Showing papers on "Acrylic acid published in 1987"

Method of reducing fluid loss in cement compositions which may contain substantial salt concentrations

Abstract: Cementing compositions having improved fluid loss capabilities for use in oil, gas, water and other well cementing operations are disclosed. Such compositions are comprised of water, hydraulic cement and a fluid-loss additive comprising a graft polymer comprised of a backbone of lignin, lignite, derivatized cellulose and various synthetic polymers selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polypropylene oxide and polyethyleneimine. The grafted pendant groups comprise at least one member selected from the group of homopolymers, copolymers and terpolymers of 2-acrylamido-2-methylpropanesulfonic acid, acrylonitrile, N,N-dimethylacrylamide, acrylic acid, N,N-dialkylaminoethylmethacrylate and their salts. The backbone comprises from about 5 to about 95 percent by weight of the graft polymer, and the pendant groups can comprise from about 5 to about 95 percent by weight of the graft polymer.

Batchwise preparation of crosslinked, finely divided polymers

Abstract: Crosslinked, finely divided, water-absorbing polymers are prepared in a batchwise process by copolymerization of 100 parts by weight of a monomer mixture of acrylic acid or methacrylic acid, each of which is neutralized with from 0 to 100 mol% of an alkali metal or ammonium base,or acrylamide, methacrylamide or N-vinylpyrrolidone with, as a crosslinking agent, from 0.01 to 5 parts by weight of a monomer containing two or more ethylenically unsaturated double bonds in 20-80% by weight aqueous solution in the presence of an initiator in a multistage procedure in a batchwise mixing apparatus wih constant thorough mixing in all stages, in the first stage the aqueous monomer solution being copolymerized at from 45° to 95° C. and under from 0.1 to 0.8 bar with removal of some of the water by distillation, in the second stage the copolymerization being completed at from 100° to 170° C. under a pressure of up to 8 bar, and in the third stage the water content of the resulting finely divided copolymer being decreased to 0.5-10% by weight under reduced pressure.

Anhydrous diluents for the propylene oxidation reaction to acrolein and acrolein oxidation to acrylic acid

Abstract: The processes for oxidation of propylene to acrolein and the oxidation of propylene to acrylic acid in two stages with acrolein as an intermediate are improved by use of essentially inert essentially anhydrous diluent gases to replace steam in the reaction streams. In particular, the use of essentially inert essentially anhydrous diluents which raise the composite heat capacity of the diluent gaas mixture to at least about 6.5 calories/(gram-mole) (°C.) will improve selectivity to desired products and will reduce both the waste water load on the system and by-product formation.

Electrically-conductive pressure-sensitive adhesive and biomedical electrodes

Abstract: An electrically-conductive, pressure-sensitive adhesive composition having a polymeric matrix comprised of copolymers of hydrogen bond donating monomer (for example acrylic acid) and hydrogen bond accepting monomers (for example N-vinylpyrrolidone) is disclosed. The polymeric matrix is homogeneously mixed with an electrically-­conductive plasticizing solution comprised of from 0% to 98% by weight water-soluble, polar organic compound (for example glycerol), 2% to 100% by weight water, and 0 to 12% by weight water-soluble salt. The composition contains from about 12% to 50% by weight non-volatile copolymer matrix and the hydrogen bond donating sites on the copolymer matrix are froma bout 5% to about 95% neutralized. Free radical polymerization methods of making the composition and biomedical electrodes incorporating the composition are also described.

Complex formation between poly(acrylic acid) and pyrene-labeled polyethylene glycol in aqueous solution

Abstract: Formation d'excimeres inter- et intramoleculaires entre les groupes pyrenes fixes aux deux extremites de la chaine de polyoxyde d'ethylene, utilisee pour analyser le complexe

Hair products containing dimethyl diallyl ammonium chloride/acrylic acid-type polymer

Abstract: This invention relates to improved hair products which contain dialkyl diallyl ammonium chloride/acrylic acid-type polymers. These polymers provide exceptional conditioning properties to hair products such as shampoos, conditioners, rinses, bleaches, hair dyes and hair sprays.

Synthetic ventures in pseudo-sugar chemistry

Abstract: Pseudo-sugar is a compound in which a ring-oxygen of a pyranoid sugar is replaced by a methylene group, and there are 32 theoretically possible stereoisomers in the pseudo-sugar family. All the predicted 16 DL-forms have been synthesized, as well as 9 enantiomers. The most accessible starting material for a synthesis of pseudo-sugars is endo-7-oxabicyclo[2.2.l]hept-5-ene-2-carboxylic acid which is obtained by the DielsAlder reaction of furan and acrylic acid. Recently, it has been found that some pseudo-sugars are almost equally sweet as their respective true sugars. INTRODUCTION In the last two decades, several biologically active branched-chain cyclitols and their erivatives have been found in Nature, such as (+)-(l,2,3/4,5)-tetrahydroxy-l-cyclohexanemethanol (1) (ref. 1), validamycin antibiotics (2) (ref. 2), glucosidase-inhibitors: acarbose (ref. 3), trestatins (ref. 4), adiposins (ref. 5) and oligostatins (refs. 6, 7). Since their common component, hydroxymethyl-cyclohexanetetrol or its amino derivative, is structurally closely related to a true sugar, this compound has been designated as a pseudosugar or a pseudo-amino sugar. Thus, the pseudo-sugar is a name of a class of compounds in which a ring-oxygen of a pyranoid sugar is replaced by a methylene group.

