomers; and a base oil, wherein a weight average molecular weight ratio {(A)/(B)} of the copolymer (A) to the copolymer (B) is 2 to 55, and a weight ratio (A/B) of the copolymer (A) to the copolymer (B) constituting the viscosity index improver composition (C) is 5 to 100: ##STR00001##

A polymeric material mixture comprising a fluorine-containing polymer, a siloxane polymer, and at least two polymer processing additives (PPA), wherein the at least two polymer processing additives have different chemistries. For example, there can be a flexible coextruded pipe for providing a protective housing for cables, fluids, sludge or solids, the pipe comprising a pair of telescopically related inner and outer layers, where said inner layer is lubricated with the polymeric material mixture.

An additive composition contains a viscosity index improver and a pour point depressant. A process can be used for preparing the additive composition. The additive composition can be used as a lubricant additive in a lubricating oil formulation, and lubricating oil formulations can contain the additive composition.

The present invention relates to a mechanochemical based synthesis of perfluoropyridine monomers, polymers made using such monomers and methods of making and using articles comprising such polymers. Such perfluoropyridine monomers are easily chemically tuned have the strength needed for high temperature applications and the flexibility needed for low temperature applications. In addition, to the aforementioned monomers, a mechanochemical based synthesis for such perfluoropyridine monomers is provided. All of the aforementioned performance application advantages are also found in polymers comprising Applicants' perfluoropyridine monomers.

The invention relates to a poly alkyl(meth)acrylate polymer comprising polybutadiene-based monomer units and a process for preparing the same. The invention also relates to the use of said polymer as a viscosity index improver in lubricant formulation and to lubricant compositions comprising said polymer.