A defoaming agent including a polymer, the polymer including a repeating unit represented by the following general formula (1); and a repeating unit represented by the following general formula (3):

##STR00001##

wherein in the general formula (1), X.sup.1 is a repeating unit obtainable by polymerization of a first ethylenic unsaturated group; Y.sup.1 is a side chain including a linear or branched polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 300; and Z.sup.1 is a linking group linking the repeating unit X.sup.1 and the side chain Y.sup.1;

##STR00002##

wherein in the general formula (3), X.sup.2 is a repeating unit obtainable by polymerization of a second ethylenic unsaturated group, Y.sup.2 is a C.sub.1-30 hydrocarbyl side chain; and Z.sup.2 is a linking group linking the repeating unit X.sup.2 and the side chain Y.sup.2.

This invention encompasses lubricating oil compositions comprising a base oil, a biodiesel fuel and a dispersant. A method for inhibiting viscosity increase in a diesel engine fueled at least in part with a biodiesel fuel is also described.

A polymer comprises a polymeric backbone, at least one piperidine ester moiety extending from the polymeric backbone, and generally at least one C.sub.8 to C.sub.22 ester moiety extending from the polymeric backbone. The polymer is useful for adjusting the total base number and viscosity index of a lubricant composition. The lubricant composition generally comprises a base oil in addition to the polymer. A method of forming the polymer comprises the steps of providing a first component and providing a second component. The first component comprises at least one of A1) a piperidine methacrylate, or A2) a methacrylate. The second component comprises at least one of B) a C.sub.8 to C.sub.22 methacrylate. Optionally, the method further comprises the step of providing a third component, which comprises at least one of C) a piperidine-ol. The method further comprises at least one reaction step involving the aforementioned components to form the polymer.

A heat treatment oil composition is provided that is capable of reducing the fluctuation in cooling capability among components subjected to mass quenching while retaining a cooling capability equivalent to the No. 1 oil of Class 2 of JIS K2242:2012 in a heat treatment of a metal material, such as quenching, and is capable of suppressing deterioration in cooling capability thereof with the lapse of time under repetition of the heat treatment. The heat treatment oil composition contains (A) a base oil and (B) at least one selected from a petroleum resin and/or a derivative of a petroleum resin, and has a characteristic time obtained from a cooling curve obtained according to the cooling capability test method of JIS K2242:2012 of 1.00 second or less and a 300 C. number of second, which is a cooling time from 800 C. to 300 C. in the cooling curve, of 6.00 seconds or more and 14.50 seconds or less.

A polymer comprises a polymeric backbone, at least one piperidine ester moiety extending from the polymeric back-bone, and generally at least one C.sub.8 to C.sub.22 ester moiety extending from the polymeric backbone. The polymer is useful for adjusting the total base number and viscosity index of a lubricant composition. The lubricant composition generally comprises a base oil in addition to the polymer. A method of forming the polymer comprises the steps of providing a first component and providing a second component. The first component comprises at least one of A1) a piperidine methacrylate, or A2) a methacrylate. The second component comprises at least one of B) a C.sub.8 to C.sub.22 methacrylate. Optionally, the method further comprises the step of providing a third component, which comprises at least one of C) a piperidine-ol. The method further comprises at least one reaction step involving the aforementioned components to form the polymer.

The disclosed technology relates to a dispersant composition comprising the reaction product of a polyolefin acylating agent and an amine terminated or hydroxyl terminated polyether. In addition, the technology relates to lubricating compositions containing the dispersant composition and an optional synergistic amount of another dispersant, as well as methods of employing the dispersant composition in an engine and engine oils.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

Polymeric compositions obtainable by free-radical polymerization of at least two different alkyl (meth)acrylates in the presence of at least one ethylene-vinyl ester copolymer, the alkyl (meth)acrylates used being a mixture comprising alkyl (meth)acrylates having linear C.sub.12- to C.sub.60-alkyl radicals and different alkyl (meth)acrylates having linear C.sub.1- to C.sub.11-alkyl radicals and/or branched C.sub.4- to C.sub.60-alkyl radicals and/or cyclic C.sub.6- to C.sub.20-alkyl radicals. The use of such polymeric compositions as pour point depressants for crude oils, mineral oils or mineral oil products.

The disclosed technology relates to a dispersant composition comprising the reaction product of a polyolefin acylating agent and an amine terminated or hydroxyl terminated polyether. In addition, the technology relates to lubricating compositions containing the dispersant composition and an optional synergistic amount of another dispersant, as well as methods of employing the dispersant composition in an engine and engine oils.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.