Rhone-poulenc Chimie

Rhone-poulenc Specialites Chimiques

Rhone-poulenc Recherches

Gerard Berrod

Jean-Louis Brun

Dominique Charmot

Gilles Guerin

Francois Klinger

Eric Grillon

Robert Maurer

Bernard Vinot

Pierre Allemand

Robert Gresser

Philippe Bosc

Dicarboxylic acids, e.g., adipic acid, are prepared by reactively distilling and hydrolyzing admixture of a C.sub.1 -C.sub.4 alkyl aliphatic dicarboxylate and water, e.g., dimethyl adipate/water admixture, in liquid phase, in a distillation column, the lower end of which distillation column being charged with a gel of a crosslinked styrene/divinylbenzene resin bearing sulfonic acid substituents, the amount by weight of divinylbenzene comprising such resin ranging from 1% to 12% based on the total weight thereof and such resin having an exchange capacity of from 3 to 6.5 milliequivalents H.sup.+ /gram of dry resin, and including introducing the dicarboxylate/water admixture into the middle region of the column, withdrawing dicarboxylic acid from the base thereof and overhead distilling the alcohol of hydrolysis.

Hydrolysis of alkyl dicarboxylates

Antisoiling and anti-redeposition latices which are usable in the aqueous washing of textile materials, consisting either of copolymers of vinyl acetate with unsaturated carboxylic acids, optionally grafted with sufonic polyesters, or of (meth)acrylic/unsaturated carboxylic acid copolymers grafted with polyester sulfonates.

Antisoiling and anti-redeposition latices for the aqueous washing of

The invention provides concentrated suspensions of high molecular weight water soluble polymers comprising a high molecular weight water soluble polymer, a nonpolymer solvating organic diluent, a swelling agent and a low molecular weight polymer adjuvant, soluble in water and having functional carboxylic acid (or salt) groups thereon and methods for preparing same and the use thereof in the preparation of dilute aqueous thickening solutions suitable for use in various industrial applications, including the petroleum industry and, in particular, the secondary recovery of petroleum from underground well deposits in oil fields.

Concentrated suspensions of water soluble polymers

Stable, gel-forming aqueous microemulsions, well adopted for the reversible stabilization or plugging of soil/rock formations, e.g., subterranean well formations, are comprised of (i) an aqueous solution of a water-soluble alkali metal silicate, (ii) a gelling reagent therefor, and (iii) at least one surface active agent.

Gel-forming aqueous microemulsions for soil stabilization

Porous, subterranean oil bearing formations penetrated by at least one wellbore are temporarily and reversibly plugged/sealed, by injecting therein a solution of an alkali metal silicate and a gelling agent therefor, permitting said alkali metal silicate and said gelling agent to harden into a relatively impermeable gel, maintaining said gel for period of plugging/sealing time desired, and thence disintegrating said relatively impermeable gel to substantially restore the initial porosity of said formation.

Growing community of inventors

Villeurbanne, France

Gerard Berrod