Showing papers on "Methacrylic acid published in 1984"

Developments in Polymer Degradation - 5

Abstract: 1. Degradation of Polymers of Methacrylic Acid Salts and Copolymers of these Salts with Methyl Methacrylate.- 2. Thermal Degradation Mechanisms in Condensation Polymers.- 3. Degradation and Stabilisation of Polyesters of Biological and Synthetic Origin.- 4. Degradation of Poly (methyl methacrylate) by Ionizing Radia-tion and Mechanical Forces.- 5. Mechanochemistry of Lignocellulosic Materials.- 6. Reactions of Small Radicals with Polymers during Degradation.- 7. Mechanism of Fire-retardancy in Chloroparaffin-Polymer Mixtures.

pH-Dependent complexation of poly(acrylic acid) derivatives with phospholipid vesicle membranes

Abstract: Poly(acrylic acid), poly(methacrylic acid), and poly(α-ethylacrylic acid) can be used to modify, in a pH-dependent manner, the properties of phospholipid vesicle membranes. Polymer-lipid complexation caw a decrease in the apparent cooperativity of the lipid melting transition. The "critical pH" for complexation may be controlled through variation of the chemical structure and the tacticity of the poly(carboxylic acid), It is suggested that an important driving force for complexation is provided by the formation of hydrogen bonds between un-ionized carboxyl groups of the polymer and the phosphodiester functions of the lipid surface.

Adhesive and coating composition

Abstract: A hot melt adhesive and coating composition is provided comprising a copolymer of ethylene and acrylic acid or methacrylic acid; a compatible wax and a tackifier. The copolymer characterized as having a melt flow of at least about 0.77 and an acrylic acid or methacrylic acid content such that the copolymer has an acid number ranging from about 8 to about 93.

Effects of low levels of methacrylic acid on the swelling behavior of poly(2-hydroxyethyl methacrylate)

Abstract: The effects of low levels of methacrylic acid (MAA) (less than 4 mol %) and a crosslinker (less than 0.3 mol %) on the equilibrium swelling and water content of poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels were investigated. Numerous pHEMA disks, some of which were doped with small amounts of MAA, were placed in swelling baths simulating possible urological as well as physiological conditions. Several interesting facts are reported, such as, in dilute urea (0.15M) or in alkali solution, gels containing 2% MAA are capable of swelling to 3600% their size in mild acid, saline, or distilled water, with associated water contents that range as high as 98%. Also, gels containing small amounts of MAA and finite crosslinker content can be made that are soluble in mild urea or alkali solution. The significance of this study is that gels or gel surfaces can be fabricated that are highly responsive to their environment. In addition, since the level of MAA that cause this shrink–swell behavior are well within the impurity levels of MAA found in unpurified commercial HEMA, it is conceivable that this shrink–swell behavior may have occurred in early studies of implanted pHEMA gels, thus confusing the subsequent evaluation of its performance as a biomaterial.

Method of inhibiting scaling in aqueous systems with low molecular weight copolymers

Abstract: A method for inhibiting scale formation in aqueous systems using water-soluble, low molecular weight copolymers of unsaturated aliphatic carboxylic acids is provided Copolymers formed from about 30 to about 70 weight percent acrylic acid and from about 70 to about 30 weight percent methacrylic acid, having a weight average molecular weight ranging from about 2000 to about 5000, are preferred for inhibiting the formation of common hardness ion salt scale such as calcium carbonate, calcium phosphate and barium sulfate The copolymers are hydrolytically stable and can be used effectively in high temperature applications The copolymers are also effective dispersants for suspended inorganic particulate materials, such as clay, in aqueous systems

Complexation and rate of polymerization of acrylic acid and methacrylic acid in the presence of poly(4‐vinylpyridine) in dilute methanol solution

Abstract: Nature de l'interaction entre ces monomeres et la polyvinyl-4 pyridine et effet de la PV4P sur la vitesse de polymerisation des monomeres acides en solution de methanol diluee

Production of methacrolein and methacrylic acid

Abstract: PROBLEM TO BE SOLVED: To provide a method for producing methacrolein and methacrylic acid by which the decrease of a catalytic function is prevented and the operation over a long term is made possible by carrying out a vapor phase catalytic oxidation of isobutylene or tert-butanol with molecular oxygen. SOLUTION: Isobutylene or tert-butanol is subjected to a catalytic oxidation by a complex oxide consisting essentially of molybdenum, bismuth and iron to provide the objective methacrolein and methacrylic acid in the method for producing the methacrolein and methacrylic acid. The reaction is started at a temperature lower than (T-3)°C (T°C is a boundary temperature of an activation energy of the reaction for obtaining the methacrolein and the methacrylic acid from the isobutylene by using the catalyst), continued while rising the reaction temperature according to the decrease of the catalytic activities. At least one time of activation treatment of the catalyst is carried out before the reaction temperature becomes higher than the boundary temperature. COPYRIGHT: (C)1999,JPO

