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Phenols alkylated phenol

Phenol alkylation Phenol Gaseous alkenes None... [Pg.382]

Intramolecular phenol alkylation. Phenols of type 1,3, and 4 when treated with ethylmagnesium bromide in benzene at reflux undergo intramolecular alkylation. These reactions are thought to proceed via o-quinone methide intermediates such as b formulated for the case of 1. These cyclizations fail with NaH or n -butyllithium as... [Pg.114]

Figure 10 shows the orthogonal even mass maps of the C H2 -eO C H2 -i8 components that correspond to phenol-alkyl phenols and the anthracene-phenanthrenes and alkyl derivatives, respectively. There is a clear increase in relative concentration of these polyaromatics with the... [Pg.27]

Phenolic novolak resins and high styrene SBR resins are used for reinforcing and increasing the hardness and modulus of rubber compounds. Resorcinol novolak resins are used as a part of the adhesion system between rubber and brass plated steel cord or organic fibers. Both phenolic novolak and resorcinol novolak resins require the addition of a methylene donor such as hexamethoxymethylmelamine (HMMM) or hexamethylenetetramine (HMTA) to fully crosslink and become a thermoset. Phenol, alkyl phenols, and resorcinol can be reacted in bulk or in a polymeric formulation with methylene donors. Typical donors are 2-nitro-2methylpropanol (NMP), HMTA, and HMMM, used to produce a thermoset resin network in the... [Pg.194]

Methoxyphenols (e.g., guaiacol), 2,6-Dimethoxyphe-nols (eg., syringol), Catechols, Phenol, Alkyl phenols. Methanol, Other oxygenated aromatics (e.g., coumaran), furfural, acetic acid, other Cj-C4 oxygenates (e.g., formaldehyde, formic acid, acetone, acetol, lactones, etc.), pyrolytic lignin Extractives (e.g., terpenes). Charcoal, Pyrolysis oil. Gases (e.g., CO, CO2, CH4)... [Pg.346]

The third family (c. in Figure 9.1) less widespread, derived from the alkylphenols, offers as with the succinimides several possibilities of modification to the ratio of hydrophilic and lipophilic groups. Mannich s reaction of the alkyl-phenols also provides additives for lubricating oils. [Pg.349]

The above is a general procedure for preparing trialkyl orthophosphates. Similar yields are obtained for trimethyl phosphate, b.p. 62°/5 mm. triethyl phosphate, b.p. 75-5°/5 mm. tri-n-propyl phosphate, b.p. 107-5°/5 mm. tri-Mo-propyl phosphate, b.p. 83-5°/5 mm. tri-wo-butyl phosphate, b.p. 117°/5-5 mm. and tri- -amyl phosphate, b.p. 167-5°/5 mm. The alkyl phosphates are excellent alkylating agents for primary aromatic amines (see Section IV,41) they can also be ua for alkylating phenols (compare Sections IV,104-105). Trimethyl phosphate also finds application as a methylating agent for aliphatie alcohols (compare Section 111,58). [Pg.304]

Alkyl aryl ether Hydrogen halide A phenol Alkyl halide... [Pg.1018]

I ovolac Synthesis and Properties. Novolac resins used in DNQ-based photoresists are the most complex, the best-studied, the most highly engineered, and the most widely used polymers in microlithography. Novolacs are condensation products of phenoHc monomers (typically cresols or other alkylated phenols) and formaldehyde, formed under acid catalysis. Figure 13 shows the polymerization chemistry and polymer stmcture formed in the step growth polymerization (31) of novolac resins. [Pg.120]

The most important appHcation of metal alkoxides in reactions of the Friedel-Crafts type is that of aluminum phenoxide as a catalyst in phenol alkylation (205). Phenol is sufficientiy acidic to react with aluminum with the formation of (CgH O)2Al. Aluminum phenoxide, when dissolved in phenol, greatiy increases the acidic strength. It is beheved that, similar to alkoxoacids (206) an aluminum phenoxoacid is formed, which is a strong conjugate acid of the type HAl(OCgH )4. This acid is then the catalyticaHy active species (see Alkoxides, metal). [Pg.564]

Detergents are metal salts of organic acids used primarily in crankcase lubricants. Alkylbenzenesulfonic acids, alkylphenols, sulfur- and methjiene-coupled alkyl phenols, carboxyUc acids, and alkylphosphonic acids are commonly used as their calcium, sodium, and magnesium salts. Calcium sulfonates, overbased with excess calcium hydroxide or calcium carbonate to neutralize acidic combustion and oxidation products, constitute 65% of the total detergent market. These are followed by calcium phenates at 31% (22). [Pg.242]

Both thermooxidation and photooxidation of polyolefins can be prevented by using the same antioxidants as those employed for the stabilization of polypropylene, ie, alkylated phenols, polyphenols, thioesters, and organic phosphites in the amount of 0.2—0.5% (22,25). [Pg.426]

Nonene, or propylene tetramer, is used to alkylate phenol, which is subsequently ethoxylated to produce nonylphenol ethoxylate, an efficient, rehable industrial surfactant. [Pg.441]