Catalyst for dehydration of lactic acid to acrylic acid

Abstract: A process for producing an acidic dehydration catalyst to convert lactic acid to acrylic acid. The process comprises impregnating an inert metal oxide carrier with a phosphate salt and buffering the impregnated carrier with a base to a pH sufficient to provide the effective dehydration catalyst.

Superabsorbent polymeric compositions and process for producing the same

Abstract: Superabsorbent polymeric compositions are prepared from monomer including acrylic acid and an effective amount of a second hydrophilic monomer, which can be a soluble salt of beta-acryloxypropionic acid. Preferably, the pH of the aqueous monomer solution is adjusted to substantially exclude free acid, and the aqueous monomer solution is coated onto a heated surface to both polymerize the monomer and dry the resulting hydrogel. Free acid thermal degradation products are avoided and the superabsorbent product has greater absorption capacity than acrylate homopolymer.

Water‐ethanol separation by pervaporation through plasma graft polymerized membranes

Abstract: Water-ethanol permselective membranes were prepared through plasma graft polymerization of acrylic acid, methacrylic acid, and acrylamide onto porous polypropylene film In these membranes, the functions of permseparation and mechanical properties are shared respectively to the graft polymer layer and the substrate film Higher permselectivity of water is achieved with the ionization of the acrylic acid and the methacrylic acid-grafted membranes Permselectivity is dependent on the degree of grafting, and it is necessary to fill the pores of substrate film with graft polymers Permseparation of water was investigated with respect to the feed ethanol concentration and also to the temperature dependence

Method for reducing residual acrylic acid in acrylic acid polymer gels

Abstract: A method for reducing the residual acrylic acid present in water-insoluble polyacrylic acid water absorbent gel polymers which comprises treating these polymers with at least 0.5 mole of either amino acid cysteine or lysine per mole of acrylic acid present in said waters for at least 15 minutes at a temperature of at least 80° C.

Excimer fluorescence determination of solid-liquid interfacial pyrene-labeled poly(acrylic acid) conformations

Abstract: The conformations of a pyrene-labeled poly(acrylic acid) adsorbed at the water-solid interface were studied by using fluorescence of the pyrene excimer as an indication of the presence or absence of polymer strand coiling. It is found that adsorption from aqueous solution onto positively charged alumina is rapid and that the conformation of the polymer at the surface reflects the state of the polymer in solution prior to adsorption. In the case of high pH adsorption, the extended polymer (low excimer contribution) bound to the surface is not affected by lowering the pH of the solution. In contrast, when the polymer is initially adsorbed in coiled form (low pH), raising the pH of the solution partially leads to extension of the polymer on the surface. Binding to positively charged silica leads to a more extended conformation of the polymer which is relatively unaffected by the pH of the solution; that is, adsorption at high pH followed by a decrease in pH does not change the relative amount of excimer present.

Novel macromonomer compositions

Abstract: Novel compositions of homopolymers and copolymers containing an olefinic polymerizable end group wherein the monomeric units comprise methacrylate, acrylate, acrylic acid, styrene, vinyl esters, acrylonitrile, methacrylonitrile, vinyl halides, vinylidene halides, substituted butadienes, ethylene-sulfonic acid derivatives, acrylamide derivatives, methacrylamide derivatives, and other monomers, and mixtures thereof are disclosed.

Titration of poly(acrylic acid) and poly(methacrylic acid) in methanol

Abstract: Relation entre la constante de dissociation du polyacide et son degre de neutralisation par le methylate de lithium

Dishwashing compositions containing water-soluble polymers

Abstract: Dishwashing compositions based on mixtures of (a) at least 5% by weight of at least one ammonium or alkali metal carbonate or of one ammonium or alkali metal sulphate, (b) at least 35% by weight of sodium silicate and (c) 0.5 to 20% by weight of water-soluble copolymers which have a molecular weight of 500 to 8000 and which contain, as copolymerised units, (1) 50 to 95% by weight of acrylic acid and/or methacrylic acid, (2) 0 to 25% by weight of acrylamide and/or methacrylamide and (3) 5 to 25% by weight of 2-acrylamido-2-methylpropanesulphonic acid, vinylsulphonic acid, styrenesulphonic acid, 3-sulphopropyl acrylate, 3-sulphopropyl methacrylate, mixtures thereof and/or alkali metal or ammonium salts thereof, with the proviso that the total of the amounts in % by weight under (1) to (3) is always 100.

