Abstract: Preparation process for glyoxylic acid in which glyoxal is subjected to a heterogeneous catalytic oxidation in an aqueous medium by oxygen in the presence of catalytic quantities of platinum.

Abstract: Glycerol derivatives of general formula (I) ##STR1## in which R=allyl, methylallyl, acryloyl or methacryloyl, R.sub.1 =R.sub.2 =glyoxyloyl, R.sub.1, R.sub.2 =H, glyoxyloyl; their preparation process, their use as cross-linking agnets and cross-linking or cross-linkable compositions containing them. These compounds are useful as crosslinking agents for woven and non-woven fibrous mats and textiles.

Abstract: Hydrophilic, powdered superabsorbents which are insoluble in water, containing by weight, in the dry state, in combination, from 1 to 45% of colloidal silica with an average diameter of non-agglomerated particles of about 9 to about 50 nanometers and 99 to 55% of a cross-linked polymer based on free acrylic acid, partially or totally salified by a sodium or potassium, preparation process and use notably for the absorption of aqueous fluids.

Abstract: Continuous manufacturing process for an aqueous solution of glyoxylic acid by nitric oxidation of an aqueous solution of glyoxal carried out in the presence of hydrochloric acid in which the oxidation is effected continuously using 0.80.+-.0.2 mole of nitric acid and 0.70.+-.0.05 mole of hydrochloric acid per mole of glyoxal in a reaction medium having a concentration by weight between 5 and 6% of hydrochloric acid and higher than 10% of nitric acid.

Abstract: Process for obtaining by sol-gel route refractory metal oxides based on silica in which a monolithic gel is prepared, in an aqueous medium, at a temperature of less than 60.degree. C., by leaving at rest an aqueous sol obtained by simple mixing in stoichiometric quantities of an aqueous sol of silicic acid and of one or more aqueous solutions of a water-soluble salt of one or more other constitutive metals of these oxides, then the monolithic gel obtained is calcined at a temperature of less than 1000.degree. C. after it has been dried at a temperature of less than 150.degree. C.

Abstract: Hydrophilic polymer, as microbeads insoluble in water, based on acrylic acid and an alkali metal acrylate constituted by an acrylic acid-potassium acrylate copolymer, cross-linked with 100 ppm to 3,000 ppm relative to the total weight of monomers of one or more cross-linking agents chosen from the group constituted by the products of general formula I: ##STR1## A=a bivalent radical derived from a C.sub.3 -C.sub.6 alkane presenting an absorption capacity for a salty physiological solution of 30 to 70 g per gram and from 10 to 35 g per gram under pressure, preparation process and use notably in articles of hygiene.

Abstract: Preparation process for piperonal by decarboxylating oxidation of 3,4-methylenedioxy mandelic acid by nitric acid in aqueous medium in the presence of hydrochloric acid.

Abstract: Glycerol derivatives of general formula (I)CH.sub.2 --ORCH--OR.sub.1 (I)CH.sub.2 --OR.sub.2in which R=allyl, methylallyl, acryloyl or methacryloyl, R.sub.1 =R.sub.2 =glyoxyloyl, R.sub.1, R.sub.2 =H, glyoxyloyl; their preparation process, their use as cross-linking agents and cross-linking or cross-linkable compositions containing them.Application in the textile or paper industry.

Abstract: The invention relates to the preparation of glyoxylic acid by oxidizing an aqueous solution of glyoxal having a pH less than 1 with molecular oxygen in the presence of nitrogen monoxide as a catalyst.This process allows the practically total conversion of the starting glyoxal with a good yield of glyoxylic acid.

Abstract: The invention concerns new polyfunctional ethylenic monomers of the general formula (I): ##STR1## where R.sub.1 and R.sub.2 each represent --CHR.sub.3 R.sub.4 where R.sub.3 and R.sub.4 may be identical or different and represent H or an alkyl, alkenyl or aralkyl group. R.sub.1 and R.sub.2 may, alternatively, together form a radical --CH.sub.2 --(CR.sub.5 R.sub.6).sub.n --CHR.sub.7 where n=0 or 1 and R.sub.5, R.sub.6 and R.sub.7 may be identical or different and represent H or CH.sub.3.Particular monomers are:2-cyano-4,4-dimethoxy-3-hydroxy-1-butene;2-cyano-4,4-dibutoxy-3-hydroxy-1-butene.

Abstract: Hydrophilic polymer, as microbeads insoluble in water, based on acrylic acid and an alkali metal acrylate constituted by an acrylic acid - potassium acrylate copolymer, cross-linked with 100 ppm to 3,000 ppm relative to the total weight of monomers of one or more cross-linking agents chosen from the group constituted by the products of general formula I: ##STR1## A=a bivalent radical derived from a C.sub.3 -C.sub.6 alkane presenting an absorption capacity for a salty physiological solution of 30 to 70 g per gram and from 10 to 35 g per gram under pressure, preparation process and use notably in articles of hygiene.

Abstract: The invention provides an improved process for the manufacture of alkyl pyruvates having general formula (I):CH.sub.3 --CO--COOR (I)where R represents a C.sub.1 to C.sub.8 alkyl radical, by controlled oxidation of the corresponding alkyl lactate.The process is characterized in that the controlled oxidation is carried out using an aqueous hydrogen peroxide solution in the presence of catalytic quantities of bromium.