Alkyl hydroperoxides can be Hquids or soHds. Those having low molecular weight are soluble in water and are explosive in the pure state. As the molecular weight increases, ie, as the active oxygen content is reduced, water solubiUty and the violence of decomposition decrease. Alkyl hydroperoxides are stronger acids than the corresponding alcohols and have acidities similar to those of phenols, Alkyl hydroperoxides can be purified through their alkali metal salts (28). [Pg.103]

Substituted Phenols. Phenol itself is used in the largest volume, but substituted phenols are used for specialty resins (Table 2). Substituted phenols are typically alkylated phenols made from phenol and a corresponding a-olefin with acid catalysts (13). Acidic catalysis is frequendy in the form of an ion-exchange resin (lER) and the reaction proceeds preferentially in the para position. For example, in the production of /-butylphenol using isobutylene, the product is >95% para-substituted. The incorporation of alkyl phenols into the resin reduces reactivity, hardness, cross-link density, and color formation, but increases solubiHty in nonpolar solvents, dexibiHty, and compatibiHty with natural oils. [Pg.292]

The in situ process is simpler because it requires less material handling (35) however, this process has been used only for resole resins. When phenol is used, the reaction system is initially one-phase alkylated phenols and bisphenol A present special problems. As the reaction with formaldehyde progresses at 80—100°C, the resin becomes water-insoluble and phase separation takes place. Catalysts such as hexa produce an early phase separation, whereas NaOH-based resins retain water solubiUty to a higher molecular weight. If the reaction medium contains a protective coUoid at phase separation, a resin-in-water dispersion forms. Alternatively, the protective coUoid can be added later in the reaction sequence, in which case the reaction mass may temporarily be a water-in-resin dispersion. The protective coUoid serves to assist particle formation and stabUizes the final particles against coalescence. Some examples of protective coUoids are poly(vinyl alcohol), gum arabic, and hydroxyethjlceUulose. [Pg.298]

Phenol. Phenol monomer is highly toxic and absorption by the skin can cause severe blistering. Large quantities can cause paralysis of the central nervous system and death. Ingestion of minor amounts may damage kidneys, Hver, and pancreas. Inhalation can cause headaches, dizziness, vomiting, and heart failure. The threshold limit value (TLV) for phenol is 5 ppm. The health and environmental risks of phenol and alkylated phenols, such as cresols and butylphenols, have been reviewed (66). [Pg.302]

The resins can be a novolak—hexa or a resole—novolak blend. In some appHcations Hquid resoles are used. Addition of alkylated phenol, oil, or cashew nutsheU Hquid (CNSL) reduces hardness and increases abrasion resistance. Modification by mbber improves the coefficient of friction and reduces brake fading. [Pg.305]

Laminates. Laminate manufacture involves the impregnation of a web with a Hquid phenoHc resin in a dip-coating operation. Solvent type, resin concentration, and viscosity determine the degree of fiber penetration. The treated web is dried in an oven and the resin cures, sometimes to the B-stage (semicured). Final resin content is between 30 and 70%. The dry sheet is cut and stacked, ready for lamination. In the curing step, multilayers of laminate are stacked or laid up in a press and cured at 150—175°C for several hours. The resins are generally low molecular weight resoles, which have been neutralized with the salt removed. Common carrier solvents for the varnish include acetone, alcohol, and toluene. Alkylated phenols such as cresols improve flexibiUty and moisture resistance in the fused products. [Pg.306]

The phosphonate esters, HP(=0(OR)2, of alkylated phenols are used extensively as lubricating-oil additives to control bearing corrosion and oxidation, and to impart antimst properties as stabilizers, as antioxidants (qv) and flame retardants in plastics, as specialty solvents, and as intermediates (see Corrosion AND corrosion control Heat stabilizers). [Pg.368]

Alkylated phenol derivatives are used as raw materials for the production of resins, novolaks (alcohol-soluble resins of the phenol—formaldehyde type), herbicides, insecticides, antioxidants, and other chemicals. The synthesis of 2,6-xylenol [576-26-1] h.a.s become commercially important since PPO resin, poly(2,6-dimethyl phenylene oxide), an engineering thermoplastic, was developed (114,115). The demand for (9-cresol and 2,6-xylenol (2,6-dimethylphenol) increased further in the 1980s along with the growing use of epoxy cresol novolak (ECN) in the electronics industries and poly(phenylene ether) resin in the automobile industries. The ECN is derived from o-cresol, and poly(phenylene ether) resin is derived from 2,6-xylenol. [Pg.53]

In 1957 a procedure was described that selectively alkylated phenol in the ortho position (7). This approach, using aluminum catalysis, made a variety of 2,6-dialkylphenols accessible. The mechanism proposed for this ortho alkylation is outlined as follows ... [Pg.59]

