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Although they were synthesised for the first time over 100 years ago, the present-day products of that type are still considered an important sector in the polymer chemistry. Although it is possible to dissolve more than 10% melamine in aqueous formaldehyde it is in general not desirable to do so because of the possible formation of a gel as described in our copending application referred to above. a phenol molecule. When preparing many types bf phenol-formaldehyde condensation products the resin must be dehydrated when the desired stage of condensation has been reached. By the condensation reaction, high molecules are formed, which deteriorate the quality of phenolic resin. To this mixture of phenol and cardanol, 0.6 and 0.8 mol of formaldehyde were added separately, under acidic conditions, at five different temperatures ranging between 80 and 120°C with an interval of 10°C. One component is first coated on one of the members to be bonded. Novolac resins are amorphous thermoplastic polymers produced by reacting formaldehyde with phenol under acidic conditions. condensation of phenol and formaldehyde in presence of calcium hydroxide as catalyst has been patented by Jellinek and co-workers [16]. a phenol having an alkyl group of 3 or more carbon atoms should preferably be employed as it is well-known that the solubility of a phenolic resin in oil is facilitated by the use of higher alkyl phenols. When the ammonia is used, it helps to separate reaction mixture containing In our copending application Serial No. Example 3 200 parts of phenol, 239 parts of a 50% solution of formaldehyde containing 7% melamine as stabilizer and 5 parts of a 25% solution of NaOH were heated at 100° C. for 14 minutes. There were By the addition of melamine, however, it is possible to provide stable solutions of formaldehyde containing as much 40-50% formaldehyde. A principal object of the invention is the preparation of phenolic condensation products having better light-stability, color, hardness and... 528/158.5, 528/163, Click for automatic bibliography The first step is the rate-determining step. After 28 minutes and at a temperature of 180* C. the dehydration was completed. ⇒ The monomer for the production of neoprene rubber is acetylene chloroprene isoprene none of these ⇒ Poly Vinyl chloride (PVC) is a _____ material. The following specific examples are given to Illustrate a few of the possible variations permissible in the preparation of improved phenolic condensation products employing melamine-stabilized formaldehyde in accordance with our invention. This is the first stage of the reaction and a brittle thermoplastic resin is produced which can be melted but cannot crosslink to form a solid network. The melamine-stabilized formaldehyde which we employ in practicing our invention is prepared simply by dissolving 1-10% of melamine or methylol melamines in an aqueous formaldehyde solution preferably by adding the melamine and heating to 60-80° C. for a short time. To inhibit the condensation reaction, much more phenol concentrations against woody materials are needed to be added to the liquefaction system. Eldew SL-205 The invention is a method of gluing wood using a reactive two-component thermosetting adhesive such as a phenol-resorcinol-formaldehyde (PRF) condensation product. Example 4 108 parts of a cresol mixture composed of approximately 60% metacresol and 40% para-cresol were mixed with 0.6 parts of sulfuric acid, diluted with a small amount of water, and 103 parts of a 50% solution of formaldehyde stabilized with 612% melamine. Since phenol-formaldehyde resins are notoriously poor in this respect an improvement in their light stability is of great importance. Phenol-formaldehyde resins are heat-resistant and waterproof, though somewhat brittle. We have now discovered that a number of unexpected and surprising advantages are obtained by using formaldehyde stabilized with these amounts of melamine in the preparation of phenol-formaldehyde condensation products. Any of the common phenols or alkyl substituted phenols such as phenol itself, cresol, commercial cresylic acids, xylenols and the like may be used. In the preparation of phenol-formaldehyde condensation products in which concentrated solutions of melamine-stabilized formaldehyde, for example 40-50%, are used, the condensation reaction proceeds much more rapidly and a considerable saving in time is effected. Typical alkyl phenols which may be used are n-butyl phenol, p-tertiary butyl phenol, p-tertiary amyl phenol, etc. Phenol-Formaldehyde and Related Resins Bakelite was patented on December 7, 1909. The following sequence of reaction may be considered for this polymerization. The old and fresh formaldehyde produced a vesicular eczematization and the benzaldehyde only erythema. Phenol formaldehyde resins (PF) or phenolic resins are synthetic polymers obtained by the reaction of phenol or substituted phenol with formaldehyde. When using melamine-stabilized formaldehyde of 40-50% strength it will be found that the reaction proceeds much more rapidly and care must be taken that condensation does not proceed beyond the s desired stage. They are produced by reacting phenol (C 6 H 5 OH) with formaldehyde (HCOH). When preparing many types bf phenol-formaldehyde condensation products the resin must be dehydrated when the desired stage of condensation has been reached. A flavor resembling oil of cloves, produced by the action of some wild yeast strains on some wort compounds The flavor in German "weisse" beers, [but] not a necessary component of wheat beers A resin or plastic, usually thermosetting, made by condensation of a phenol with an aldehyde and used for molding, insulating, coatings and adhesives Encyclopædia Britannica, Inc. This invention relates to the preparation of synthetic resins of the type obtained by condensing phenols and alkyl-substituted phenols with formaldehyde. The phenol-formaldehyde condensation is carried out in much the same manner as when using ordinary formaldehyde, due regard being given however to the concentration of the form60 aldehyde solution employed. The resins produced according to our invention may be cast or made into molding compositions or varnishes according to procedures well understood in the art. 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