Coating composition, in particular for producing a transparent topcoat of a multilayer coating, a process for producing coatings, and an article coated with a multilayer coating

Abstract: A coating composition, in particular for producing the transparent topcoat of a multilayer coating. The coating composition contains as binders two acrylic polymers, A and B, as well as aliphatic and/or cycloaliphatic polyisocyanates. Acrylic polymer A has a molecular weight of 800 to 4,000, a hydroxyl number of 80 to 180 and a glass transition temperature of below -10° C. Acrylic polymer B has a molecular weight of 3,000 to 10,000, a hydroxyl number of 40 to 120 and a glass transition temperature of -10° C. to +10° C. Whereas in acrylic polymer A the proportion of acrylic acid esters predominates, polymer B contains methacrylic acid esters as predominant monomer components.

pH-Sensitive permeability control of polymer-grafted nylon capsule membranes

Abstract: Poly(4-vinylpyridine) or poly (methacrylic acid) was grafted onto an ultrathin, porous nylon capsule membrane so that permeation across the capsule membrane of NaCl trapped in the inner aqueous phase could be reversibly controlled by ambient pH changes.

Crotonate-containing copolymers, processes for their preparation and their use as thickeners in aqueous systems and as sizing agents

Abstract: Copolymers prepared by emulsion or solution copolymerization, initiated by free radicals, of unsaturated copolymerizable monomers, the copolymers being built up from (a) 1-45% by weight of ethylenically unsaturated carboxylic acids, (b) 0.5-30% by weight of a surface-active crotonic acid ester, (c) 30-85% by weight of methacrylic acid esters or acrylic acid esters of aliphatic (C 1 -C 18 )-alcohols, (d) 0-40% by weight of other ethylenically unsaturated comonomers, (e) 0-3% by weight of polyethylenically unsaturated compounds and (f) 0-5% by weight of molecular weight regulators, and, if appropriate, the free acid groups of the copolymers subsequently having been partly or completely neutralized by addition of bases and converted into water-soluble or colloidally water-dispersible copolymer salts. In addition, processes for the preparation of the copolymers by solution or emulsion copolymerization and, if appropriate, subsequent conversion thereof into the copolymer salts, and the use of the products as viscosity-increasing and rheology-modifying substances in aqueous systems, in particular aqueous dispersions, preferably for thickening emulsion paints, emulsion gloss lacquers, textile printing pastes and paper printing pastes, and furthermore as sizing agents in the textile industry.

Production of methacrylic acid

Abstract: PURPOSE: To obtain methacrylic acid in high yield along with stable use of the catalysts for a long period of time, by introducing compound(s) selected from methacrolein, isobutyraldehyde and isobutyric acid into a specific catalytic bed packed with plural catalyst differing in activity from one another followed by oxidation with O 2 . CONSTITUTION: At least one compound selected from methacrolein, isobutyraldehyde and isobutyric acid is introduced into a catalytic bed prepared by packing (A) plural reaction zones provided by dividing a reaction tube in its axial direction with (B) plural catalysts differing in activity from one another in such a way as to rise in catalytic activity from the stock gas inlet toward the outlet, followed by oxidation with O 2 or an O 2 -contg. gas, thus obtaining the objective methacrylic acid. With this method, high yield can be attained and the heat storage at the hot spots within the catalytic bed suppressed. Thereby, the catalysts will be prevented from deterioration and used stably for a long period of time. COPYRIGHT: (C)1992,JPO&Japio

Stabilization of soluble manganese and its reaction products

Abstract: The instant invention is directed to a process for inhibiting the precipitation of dissolved manganese ion and its reaction products in aqueous solutions, comprising adding to the aqueous solution 0.1 to 20 ppm of a copolymer of an unsaturated carboxylic acid or salt selected from the group consisting of acrylic acid and methacrylic acid and an unsaturated sulphonic acid or salt selected from the group consisting of 2-acrylamido-2-methylpropylsulphonic acid and 2-methacrylamido-2-methylpropylsulphonic acid.

