摘要:
Ammeline-melamine-formaldehyde resins (AMFR) containing from 5-100% ammeline were synthesized by the polymerization of the sodium salt of ammeline, which must be made in advance, melamine, and formaldehyde in basic medium (pH = 9.2-10.0). In this copolymerization, it is possible to make uniform random AMFR resins with any mole ratio of ammeline salt to melamine. Preferably the AMFR resin will contain from 5-10% ammeline. As an "ionomer" or a "poly-electrolyte," both the solid and solution properties of these resins (such as melting temperature, solubility, solution stability, etc.) depended directly on the mole ratio of ammeline to melamine and formaldehyde, and/or on the pH value of the medium in which the AMFR resin was present. The pH value controlled the ammeline rings/ammeline's salt groups and also the ratio of unprotonated to protonated amino groups on both the melamine and ammeline rings. These polymers have different solubilities, cloud points and solution lifetimes (which depend on pH) than melamine-formaldehyde resins. AMFR systems containing from 5-10% ammeline are more flexible than MFR resins and exhibit different adhesion properties than MFR resins.
摘要:
A method for the manufacture of an methylolated cyclohexanecarboguanamine by subjecting cyclohexanecarboguanamine to the methylolating reaction with a formaldehyde while keeping the amount of an alcohol present during the process of methylolating reaction below 20% by weight based on the amount of said formaldehyde and keeping the pH value of the reaction system in the range of 8 to 13 and the temperature thereof in the range of 50° to 80°C between the time said reaction is started and the time said reaction is completed.
摘要:
Modifiziertes Melaminharz, bestehend aus einem praktisch unveretherten Melamin/Formaldehyd-Vorkondensat, Wasser und gegebenenfalls einem wassermischbaren niederen Alkanol und gegebenenfalls in wäßrigen Melaminharzen üblichen Modifizierungsmitteln, mit einem Molverhältnis von Melamin:Formaldehyd von 1:1,05 bis 1:1,27 und einer Wasserverdünnbarkeit von 1:3 bis 1:0,05 als Modifizie rungsmittel 0,3 bis 6,5 Gew.% Hydroxyethylaminotriazine der Formel 1 worin R¹ Alkyl, Aryl oder eine Gruppe der Formel R², R⁴ und R⁶ unabhängig voneinander Wasserstoff, β-Hydroxyethyl oder Alkyl, R³ und R⁷ unabhängig voneinander Wasserstoff oder β-Hydroxyethyl, R⁵ β-Hydroxyethyl bedeuten oder R² und R³ und/oder R⁴ und R⁵ und/oder R⁶ und R⁷ gemeinsam die zweiwertige Gruppe der Formel
摘要:
Die Erfindung betrifft ein Verfahren zur Herstellung von veretherten oder nichtveretherten Aminoplastharzen. Aminotriazine der allgemeinen Formel (I) worin X für Wasserstoff, einen Alkylrest, einen Phenylrest, einen Alkylphenylrest oder für den Rest -NH 2 steht, werden mit einem β-Hydroxialdehyd der allgemeinen Formel (II) worin R', R" und R"' untereinander gleich oder verschieden sind und für Wasserstoff oder eine Alkylgruppe stehen oder R" bzw. R"' zusammen mit dem a-Kohlenstoffatom einen Cyclopentan- oder Cyclohexanring bilden sowie R" und/oder R"' außerdem für einen Hydroxialkylrest und R" für einen Phenylrest stehen können, umgesetzt, wobei im Falle der Herstellung der veretherten Aminoplastharze die Umsetzung in Gegenwart mindestens eines Alkohols und eines sauren Katalysators, im Falle der Herstellung der nichtveretherten Aminoplastharze die Umsetzung in Gegenwart oder Abwesenheit eines sauren Katalysators durchgeführt wird. Die erfindungsgemäß hergestellten Aminoplastharze eignen sich als Lackrohstoffe.
摘要:
Hemiacetals are prepared by reacting monohydric primary and secondary alcohols with adducts of acrolein and isocyanuric acid. The hemiacetals are useful for producing polymer compositions as polymerizing or crosslinking agents for polyfunctional compounds containing hemiacetal-reactive groups such as amines, amides, alcohols, thiols and oxiranes. The polymer compositions are useful in molding, laminating, coating and adhesive applications.
摘要:
Compositions for producing aminoplast products by means of melt processing consist of: A) 95 to 99.9 % by mass of solvent-free meltable polycondensates of melamine resins having molar masses ranging from 300 to 300000; A) 0.1 to 5 % by mass of weak acids serving as thermoinducible curing agents consisting of: acidifiers of the blocked sulfonic acid type; aliphatic C4-C18 carboxylic acids; aromatic C7-C18 carboxylic acids; alkali salts or ammonium salts of phosphoric acid; C1-C12 alkyl esters or C2-C8 hydroxyalkyl esters of C7-C14 aromatic carboxylic acids or of inorganic acids; salts of melamine or of guanamines having C1-C18 aliphatic carboxylic acids; anhydrides, half-esters or half-amides of C4-C20 dicarboxylic acids; half-esters or half-amines of copolymers consisting of ethylenically unsaturated C4-C20 dicarboxylic acid anhydrides and ethylenically unsaturated monomers of the C2-C20 olefin type and/or C8-C20 vinyl aromatic compounds; and/or salts of C1-C12 alkyl amines or alkanolamines having C1-C18 aliphatic, C7-C14 aromatic or alkylaromatic carboxylic acids and inorganic acids of the hydrochloric acid, sulfuric acid or phosphoric acid type, and; B) optionally up to 400 % by mass of fillers and or reinforcing fibers, up to 30 % by mass of additional reactive polymers of the ethylene copolymer, maleic anhydride copolymer, modified maleic anhydride copolymer, poly-(meth)acrylate, polyamide, polyester and/or polyurethane type, and up to 4 % by mass, each time with regard to the polycondensates of melamine resins, of stabilizers, UV absorbers and/or auxiliary agents. These inventive compositions can be processed by means of melt processing into products such as panels, coated supporting materials, profiled pieces, pipes, injection-molded articles, fibrous products and laminates.
摘要:
The invention relates to synthetic material dispersions consisting of (a) an aqueous phase of solutions of hydrophilic melamine resin precondensates and a latent hardening catalyst in water or in mixtures of water and alcohols C1-C6, (b) an organic nanophase in the form of nanometric droplets and/or nanoparticles derived from 70-99 % of the melamine resin precondensates which are insoluble in water and etherifieds and contain hardening acid catalysts and acid impermiability agents, (c) dispersion agents at a concentration of 1-10 mass % in relation to the total mass of the melamine resin precondensates. The ratio between the hydrophilic melamine resin precondensates and the water and etherifieds-insoluble melamine resin precondensates ranges from 10:1 to 1:10, the water content in the inventive synthetic material dispersions ranging from 8 and 50 mass %. Said synthetic material dispersions are used for producing flat coated products which are externally used in the form of laminates, of coated flat carrying materials or moulded coated bodies for construction or for sports and recreation.