Methacrylic-acid derivatives containing urethane groups

Abstract: The new (meth)acrylic acid derivatives containing urethane groups can be prepared by reaction of a (meth)acrylic acid ester with diisocyanates and subsequent reaction with polyols. The compounds can be used for dental materials.

Phenolic compound and stabilizer containing said compound as active component for butadiene based polymer

Abstract: NEW MATERIAL:2,4-Di-tert-amyl-6-[1-(3,5-di-tert-amyl-2-hydroxyphenyl)ethyl ]phenyl acrylate expressed by the formula. USE:A stabilizer for butadiene based polymers having excellent solubility in solvents. The amount thereof blended is 0.05-2 pts.wt., preferably 0.1-1 pt.wt. based on 100 pts.wt. butadiene based polymers. PREPARATION:2,2'-Ethylidenebis(4,6-di-tert-amylphenol) is subjected to esterification reaction with acrylic acid or an acid derivative, such as acryloyl chloride or bromide or acrylic anhydride, to afford the aimed compound expressed by the formula.

Acrylate hot melt adhesive containing zinc carboxylate

Abstract: An improved hot melt pressure sensitive adhesive composition comprises copolymerized monomeric acrylate or methacrylate ester of a non-tertiary alcohol, polar monomer such as acrylic acid, 2-polystyrylethyl methacrylate macromolecular monomer and sufficient zinc carboxylate to endow the composition with improved melt flow properties and cohesive strength. The invention also provides adhesive coated sheet materials comprising the adhesive composition coated onto a flexible sheet.

Pressure sensitive adhesive film with barrier layer

Abstract: A pressure sensitive adhesive film reducible in the adhesive force by the application thereto of the ultraviolet light which comprises: (a) a base film permeable to the ultraviolet light; and (b) a layer of a pressure sensitive adhesive formed on one side of the base film, the adhesive comprising: (i) at least one elastic polymer selected from the group consisting of a polymer mainly composed of acrylic acid ester copolymers and a saturated copolyester mainly composed of dibasic carboxylic acids and dihydroxy alcohols; (ii) an ultraviolet light polymerizable acrylic acid ester having not less than two acryloyl or methacryloyl groups in the molecule in amounts of about 15-200 parts by weight in relation to 100 parts by weight of the elastic polymer; and (iii) a photopolymerization initiator in amounts sufficent to induce the photopolymerization of the ultraviolet light polymerizable acrylic acid ester; The film is especially suitable for use as a dicing film in dicing a semiconductor wafer to dices in which the wafer is fixed on the film with a relatively large adhesive force and thereafter the film is irradiated by the ultraviolet light from the other side thereof to substantially reduce the adhesive force of the film so that the dice is loosely adhered onto the film.

High viscosity, neutral polyolesters

Abstract: Synthetic polyol esters with lubricating oil properties based on substantially neutral esterification products of a polyhydric alcohol with selected monocarboxylic acids and, optionally, polybasic carboxylic acids, wherein the polyfunctional alcohol component is dipentaerythritol which is esterified with I--branched C 8 -C 16 fatty acids (class A acids) or with II--mixtures of linear C 8 -C 14 fatty acids (class B acids) with branched fatty acids of class A and, optionally, limited quantities of polybasic carboxylic acids of the following classes C, D and/or E incorporated in the polyester molecular by condensation: class C acids: di- and/or tricarboxylic acids in the range from C 6 to C 54 class D acids: difunctional fatty acids which have been obtained by addition of acrylic acid onto the double bonds of oleic acid, linoleic acid and/or linolenic acid class E acids: aromatic and/or paraffinic, cyclic polycarboxylic acids containing from 2 to 6 acid functions.

Water-absorbent acrylic acid polymer gels

Abstract: Improved acrylic acid absorbency resins are made utilizing a chain transfer agent during the polymerization process.

A process for the preparation of copolymers

Abstract: Process for the preparation of copolymers from acrylamide and acrylic or methacrylic acid, wherein to prepare 100 parts by weight of the copolymer, (A) 10-90 parts by weight of acrylamide, (B) 90-100 parts by weight of acrylic acid and/or methacrylic acid or of a salt thereof, (C) 0-40 parts by weight of another copolymerizable monomer and (D) 0-5 parts by weight of a copolymerizable crosslinking agent which has two or more olefinic double bonds are polymerized in an alcohol having 1-4 carbon atoms by precipitation polymerization such that 10-90% by weight of the alcohol, 10-90% by weight of the total amount of monomers (A), (B) and (C) together with 100% by weight of the crosslinker substance are initially mixed, polymerization is started with 10-100% by weight of the initiator and then the remainder of the solvent, monomers, crosslinking agent and initiator to make up to 100% is metered in, as individual components or as a mixture, after the polymerization has started.

Latex compositions useful as binders in composite board having dimensional stability and strength

Abstract: Polymeric latexes with a relatively high Tg such as: styrene, butadiene and acrylic acid; or methyl methacrylate, ethyl acrylate and fumaric acid can be used in whole or in part as a binder to produce strong composite board that will not sag substantially under conditions of high temperature and humidity.