Contact adhesive dispersions for the production of self-adhesive articles, for example those having a polyolefinic base

Abstract: Contact adhesive dispersions contain (A) an aqueous dispersion of a copolymer A which has a glass transition temperature below 0° C. and consists of (a) from 50 to 99% by weight of esters of acrylic acid with non-tertiary alkanols, (b) from 0 to 50% by weight of esters of acrylic or methacrylic acid and/or vinyl esters and/or (meth)acrylonitrile and/or styrene and/or tert.-butyl acrylate, (c) from 0.5 to 5% by weight of monoolefinically unsaturated carboxylic acids and/or their amides which are unsubstituted or substituted at the nitrogen atoms by alkyl and/or alkylol radicals, and/or hydroxyalkyl (meth)acrylates, and (d) from 0.5 to 5% by weight of carbonyl-containing monomers and (B) from 0.05 to 2 moles of a water-soluble dihydrazine compound per mole of carbonyl groups present in the copolymer A.

Wound treating agent

Abstract: The present invention provides a wound treating agent in powder form based on a swellable organic polymer, which comprises a cross-linked polymer of a hydrophilic acrylic or methacrylic acid derivative, which polymer is permeated by a gellable polysaccharide and/or protein or polypeptide, the agent being obtainable by polymerizing a hydrophilic acrylic or methacrylic acid derivative in the presence of a dissolved, gellable polysaccharide and/or protein or polypeptide and of a cross-linking agent. The present invention also provides a process for the production of this wound treating agent, wherein a hydrophilic acrylic or methacrylic acid derivative is polymerized in an aqueous solution of a gellable polysaccharide and/or protein or polypeptide in the presence of a cross-linking agent and of a conventional polymerization initiator, to give a transparent gel which is dried and pulverized.

Basic dye ink formulations and methods

Abstract: A printing ink particularly suitable for use in flexographic and letterpresses includes a basic dye, a polyhydric alcohol, water soluble carboxylic acid containing polymer and optionally water, thickeners, corrosion inhibitors and biocides. Preferably the water soluble carboxylic acid containing polymer is a homopolymer or copolymer of acrylic or methacrylic acid. The ink has an extremely high affinity for cellulosic and hemi-cellulosic substrates such as Kraft paper and newspaper. It forms a permanent bond to such substrates but does not easily dry out on the press rollers.

Thermal behavior of random copolymers of methacrylic acid and tert-butyl methacrylate

Abstract: Etude entre 25 et 300°C. A 200°C il se forme des liaisons anhydride plus intramoleculaires qu'intermoleculaires

Cosmetic compositions for hair and skin which contain a methacrylic or acrylic acid copolymer, an alkyl acrylate and/or methacrylate and an allyl derivative

Abstract: A cosmetic composition contained in a suitable carrier comprising at least one copolymer of acrylic or methacrylic acid, an alkyl acrylate and/or methacrylate and an allyl derivative having repetitive units which correspond to the following formulae: ##STR1## wherein: R 1 and R 2 constitute a hydrogen atom or a methyl radical, R 3 constitutes a linear or branched-chain alkyl radical having from 1 to 20 carbon atoms, R 4 constitutes --OH, --NHCONH 2 , or --OCOR 5 , R 5 constitutes a linear or branched-chain alkyl radical having from 1 to 5 carbon atoms, x constitutes 40 to 90 weight percent, y constitutes 8 to 50 weight percent, z constitutes 2 to 25 weight percent, and the sum of x+y+z is from 80 to 100 weight percent. The cosmetic composition is especially useful as a composition for the hair and skin.

Synthesis of 2,2-dimethyl-4-methyleneglutaric acid and derivatives

Abstract: The process comprises dimerizing methacrylic acid derivatives in the presence of an organic Co(II) glyoxime to produce 2,2-dimethyl-4-methyleneglutaric acid and/or derivatives thereof. Methacrylic acid derivatives include methacrylic acid or derivatives of methacrylic acid. The composition produced by the process comprises a glutaric dimer acid which can be further polymerized to form high molecular weight polymer useful as a binder in protective coatings.

Method of making and using novel scale inhibiting terpolymer

Abstract: METHOD OF MAKING AND USING NOVEL SCALE INHIBITING TERPOLYMER ABSTRACT OF THE DISCLOSUREA two-step process is disclosed for preparing an essentially non-crosslinked random copolymer of acrylic acid or methacrylic acid with esters of the acids which esters are formed by reaction with an alkylene oxide. Raw materials, are (meth)acrylic acid and alkylene oxide. In a first step, a predetermined amount of a particular esterification catalyst is used, and with close control of process conditions, the (meth)acrylic acid yields both mono- and polyalkoxylated esters. In the second step polymerization is effected without separating the esterification catalyst or purifying the esters formed. The resulting random copolymer formed consists essentially of a terpolymer of (i) acrylic acid or methacrylic acid (together "(meth)acrylic"), (ii) a hydroxymonoalk-ylated (meth)acrylate, and (iii) a hydroxypolyalkyleneoxylated (meth)acrylate the monomeric moieties being present in specified relative proportions. Despite the presence of the polyalkyleneoxylated ester moiety the terpolymer is soluble in water, and is surprisingly effective in the treatment of industrial process water used in recirculating water systems.