Several methods are available to supplement the phenol alkylations described above. Primary alkylphenols can be produced using the more traditional Friedel-Crafts reaction. Thus an -butylphenol can be synthesized direcdy from a butyl haUde, phenol, and mild Lewis acid catalyst. Alternatively, butyryl chloride can be used to acylate phenol producing a butyrophenone. Reduction with hydrazine (a Wolff-Kishner reduction) generates butylphenol. [Pg.59]

Propoxylates, ethoxylates, and mixed alkoxylates of aUphatic alcohols or alkyl phenols are sulfated for use in specialty appHcations. [Pg.83]

In alkylation, phenols and amines are alkylated by sulfites in high yield and quaternary salts readily form (67). Ethylene sulfite reacts yielding hydroxyethyl derivatives and SO2 elimination, corresponding to its activity as an ethylene oxide precursor (68). [Pg.200]

Commercial Antioxidants Table 4 includes the main classes of antioxidants sold in the United States and the suppHer s suggested apphcations. Some of these are mixtures rather than single substrates. This is especially tme of alkylated amines and alkylated phenols. The extent of alkylation and the olefins used for alkylation can vary among manufacturers. Table 4 is not a complete listing of available antioxidants in the United States. [Pg.234]

The terminal R groups can be aromatic or aliphatic. Typically, they are derivatives of monohydric phenoHc compounds including phenol and alkylated phenols, eg, /-butylphenol. In iaterfacial polymerization, bisphenol A and a monofunctional terminator are dissolved in aqueous caustic. Methylene chloride containing a phase-transfer catalyst is added. The two-phase system is stirred and phosgene is added. The bisphenol A salt reacts with the phosgene at the interface of the two solutions and the polymer "grows" into the methylene chloride. The sodium chloride by-product enters the aqueous phase. Chain length is controlled by the amount of monohydric terminator. The methylene chloride—polymer solution is separated from the aqueous brine-laden by-products. The facile separation of a pure polymer solution is the key to the interfacial process. The methylene chloride solvent is removed, and the polymer is isolated in the form of pellets, powder, or slurries. [Pg.270]

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. [Pg.933]


See other pages where Phenols alkylated phenol is mentioned: [Pg.205]    [Pg.242]    [Pg.221]    [Pg.205]    [Pg.242]    [Pg.221]    [Pg.129]    [Pg.304]    [Pg.1010]    [Pg.259]    [Pg.266]    [Pg.59]    [Pg.69]    [Pg.524]    [Pg.370]    [Pg.189]    [Pg.333]    [Pg.476]    [Pg.669]    [Pg.875]    [Pg.927]    [Pg.933]   
See also in sourсe #XX -- [ Pg.28 ]




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ALKYLATION OF ALCOHOLS AND PHENOLS

Alkoxylated alkyl phenol formaldehyde

Alkoxylated alkyl phenol formaldehyde condensates

Alkyl Phenol Disulfide

Alkyl aryl ethers phenols

Alkyl iodides phenols

Alkyl methyl carbonates, phenol

Alkyl methyl carbonates, phenol reactions

Alkyl phenol ethoxy late

Alkyl phenol ethoxylates

Alkyl phenol ethoxylates Biodegradability

Alkyl phenol formaldehyde resin

Alkyl phenol oxyethylated ester

Alkyl phenol resins

Alkyl phenol-formaldehyde compounds

Alkyl phenols

Alkyl phenols, Hindered

Alkyl subs phenols

Alkyl sulfonic acid esters of phenol

Alkylated phenol feedstocks

Alkylation 2-ethoxy phenol

Alkylation of phenol and enol

Alkylation of phenolates

Alkylation of phenols

Alkylation phenolic derivatives

Alkylation phenols

Alkylation phenols

Alkylation reactions phenols with alkyl halides

Alkylation with phenol

Alkylations phenol

Allylic alkylation phenols

C-Alkylation of Phenolate Anions

C-Alkylation phenols

C-Alkylations of phenolates

Dehydration, phenol alkylation

Friedel-Crafts alkylation of phenols

Friedel-Crafts alkylations free phenols, alkylation

Higher alkyl phenols

Methylol-terminated p-alkyl-substituted phenol

Nucleophilic substitution phenolic oxygen alkylation

O-Alkylation of phenols

Oxidation alkyl substituted phenols with

P-alkyl phenol

Phenol Friedel Crafts alkylation

Phenol alkylated

Phenol ethers, alkylation

Phenol ring-alkylated, formation

Phenol, Cresols and Other Alkyl Phenols

Phenol, alkylation with allyl bromide

Phenol, ruthenium-catalyzed alkylation

Phenolic alkaloids, alkylation with

Phenolic alkylation

Phenolic alkylation

Phenols =* alkyl benzenes

Phenols alkyl halides

Phenols alkyl sulphates

Phenols alkyl-substituted

Phenols alkylation with isobutene

Phenols base-catalyzed alkylation

Phenols ortho alkylation

Phenols, alkylation table

Phenols, alkylation thiocyanation

Phenols, from alkyl benzenes

Potassium phenolate, alkylation with

Supercritical water phenol alkylation

Water phenol alkylation

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