Abstract: Acrylic acid or other unsaturated carboxylic acid is made by hydrolysing the corresponding nitrile in the presence of excess sulphuric acid to form amide sulphate, adding amide in an amount such that the total amount of amide and nitrile fed to the process is greater than 1 mole per mole sulphuric acid, hydrolysing the amide sulphate and amide to the desired acid and separating the acid from the sulphate by-products.

Abstract: Sulfonated polymers and copolymers are used as thinners in aqueous drilling or packer fluids. The sulfonated polymer has polydispersity below 2 and has a low solution viscosity. It is generally a copolymer of beta-arylamidoalkane sulfonate or allyl sulfonate or other aliphatic sulfonate with an ethylenically unsaturated carboxylic acid, generally acrylic acid.

Abstract: When flocculating an aqueous suspension of suspended solids using a high molecular weight synthetic polymeric flocculant the shear stability of the flocs is increased if the polymeric material includes polymeric particles of below 10 .mu.m dry size. The flocculated solids can therefore be subjected to shear without increasing the amount of discrete suspended solids in the aqueous medium and generally they are suspended to shear by shearing the aqueous medium containing them, either before dewatering, generally on a centrifuge, piston press or belt press, or by continuously agitating them, for instance in a chemical reaction medium. The polymeric material is generally formed by mixing into water polymeric particles made by reverse phase or emulsion polymerization in the presence of added cross linking agent. Alternatively particles insolubilized by insoluble monomer may be used. A reverse phase dispersion of water soluble polymer may be used if the particles remain undissolved, e.g.

Abstract: Water soluble, substantially linear, polymers having single point intrinsic viscosity above about 3 are formed from an ethylenically unsaturated monomer that includes a group --B.sub.n A.sub.m R where A is propoxy or butoxy, B is ethoxy, n is zero or an integer of 2 to 100 and m is zero or an integer less than n, and R is a hydrophobic group of at least 8 carbon atoms and comonomer selected from non-ionic monomers and dialkylamino alkyl (meth) -acrylates or -acrylamides wherein at least one of the monomers is tertiary amine acid addition or quaternary ammonium salt. The resultant water soluble, high molecular weight, cationic polymers are useful as flocculants and as viscosifiers of aqueous acid solutions such as downhole acid stimulation fluids.

Abstract: When making an a amide by hydrolysis of a nitrile in an aqueous medium containing a Raney copper catalyst, the yield of amide can be increased and the yield of impurities can be decreased by including vanadium metal in the catalyst. The vanadium may be present as Raney vanadium often as an alloy in the Raney copper.

Abstract: A substantially dry, particulate polyacrylamide composition having reduced acrylamide monomer content is made by mixing amidase with coarse aqueous gel polymer particles, absorbing the amidase into the particles and subsequently drying the particles.

Abstract: A particulate mass that can be dusty but is generally sticky, due to the presence of water, is coverted to an apparently dry, non-dusty granular material by polymerizing a polymerizable material within the mass and breaking the mass down to the desired granular form after the polymerization has gone sufficiently far that the mass is substantially non-sticky but before the polymerization is completed.

Abstract: Polymers are made by polymerization of an ionic monomer such as methacrylic acid or dialkylaminoalkyl (meth)-acrylate or -acrylamide and/or a substantially non-ionic monomer, optionally a cross linking agent, and an allyl ether of the formula CH.sub.2 .dbd.CR'CH.sub.2 OA.sub.m B.sub.n A.sub.p R where R' is hydrogen or methyl, A is propyleneoxy or butyleneoxy, B is ethyleneoxy, n is zero or an integer, m and p are zero or an integer less than n, and R is a hydrophobic group of at least 8 carbon atoms. The polymers are preferably made by oil in water emulsion polymerization. They can be used as thickeners particularly in environments containing surfactant and/or electrolyte, including especially emulsion paints, print pastes, alkaline liquors and acidic liquors.

Abstract: A wet filter cake of coal fines or other inorganic particulate material is converted to a crumbly mass by blending with water absorbent polymer particles.

Abstract: 2-acrylamido 2-methyl propane sulphonic acid and other acrylamido-alkane sulphonic acids are made by reacting a compound such as t-butanol, t-butyl acetate or t-butyl methyl ester with a sulphonating agent in the absence of water, and then with a nitrile and water.

Abstract: Water absorbent, water insoluble, cross linked polymer fibre or film can be made by dry extrusion of a solution of a substantially linear polymer formed from a water soluble blend of monoethylenically unsaturated monomers comprising a plasticizing monomer, evaporating the solvent and forming polymeric fibre or film plasticized by an external plasticizer, stretching the fibre or film while the external plasticizer remains in the fibre or film, and then cross linking the polymer.

