Abstract:
PROBLEM TO BE SOLVED: To provide a viscosity index improver which realizes excellent shear stability of a lubricant composition and low HTHS viscosity of the lubricant composition and hardly increases low-temperature viscosity of the lubricant composition.SOLUTION: The viscosity index improver contains a (co)polymer comprising as an essential constituent monomer a monomer represented by the specified general formula (1) or (2).
Abstract:
PROBLEM TO BE SOLVED: To provide a viscosity index improver excellent in shear stability.SOLUTION: There is provided a viscosity index improver (X) which is composed of a (co)polymer (A) having a(meth)acrylic acid alkyl ester (a) having a branched alkyl group having 5 to 36 carbon atoms as an essential constituent monomer, wherein (A) has a weight average molecular weight of 150000 to 500000 and a molecular weight distribution of 2.0 to 3.5 and a solubility parameter of 7.3 to 9.5 (cal/cm).
Abstract:
PROBLEM TO BE SOLVED: To provide an additive showing an abrasion-decreasing effect in a lubricating oil composition.SOLUTION: A graft copolymer is obtained by manufacturing at least one kind of a graft trunk polymer by radically polymerizing a monomer composition (A) having 0 to 40 mass%, based on the mass of the monomer composition (A), of one or more kinds of ethylenic unsaturated ester compounds represented by formula (I) and 60 to 100 mass%, based on the mass of the monomer composition (A), of one or more kinds of ethylenic unsaturated ester compounds represented by formula (II); and then by grafting a monomer composition (B) having 20 to 100 mass% of at least one kind of a monomer containing a group having at least one nitrogen to the graft trunk polymer, (wherein the graft copolymer contains at most 200 ppm of sulfur, and the ratio of the mass of the monomer composition (A) to the mass of the monomer composition (B) is 99.7:0.3 to 80:20).
Abstract:
PROBLEM TO BE SOLVED: To provide a process for preparing of a polymer having at least one of low polydispersity, low temperature viscosity property, high temperature viscosity property, and shear stability and capable of adding dispersing and/or viscosity adjusting proprties; and to provide a process for preparing a composition thereof.SOLUTION: There is provided the method for preparing a polymer through the following steps: (1) a step of forming a polymer chain by contact with a free radical initiator, a chain transfer agent containing a thiocarbonyl thio group and free a radical leaving group, and a radically polymerizable monomer; and (2) a step of contacting the polymer chain in step (1) with at least one of polyvalent coupling agent, polymerization inhibitor, grafting/acylating agent, amine, and lubricating viscous oil. Also, provided are the composition of this polymer and use thereof.
Abstract:
Dielectric fluids comprising oil fractions derived from highly paraffinic wax are provided. Further provided are processes for making these dielectric fluids comprising oil fractions derived from highly paraffinic wax. The dielectric fluids are useful as insulating and cooling mediums in new and existing power and distribution electrical apparatus, such as transformers, regulators, circuit breakers, switchgear, underground electrical cables, and attendant equipment.