Abstract: An alkenyl anhydride or polyalkenylsuccinic anhydride is prepared without forming resins, by an ene-synthesis reaction between an olefin or a polyolefin and a maleic anhydride, optionally substituted by one or two methyl groups, in an aromatic solvent that is selected from toluene and xylenes, whereby said anhydride is used at a ratio of 30 to 60% by weight relative to the reaction medium.More particularly, polyisobutenylsuccinic anhydrides which can be used to form, by reaction with polyethylene polyamines, compositions that contain polyisobutenylsuccinimides, used as detergent additives for motor fuels or as ashless dispersants for motor oils, are produced.

Abstract: A simplified process for preparation of an alkenylsuccinimide or a polyalkenylsuccinimide is described, characterized in that it comprises successively: a stage (a) in which an alkenylsuccinic anhydride or a polyalkenylsuccinic anhydride is prepared by bringing about an ene-synthesis reaction between at least one olefin or one polyolefin and at least one unsaturated dicarboxylic anhydride that is selected from maleic anhydride and the maleic anhydrides that are substituted by 1 or 2 methyl groups, characterized in that said reaction is carried out within at least one aromatic solvent that is selected from toluene and the xylenes that are used at a ratio of between 30 to 70% by weight of the reaction mixture and in which a fraction of said unsaturated dicarboxylic anhydride does not react with said olefin or polyolefin; a stage (b) in which the product of stage (a) that contains unsaturated, unreacted dicarboxylic anhydride is reacted with at least one alcohol or an amine; and a stage (c) in which the product

Abstract: Chlorine-free polyfunctional polyisobutenes are described that can be modified by amines, alcohols and/or amino alcohols to result in additives that can be used in the petroleum field in particular in fuels and engine lubricants.They are prepared by radical terpolymerization of isobutene, maleic anhydride and polyisobutene having an average content of "exo" end double bonds of at least 50%.

Abstract: New dispersing additive compositions for lubricating oils, an object of the invention, have an improved efficiency.Said compositions may be either (1) the products obtained by reacting alkenylsuccinimides with aromatic dianhydrides, or (2) the products obtained by reacting alkenylsuccinimides with an anhydride or a dianhydride of mono- or poly-carboxylic aliphatic, alicyclic or aromatic acid of low molecular weight, the obtained product being then reacted with at least one organic compound having several hydroxyl and/or amine groups.These dispersing additive compositions may be added to lubricating oils in a proportion, for example, from 0.1 to 20% by weight.

Abstract: Stable suspension of a water-soluble polymer comprising solid particles of this water-soluble polymer in a liquid hydrocarbon medium which also comprises a thickening agent selected from the alkali or alkaline-earth metal salts of fatty acids having 6-33 carbon atoms. The resultant suspensions are stable and dissolve easily when dispersed in water; they can be used in enhanced oil recovery. They may also contain minor proportions of water and/or of C.sub.1 -C.sub.12 monoalcohols or C.sub.2 -C.sub.12 diols.

Abstract: A solid composition of coated water-soluble polymer is made from 80 to 250 parts b.w. of solid particles of at least one water-soluble polymer coated with 100 parts b.w. of at least one paraffinic product solid at room temperature and whose melting point is preferably from 40.degree. to 90.degree. C. The solid composition is made by dispersing particles of the water-soluble polymer in the molten paraffinic product and then cooling down to room temperature.

Abstract: Stable suspension of a water-soluble polymer comprising solid particles of this water-soluble polymer in a liquid hydrocarbon medium which also comprises a thickening agent selected from the alkali or alkaline-earth metal salts of fatty acids having from 6-33 carbon atoms. The resultant suspensions are stable and dissolve easily when dispersed in water; they can be used in enhanced oil recovery.

Abstract: Copolymers comprising acrylic ester units, dicarboxylic compounds units and diisobutylene units and whose average molecular weight by number is from 500 to 250,000 are useful for improving the cold-flow properties of lube oils and other hydrocarbon oils such as diesel oil, heavy fuel oil, residual fuel oil and crude petroleum.

Abstract: Syntactic foam compositions are manufactured by heat-curing, in the presence of a free radical generator, a mixture comprising a resin and hollow spheres; the resin consists of(a) 10 to 100% of polybutadiene with 20-95% 1,2 units, 5-60% thereof being in a carbocyclic cyclized form, its number average molecular weight being at most 100,000;(b) 0 to 90% of polybutadiene with 40-98% 1, 2 units and 2-60% 1, 4 units, its number average molecular weight being at most 100,000; and(c) 0 to 90% of a polymerizable liquid vinyl monomer.

Abstract: A process for the preparation of a stable diploid of Candida lipolytica which comprises (a) in a first stage, separately cultivating two haploid strains of Candida lipolytica of opposed sign in a medium rich in assimilable carbon nutrient; (b) in a second stage, cultivating the two resultant strains together in a medium poor in assimilable carbon nutrient; and (c) in a third stage, after the appearance of diploid colonies, treating them with a mutagenic agent to stabilize them. The invention also comprises a process for the preparation of .alpha.-ketoglutaric acid which comprises cultivating a diploid strain obtained by crossing two Candida lipolytica haploid strains of opposite sign in a medium containing, as source of assimilable carbon, at least one hydrocarbon.