Abstract: The invention concerns new polyfunctional ethylenic monomers of the general formula (I): ##STR1## where R=cyano, substituted or unsubstituted acyl, substituted or unsubstituted alkoxycarbonyl or substituted or unsubstituted aryloxycarbonyl; R.sub.1 and R.sub.2 each represent --CHR.sub.3 R.sub.4 where R.sub.3 and R.sub.4 may be identical or different and represent H or an alkyl, alkenyl or aralkyl group. R.sub.1 and R.sub.2 may, alternatively, together form a radical --CH.sub.2 --(CR.sub.5 R.sub.6).sub.n --CHR.sub.7 where n=0 or 1 and R.sub.5, R.sub.6 and R.sub.7 may be identical or different and represent H or CH.sub.3.Particular monomers are: 2-cyano-4,4-dimethoxy-3-hydroxy-1-butene; 2-cyano-4,4-dibutoxy-3-hydroxy-1-butene; 4,4-dibutoxy-2-ethoxycarbonyl-3-hydroxy-1-butene; 2-butoxycarbonyl-4,4-dibutoxy-3-hydroxy-1-butene; 4,4-dimethoxy-2-hydroxythoxycarbonyl-1-butene; 4,4-dimethoxy-2-dimethylaminoethoxycarbonyl -3-hydroxy-1-butene; and 4,4-dimethoxy-2-ethoxycarbonyl-3-hydroxy-1-butene.

Abstract: This process is characterized by the fact that glyoxylic acid in aqueous solution is reacted with an excess of phenol in the presence of a tertiary amine, insoluble or slightly soluble in water and liquid at ambient temperature, in particular tributylamine or triisooctylamine, then the parahydroxymandelic acid thus obtained is salified with sodium hydroxide in aqueous solution.The reaction of the glyoxylic acid with phenol is carried out at a temperature between 15.degree. C. and 80.degree. C.

Abstract: An aqueous styrene-acrylic type polymer dispersion useful as a wet strength adhesive contains at least one copolymer consisting of 0.5 to 5% by weight of N-allylacetoacetamide monomer (A) and 99.5 to 95% by weight of a mixture of monomers (B) consisting of 90 to 99.9% by weight of styrene and of at least one monomer selected from C.sub.1 to C.sub.8 alkyl (meth)acrylates and 10 to 0.1% by weight of at least one monomer selected from acrylic acid, methacrylic acid, acrylamide and methacrylamide.

Abstract: Amino-plastic resins soluble in water of which the nitrogenous derivative is chosen from the group comprising urea, 1,3-dimethyl-urea, ethyleneurea, 4,5-dihydroxy-ethyleneurea or their mixtures and the aldehyde derivative is a mixture of from 1 to 99% by weight of glyoxal and from 99 to 1% by weight of glyoxal monoacetal of formula (RO).sub.2 CH--CHO; R=C.sub.1 -C.sub.4 alk, their ethers and their applications in particular with cellulosed fibre treatment.

Abstract: The process for preparing a novel product, pure crystalline methyl 2-acryloylamino-2-methoxyacetate, involves reacting pure crystalline, anhydrous acrylamido-glycolic acid in an anhydrous medium with methanol in the presence of hydrogen chloride. This is subsequently neutralized with an alkali metal bicarbonate, and then the mineral salts are filtered off. Finally, pure crystalline methyl 2-acryloylamino-2-methoxyacetate is obtained by taking up the concentrated reaction medium in 1,1,1-trichloroethane under vacuum.

Abstract: This new thiophenol, prepared by reduction of tertiary butyl-4-toluenesulfonyl-2-chloride with the zinc-sulphuric acid couple, can be used as a stabilizer for vinyl chloride polymers, as a chain-transfer agent and as a peptizer.

Abstract: An aqueous styrene-acrylic type polymer dispersion useful as a wet strength adhesive contains at least one copolymer consisting of 0.5 to 5% by weight of N-allylacetoacetamide monomer (A) and 99.5 to 95% by weight of a mixture of monomers (B) consisting of 90 to 99.9% by weight of styrene and of at least one monomer selected from C.sub.1 to C.sub.8 alkyl(meth)acrylates and 10 to 0.1% by weight of at least one monomer selected from acrylic acid, methacrylic acid, acrylamide and methacrylamide.

Abstract: These aqueous dispersions contain a copolymerizate containing 90 to 99% by weight of repeating units resulting from the polymerization of a mixture of monomers (a) based on 0.1 to 10% by weight of alpha,beta-ethylenic mono- and/or di-carboxylic C.sub.3 -C.sub.5 acid and/or their amides, 0 to 10% by weight of styrene and/or acrylonitrile, the remainder of the esters of (meth)acrylic acid with C.sub.1 -C.sub.12 alkanols; and 10 to 1% by weight of repeating units of general formula (I) ##STR1## where R=H or --CH.sub.3, R.sub.1 =H or C.sub.1 -C.sub.4 alkyl and R.sub.2 and R.sub.3 =C.sub.1 -C.sub.8 alkyl or a --CH.sub.2 --CR.sub.4 R.sub.5 --(CH.sub.2).sub.n --group in which n=0 or 1 and R.sub.4 and R.sub.5 =H or --CH.sub.3.