Rohm Gmbh

Rohn Gmbh

Heinz Jost

Horst Pennewiss

Helmut Knoell

Ulrich Schoedel

Franz Wenzel

Gerhard Markert

Hellmuth Knoell

Hans Pilz

Claudia Beyer

Ruediger Jelitte

Helmuth Knoell

Rainer Benda

Synthetic oils comprising 5-100 percent by weight of an oligomer of

Synthetic oligomeric oils

Multifunctional additives for lubricating oils containing n-paraffins, said additives comprising a solvent and a blend of polymers containing

Addives for paraffinic lubricants

Additives for n-paraffin-containing lubricating oils, which additives are mixtures of acrylates containing

Lubricating oil additives

Polymers adaptable to use as pour point lowering additives for petroleum oils, said polymers comprising as comonomers therein

Pour point improving additives for mineral oils

Multirange lubricating oils having high shear stability comprising paraffinic oils as their base and containing, as an additive improving the viscosity index, a mixture of at least two different polymer species, each of said polymer species being composed of monomers selected from the group consisting of

Shear stable multirange oils having an improved viscosity index

What is disclosed are the method of making a lubricating-oil additive which improves the viscosity index and has a dispersing and detergent action, which method comprises graft copolymerizing, onto an oil-soluble base polymer, from 0.5 to 10 parts of a polymerizable lactam together with 0.1 to 3 parts of a polymerizable N-heterocyclic compound, said parts being by weight of said base polymer, and the lubricating-oil additives so produced.

Process for graft copolymerization

What is disclosed is a concentrated polymer emulsion useful as a lubricating oil additive for improving the viscosity index thereof, said emulsion comprising: (1) a dispersed phase of an olefinic copolymer having a molecular weight complementary with respect to the thickening effect desired; (2) a dispersing phase of a polymer predominantly comprising at least one member selected from the group consisting of acrylate ester and methacrylate ester monomers; (3) a vehicle which is a good solvent for the esters in said dispersing phase and a substantially less good solvent for the olefinic copolymer by virtue of the esters dissolved in said vehicle; and (4) an emulsifier, stabilizing phase distribution, which is a member selected from the group consisting of graft copolymers and block copolymers formed from olefinic monomers and at least one member selected from the group consisting of acrylate ester and methacrylate ester monomers.

What is disclosed are methods for making polymer-in-oil solutions, useful for improving the viscosity-temperature relationship and low-temperature properties of lubricating oils when added thereto, which methods comprise polymerizing a methacrylic acid ester of an alcohol having 8 to 18 carbon atoms onto a polyolefin polymer of an olefinic hydrocarbon monomer having 2 to 4 carbon atoms in an oil solution of the polyolefin and ester monomers, then adding further polyolefin polymer to the solution and finally graft copolymerizing a polymerizable heterocyclic compound having a basic nitrogen atom in the ring thereof onto the resulting mixed polymers as backbone polymers or, in the alternative, separately graft copolymerizing a polymerizable heterocyclic compound having a basic nitrogen atom in the ring thereof onto a first backbone polymer which is itself a graft copolymer, in an oil solution, of a methacrylic acid ester of an alcohol having 8 to 18 carbon atoms on a polyolefin polymer of an olefinic hydrocarbon monomer having two to four carbon atoms and further graft copolymerizing a polymerizable heterocyclic compound having a basic nitrogen atom in the ring thereof onto a polyolefin polymer of the type described above and then combining the two graft copolymers thus formed to produce the desired polymer-in-oil solution.

A method is disclosed for making a polymer-in-oil solution, useful for improving the viscosity-temperature relationship and low-temperature properties of lubricating oils when added thereto, which method comprises a first step of polymerizing a methacrylic acid ester of an alcohol having 8 to 18 carbon atoms in a solution, in a lubricating oil, of a polyolefin polymer of an olefinic hydrocarbon monomer having 2 to 4 carbon atoms, the oil solution of said polyolefin having a viscosity of less than 15,000 centistokes at 100.degree. C., and then, in a second step, adding further polyolefin polymer of the type defined herein until the total polymer content in the oil solution is from 20 percent to 55 percent by weight of said solution and said methacrylate ester comprises from 50 percent to 80 percent of said polymer content.

Growing community of inventors

Modautal, Germany

Heinz Jost