Resorcinol component

HMMM is commonly used in HRH systems for good adhesion. It is probably the most commonly used methylene donor, which reacts with the resorcinol component of the HRH to achieve the desired adhesion. 

Reinforcing Resins. Reinforcement and stiffness of a compound can also be achieved with the use of reactive resins. Resins consisting of two-component systems of resorcinol or resorcinol condensation products and a methylene donor such as hexamethoxymethylmel amine (HMMM) or hexamethyltetramine (HMT) are the most popular in tires. These materials can be prereacted and added to the formula, or for more effective results they can react in situ ie, they can be added separately into the formula and react when the tire is vulcanized. 

Benzenedisulfonic acid [831-59-4] (disodium salt), produced by the neutralization of the disulfonic acid with sodium sulfite [7757-83-7] is used in the manufacture of resorcinol [108-46-3] (1,3-benzenediol) (2), a chemical component found in mbber products and wood adhesives (72). The disodium salt is fused with sodium hydroxide, dissolved in water, and acidified to produce resorcinol, which is isolated via extraction (73). 

In the case of low temperature tar, the aqueous Hquor that accompanies the cmde tar contains between 1 and 1.5% by weight of soluble tar acids, eg, phenol, cresols, and dihydroxybenzenes. Both for the sake of economics and effluent purification, it is necessary to recover these, usually by the Lurgi Phenosolvan process based on the selective extraction of the tar acids with butyl or isobutyl acetate. The recovered phenols are separated by fractional distillation into monohydroxybenzenes, mainly phenol and cresols, and dihydroxybenzenes, mainly (9-dihydroxybenzene (catechol), methyl (9-dihydtoxybenzene, (methyl catechol), and y -dihydroxybenzene (resorcinol). The monohydric phenol fraction is added to the cmde tar acids extracted from the tar for further refining, whereas the dihydric phenol fraction is incorporated in wood-preservation creosote or sold to adhesive manufacturers. Naphthalene Oils. Naphthalene is the principal component of coke-oven tats and the only component that can be concentrated to a reasonably high content on primary distillation. Naphthalene oils from coke-oven tars distilled in a modem pipe stiU generally contain 60—65% of naphthalene. They are further upgraded by a number of methods. 

Resorcine Brown R [5850-16-8] (27) (Cl Acid Brown 14, Cl 20195) is a symmetrical primary disazo dye with bihmctional coupling component (resorcinol). 

Of these dyes, Acid Yellow 151 (37) still has the greatest market among the yellows. As reported by USITC, production had increased to 1989 tons in 1985 from 706 tons in 1975. It is produced by coupling diazotized 2-amino-l-phenol-4-sulfonamide to acetoacetanilide followed by metallizing with cobalt to obtain a 1 2 cobalt complex. Acid Orange 24 (38), which is sulfanilic acid coupled to resorcinol to which diazotized mixed xyUdines have been coupled, is an unsymmetrical primary diasazo dye with a bihinctional coupling component. 

Dye formation is complex because shading is achieved by employing several developers and several couplers in the same dye bath. The process is illustrated by -phenylenediamine, which is oxidized by the peroxide to a quinone diimine. This short-Hved intermediate can react, for example, with resorcinol to yield a brownish indoaniline. Table 17 provides some insight into the many interactions that exist from just a few components. Further shading is possible by including semipermanent colorants (see Table 16), especially nitroaniline derivatives. 

Developments in glued laminated structures and panel products such as plywood and chipboard raises the question of the durability of adhesives as well as wood. Urea-formaldehyde adhesives are most commonly used for indoor components. For exterior use, resorcinol adhesives are used for assembly work, whilst phenolic, tannin and melamine/urea adhesives are used for manufactured wood products. Urea and casein adhesives can give good outdoor service if protected with well-maintained surface finishes. Assembly failures of adhesives caused by exudates from some timber species can be avoided by freshly sanding the surfaces before glue application. 