Abstract: A concentrate composition, that can be diluted with water to form an aqueous size for cellulosic fibres, comprises a substantially anhydrous dispersion of polyelectrolyte particles in a non-aqueous liquid comprising a reactive size, and is made by forming a dispersion in a hydrophobic liquid of the polyelectrolyte particles while they are swollen by water, azeotroping the dispersion and adding the size to the hydrophoboic liquid. If the size is a liquid size, the hydrophobic liquid may be removed from the composition. The dispersion of swollen polyelectrolyte particles in the hydrophobic liquid can be amde by dispersing a solution of polyelectrolyte in the liquid but is preferably made by reverse phase polymerization.

Abstract: A homogenous blend is formed of different water soluble polymer types, for instance of particular addition and condensation polymers, by forming one of the polymers from its monomeric starting material by polymerisation in a solution of the other polyer. The resultant solution has a concentration of above 10% but is homogenous. It can be used as a bulk solution or can be dried to powder or can be present as a reverse phase dispersion.

Abstract: When making an unsaturated amide by hydrolysis of an unsaturated nitrile in the presence of a catalyst such as Raney copper and an oxidizing agent such as copper nitrate, by-product formation is reduced by including a reagent selected from reducing agents and acids that are substantially non-oxidizing relative to the said oxidizing agent. The preferred reagents are acidic buffers, especially acetic acid and copper acetate. Washing with such a buffer a Raney catalyst or other catalyst that is to be used for catalyzing the hydrolysis of an unsaturated nitrile to an unsaturated amide reduces the temperature surge that otherwise occurs upon addition of the catalyst to the reaction mixture.

Abstract: Measurement of the ionic value X of a solution of a polyelectrolyte after shearing, for instance by a rotating blade, and/or measurement of the ionic value Y of a solution of polyelectrolyte before shearing, and especially the difference between t he values X and Y, gives a useful indication of the degree of cross linking of the polyelectrolyte and so can be utilized to control the manufacture of the polyelectrolyte, for instance drying conditions, or the storage or use of the polyelectrolyte, for instance its suitability or dosage in a flocculation process.

Abstract: A dispersing agent for particles in aqueous media comprises a copolymer formed from ethyleneically unsaturated monomers including a water-soluble monomer and a monomer carying a pendant group A.sub.m B.sub.n A.sub.p R in which B is ethyleneoxy and n is at least 2, m and p are each generally 0 and R is a hydrophobic group, generally a C.sub.12-18 alkyl group or alkaryl group. The polymers generally have molecular weights in the range 500-100,000. The dispersants are particularly useful for suspending hydrophobic particles in aqueous media, for example to produce coal slurries, or to suspend hydrophilic particles in aqueous media having high electrolyte concentrations, for example for producing paints and, particularly, drilling muds formed in sea water.

Abstract: A Mannich base of a high molecular weight acrylamide polymer can be made by reacting, in aqueous solution, the polymer with a Mannich base of a low molecular weight compound such as urea. A composition of the polymer and the Mannich base is preferably substantially non-aqueous.

Abstract: A water soluble or swellable polymer gel is dispersed into a liquid phase to form a fluid composition and is worked while in that composition. The liquid phase is an aqueous solution of an equilibrating agent that substantially prevents aggregation of the particles or dissolution of the polymer during the working. The working may be, for instance, milling, extraction of impurities, extraction of water, transportation or chemical modification. Preferred equilibrating agents are sodium polyacrylate and polydiallyl dimethyl ammonium chloride.

Abstract: A cross linked high molecular weight polymer formed from a water soluble monomer or blend of monomers and which has IV and/or solubility and/or rheology properties indicating that it would be unsuitable for use as a flocculant can be used as a flocculant after shearing the polymeric material. The shearing may be applied to the polymeric material before addition to the suspension that is to be flocculated or can be applied to the suspensionthat is being flocculated. The shearing increases the intrinsic viscosity of the polymeric material and can improve its rheology and solubility. The polymeric material must be of high molecular weight.

Abstract: The combination of adhesion and rheology properties of aqueous adhesives the adhesive component of which is a water soluble or water swellable polymeric material can be improved by copolymerizing the monomers from which the polymeric material is obtained with an ethylenically unsaturated monomer that includes a pendant group --A.sub.m B.sub.n A.sub.p R where B is ethoxy, n is at least 2, A is propoxy or butoxy, m and p are each less than n and are preferably zero, and R is a hydrophobic group.