摘要:
Preparation of binder resins having improved flow properties in the manufacture of curable fiber composites of natural or synthetic fiber materials, which are based on thermosetting novolaks which contain crosslinking agents and contain practically no free mononuclear phenols, by admixing polyglycols and/or polycarboxylic acids or anhydrides thereof and/or acid esters of polyglycols and polycarboxylic acids, preferably in amounts of in total up to 20% by weight, to the novolaks in the melt, pulverizing the mixture, after cooling to room temperature, and mixing it intimately with the required amount of pulverulent crosslinking agent.
摘要:
Preparation of vulcanizable rubber mixtures and vulcanized compounds thereof having improved adhesion to reinforcing supports based on steel cord and textile fibers, in which effective amounts of modified novolaks are added to the rubber mixtures as adhesion promotors, which are prepared by simultaneous reaction of polyhydric phenols with aldehydes and unsaturated hydrocarbons with acid catalysis at elevated temperature and do not contain any troublesome proportions of free starting phenols. Rubber mixtures according to the invention can be processed in an easy advantageous manner without liberating toxic substances which might be detrimental to persons working in processing and/or to the environment. Rubber mixtures according to the invention which can be prepared, processed and vulcanized by known methods by thorough mixing of the components are highly suitable for the manufacture of industrial rubber articles containing reinforcing supports based on steel cord and textile fibers such as, for example, tubings, fan belts, conveyor belts and tires, the resulting vulcanized compounds having excellent adhesion properties to the reinforcing supports mentioned in combination with a surprisingly good constancy of properties upon exposure to moisture.
摘要:
Modified novolaks based on phenols which are trifunctional with respect to formaldehyde and contain, as modifying components, terpenes and unsaturated carboxylic acids or derivatives of these compounds, the weight ratio between the terpenes and the unsaturated carboxylic acids or derivatives thereof being in the range from 98.5:2.5 to 2.5:98.5 and the weight ratio between the phenolic component and the sum of the modified components being in the range from 95:5 to 5:95 and the modified novolaks having a melting point greater than 45.degree. C.Process for the preparation of the modified novolaks by admixing the modifying components indicated with non-modified novolaks in the necessary amounts at temperatures between 80.degree. and 300.degree. C.Use of the modified novolaks as reinforcing resins for rubber and elastomers, as tackifying agents for rubber, as binders for friction linings, curable molding compositions, impregnants, coatings, paints and binders for finely divided inorganic substrates.
摘要:
Polymers which contain units of 4-hydroxystyrene and/or of 4-acetoxystyrene, where appropriate in a mixture with other comonomer units, in particular butadiene, can be used in place of phenolic or resorcinol resins as reinforcing resins and adhesion promoters in rubber mixtures. These polymers are distinguished by the fact that, coupled with at least equally good effectiveness, they do not release any phenolic materials into the environment on incorporation into rubber mixtures.
摘要:
A synthetic resin binder comprising an aqueous mixture of phenolic resins and optionally other additives wherein the mixture of phenolic resins comprises (I) at least one phenol-resol and (II) at least one co-condensate of at least one monohydric phenol and at least one polyhydric phenol with formaldehyde and wherein in component (II) the molar ratio of the quantities of formaldehyde used to the sum of phenols is within the range of from 0.6:1 to 1.5:1, a method for the manufacture of an abrasive by means of said synthetic resin binder and the abrasives itself.
摘要:
Process for the manufacture of an abrasive material comprising at least two binder layers formed from at least one aqueous resol I prepared from a monohydric phenol and formaldehyde (molar ratio of phenol to formaldehyde 1:(1.1 to 2.5)) by the application of a first binder layer onto a carrier material, scattering abrasive particles thereon, drying the covering layer in a horizontal dryer to displacement resistance and thereafter cooling with an air stream, application of a second binding agent layer and in similar manner to the first step, drying to imprint resistance and thereafter cooling, whereby the heating and cooling are each effected by means of an air stream through slit nozzles arranged transversely to the direction of travel of the abrasive web and, after loosely forming the product into a roll, final curing is effected on the product in roll form, the coated carrier material being conveyed at speeds above 5 m/min through the dryers which have well defined and individually controllable heating and cooling zones and the air stream has a velocity of 5 to 200 m/s at the nozzle outlets and a temperature of 20 to 300.degree. C., the air being extracted through adjacent extraction nozzles.
摘要:
Contact adhesives based on polyurethane rubber, in which the rubber solution is combined with 2.5 to 100% by weight, based on the solid rubber, of a phenolate of titanium, zirconium and/or preferably aluminum and optionally hydroxyl group-containing compounds, and their use for bonding organic or inorganic material such as leather, polyvinyl chloride, rubber, textiles, polyurethane or glass.
摘要:
Rubber vulcanizates having a reduced heat evolution when subjected to dynamic deformation, prepared from vulcanizable rubber mixtures containing at least one type of rubber, a reinforcing resin system based on curable phenolic resins and other customary constituents, the vulcanizable rubber mixtures having been prepared from at least two rubber mixtures of different compositions. A process for their preparation by preparing in each case at least two different rubber mixtures differing from one another in their content of rubber, filler, oil, reinforcing resin system and, if appropriate, thermoplastic copolymer, by mixing the constituents thereof, then mixing the resulting mixtures with one another and vulcanizing the resulting final mixture.The use of the vulcanizable rubber final mixtures for the production of mechanical rubber goods and tires.
摘要:
Heat-stable moldings for brake linings, clutch linings and grinding tools are produced by molding and vulcanizing a mixture containing a natural or synthetic rubber in the presence of a sulfur-free vulcanizer/activator system comprising phenol resols which contain at least 90 mol % of p-(C.sub.3 -C.sub.12)-alkylphenols, based on the total amount of phenols, and a substance, or mixture of substances, which acts as a Bronsted or Lewis acid under the reaction conditions of the rubber-vulcanization, at a temperature of 120.degree. to 250.degree. C.
摘要:
An adhesive composition based onI. 100 parts by weight of a block copolymer with at least two polymer blocks (A) and at least one polymer block (B), wherein the polymer blocks (A) comprise non-elastomeric blocks with an average molecular weight of from 2000 to 125,000 derived from an aromatic hydrocarbon substituted by one of the groups consisting of the members monoalkenyl and monoalkylidene and wherein not more than 25% of the original double bonds are hydrogenated, and polymer block (B) is an elastomeric block with an average molecular weight of from 10,000 to 250,000 derived from a conjugated diene, wherein at least 75% of the aliphatic unsaturated bonds are hydrogenated;Ii. 10 to 200 parts by weight of at least one cohesion-increasing resin selected from the group consisting of an alkylphenol resin, an arylphenol resin, a phenol-colophony-adduct and a rosin-modified phenol resin;The components dissolved in at least one solvent and a process of bonding one substrate to another substrate which comprises applying to the surface of either substrate an adhesive composition as claimed in claim 1 and placing the surfaces to be bonded together.