Quantitative studies based on kinetic measurements using strongly electrophilic diazonium ions and, as coupling components, 1-naphthol, 2-naphthol-6-sulfonic acid, and resorcinol in aqueous acid were made by Sterba and coworkers (Kropacova et al., 1970 Kavalek et al., 1970 Sterba and Valter, 1972 Machackova et al., 1972a). In a typical case (2,6-dichloro-4-nitrobenzenediazonium ion and 1-naphthol) the dependence of the logarithm of the measured rate constant (ks) on pH was linear with a slope of 1. At pH < 1, however, a practically constant value of ks was obtained. The measured rate constants therefore correspond to Scheme 12-62, in which the first term relates to the reaction of the naphthoxide ion and the second to that of the undissociated naphthol Ka is the acidity constant of 1-naphthol. 

Jessner s Solution has been used for over 100 years as a therapeutic agent to treat hyperkera-totic epidermal lesions [1]. This superficial peeling agent constitutes a mixture of salicylic acid, resorcinol, and lactic acid in 95% ethanol. Jessner s solution causes loss of corneocyte cohesion and induces intercellular and intracellular edema. Jessner s typically induces wounding to the level of the papillary dermis. Historically, resorcinol (a key component of Jessner s peels) was used in concentrations of 10-50% in the early twentieth century. High concentrations of resorcinol were associated with side effects such as allergic contact dermatitis, irritant contact... 

Fig. 3.ia-c. Chemical structures of Jessner s Peel components (a Salicylic acid, b Resorcinol, and c Lactic acid)... 

Koga et al. complexed oxo acids like methyl phenylphosphonate with bis(resorcinol) quinoline derivative 57 [83], Anslyn and coworkers presented a more rigid polyazacleft containing hydrogen bond acceptor and donor sites in form of pyridine rings and amino groups, respectively. The formation of the 3 1 complex 58 with dibenzyl phosphate is assumed, in which the four components are spatially fixed by a net of H-bonds [84]. 

Fig. 8. Dependence of limiting conversion on the ratio of the components (1) model calculations (2) diglycidyl ether of resorcinol with m-phenylenediamine 79 ...

Resorcinols. Condensation of this diene with the ketal of a fi- keto acid derivative results in a resorcinol with complete regiocontrol. Thus, the TiCl4-catalyzed reaction of 1 with ketal ester 2 results in the resorcinol 3 in 72% yield. However, use of the acid chloride 4 corresponding to 2 in the same reaction results in the isomeric resorcinol, methyl olivetolate (5). The regiocontrol is based on the reactiv ity order acid chloride > ketal > ester. The resorcinol 5 was used in a biomimetic synthesis of the chromene A1 -tetrahydrocannabinol (6), a component of marijuana. 

Phenols, Naphthols (e.g., 39-47). Phenols mainly couple at the 4-position, or at the 2-position if the 4-position is occupied, p-Hydroxybenzoic acid couples with elimination of C02 resorcinol couples twice initially at the 4-position, and with a second equivalent of diazonium compound at the 2-position under acid conditions or at the 6-position under alkaline conditions. a-Naphthols mainly couple at the 4-position, in addition to which varying quantities of 2- and 2,4-coupling products are obtained, depending on the diazo component. p-Naphthol couples at the 1-position. Substituents in the 1-position, such as S03H, COOH, Cl, CH2OH, or... 

First, 1 2 metal complexes of (mainly mono-) azo dyes, without sulfonic or carboxylic acid groups, and trivalent metals (see Section 3.11). The metals are preferably chromium and cobalt nickel, manganese, iron, or aluminum are of lesser importance. Diazo components are mainly chloro- and nitroaminophenols or amino-phenol sulfonamides coupling components are (3-naphthol, resorcinol, and 1-phe-nyl-3-methyl-5-pyrazolone. Formation of a complex from an azo dye and a metal salt generally takes place in the presence of organic solvents, such as alcohols, pyridine, or formamide. An example is C.I. Solvent Red 8, 12715 [33270-70-1] (1). 

Thus, it was anticipated that co-crystallization of resorcinol with 4,4 -bpe would yield a four-component molecular assembly, 2(resorcinol)-2(4,4/-bpe), held together by four O-H N hydrogen bonds (Figure 8). The C=C bonds of the assembly would be arranged in a parallel fashion and separated by approximately 4.0 A. UV-irradiation of the crystalline solid would produce, stereospecif-ically, rch-tetrakis(4-pyridyl)cyclobutane (4,4 -tpcb). 

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