Process for producing microcapsules and microcapsule slurry

Abstract: When obtaining microcapsules by covering a hydrophobic material with an aminoaldehyde polycondensation product as a wall-forming material in an acidic aqueous medium containing an anionic water-soluble polymer, a microcapsule slurry having a high solid content and low viscosity can be obtained by using as the anionic water-soluble polymer a multi-component copolymer consisting as essential monomer components thereof of at least three types of acrylic monomers selected respectively from (A) acrylic acid and/or methacrylic acid, (B) acrylonitrile and/or methacrylonitrile and (C) an acrylamidoalkylsulfonic acid and/or sulfoalkyl acrylate. Over a wide pH range, the microcapsule slurry obtained in accordance with this invention undergoes little viscosity changes and exhibits neither destruction of its dispersed state nor coagulating tendency. Resulting microcapsules have a sharp particle size distribution and are equipped with dense wall films.

Agent for forming surface-protecting layer on coated paper

Abstract: An agent for forming a surface-protecting layer on a coated paper, which comprises an aqueous solution of an alkali metal salt, ammonium salt or amine salt of a graft copolymer and an epoxy group-containing cross-linking agent incorporated in the aqueous solution, said graft copolymer comprising (A) 10 to 60% by weight of a polyvinyl alcohol polymer selected from the group consisting of partially saponified polyvinyl alcohols, polyvinyl alcohols containing copolymerized units of a vinyl monomer having carboxyl group, and polyvinyl alcohol having the recurring vinyl alcohol units esterified with a higher fatty acid, (B) 20 to 70% by weight of acrylamide or methacrylamide, (C) 5 to 30% by weight of at least one member selected from the group consisting of acrylonitrile, methacrylonitrile, lower alkyl esters of acrylic acid and methacrylic acid and hydroxyl lower alkyl esters of acrylic acid and methacrylic acid, and (D) 5 to 20% by weight of at least one vinyl monomer containing a carboxyl group.

Process for the preparation of esters of (meth)-acrylic acid, and their use

Abstract: 1. A process for preparing an ester of acrylic or methacrylic acid with a hydroxyl-containing organic compound, which comprises esterifying a saturated polyester which contains no fewer than 2 free hydroxyl groups per molecule and may contain ether groups or a saturated polyether which contains no fewer than 2 free hydroxyl groups per molecule, this polyester or polyether having an average molecular weight ~Mn of from 400 to 4,000, with from 100 to 150 mol %, based on the OH groups of the polyester or polyether, of acrylic acid or methacrylic acid in the presence of an acidic esterification catalyst and one or more hydrocarbons forming an azeotropic mixture with water and a small amount of a polymerization inhibitor at elevated temperature with azeotropic removal of the resulting water, after the esterification removing the hydrocarbon by distillation and after neutralization of the esterification catalyst reacting the remaining acrylic or methacrylic acid with an amount, equivalent to the acid number, of an epoxy compound having no fewer than two epoxy groups per molecule until an acid number =< 5 mg of KOH/g is obtained.

Blends of aromatic polycarbonate resin, olefin polymers or copolymers and acrylate or methacrylate-copolymer resins

Abstract: Thermoplastic molding compositions are described which comprise an admixture of (a) an aromatic polycarbonate resin, (b) an olefinic polymer or copolymer and (c) a third component which is a copolymer of an olefin and an acrylate, methacrylate, acrylic acid or methacrylic acid. The presence of the third component enhances impact strength in thicker sections and improves weld line strength.

Process for purification of 1,2-unsaturated carboxylic acids and/or esters thereof

Abstract: A 1,2-unsaturated carboxylic acid or its ester such as acrylic or methacrylic acid or its alkyl ester is purified to remove aldehyde impurities contained therein by treating the acid or its ester with a mercapto containing compound in the presence of an acid catalyst.

Internally crosslinkable acrylic polymers and diglycidyl esters of dibasic acids

Abstract: Acrylic polymers prepared from hydroxy alkyl esters of acrylic or methacrylic acid, glycidic monomer and ethylenically unsaturated monomer, as well as enamels based on mixtures of such polymers and diglycidyl esters of dibasic acids.