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Alkyl phenol formaldehyde resin

Figure 3.5 IR spectra of (a) polyamide 6,66,610 (LPA), (b) alkyl phenol formaldehyde resin (PR), (c) reaction product PR/LPA, (d) HR, (e) IIR-PR-LPA copolymer... Figure 3.5 IR spectra of (a) polyamide 6,66,610 (LPA), (b) alkyl phenol formaldehyde resin (PR), (c) reaction product PR/LPA, (d) HR, (e) IIR-PR-LPA copolymer...
Alkyl-phenol formaldehyde resin. See Phenolic resin... [Pg.968]

Synonyms Alkyl-phenol formaldehyde resin A-stage resin Novolac resin Novolak resin One-stage resin PF Phenol-formaldehyde Phenol-... [Pg.1268]

Ludwig used high performance liquid chromatography to determine oligomers in p-alkyl phenol-formaldehyde resins. [Pg.37]

Sulfur cross-links have limited stability at elevated temperatures and can rearrange to form new cross-links. These results in poor permanent set and creep for vulcanizates when exposed for long periods of time at high temperatures. Resin cure systems provide C-C cross-links and heat stability. Alkyl phenol-formaldehyde derivatives are usually employed for tire bladder application. Typical vulcanization system is shown in Table 14.24. The properties are summarized in Tables 14.25 and 14.26. [Pg.433]

Certain alkyl-substituted phenol-formaldehyde resins can act as dispersants for asphalts and asphaltenes in crude oils [1681]. The dispersants help keep asphalt and asphaltenes in dispersion and inhibit fouling, precipitation, and buildup in the equipment. [Pg.315]

Phenol-formaldehyde resins find numerous applications in such areas as wood composites, fiber bonding, laminates, foundry resins, abrasives, friction and molding materials, coatings and adhesives, and flame retardants (JL). From a specialty chemicals standpoint, they are also used as developer resins in carbonless papers (2.). Conventional methods of preparation involve condensation of a phenol with formaldehyde under either acidic (novolak) or basic (resole) conditions (2). Their typical molecular weight range is from 800-4000 daltons (D) and includes a wide variety of alkyl or aryl substituted phenols (A)- The... [Pg.140]

Friedel-Crafts alkylation of dicyclopentadiene with phenol nsing boron triflnoride-etherate as the catalyst gives 2-[4-(2-hydroxyphenyl)tricyclo[5.2.1.0(2, 6)]dec-8-yl]phenol, which can be used in the preparation of the phenol-formaldehyde resins (eqnation 3f. [Pg.608]

Phenol reacts readily with formaldehyde to give trimethylolphenol (2,4,6-tris(hydroxy-methyl)phenol), which undergoes further alkylative polymerization in the presence of acid catalysts (equation 38). Thus-formed phenol-formaldehyde resins (prepolymers) can be used to crosslink a variety of polymers. This is a broad area of industrial significance. [Pg.627]

It is not clear at this stage if the increase in snrface area on grinding is due to the same mechanism responsible for the high surface area of the para-alkyIphenol material. The para-alkyl material is extremely brittle and crumbly in texture, and it seems possible that the reduced functionality of the material has created a system of small domains, which on carbonization behave like finely ground phenol-formaldehyde resin. [Pg.1665]

Attempts have been made over time to improve the physical properties of novolacs. The use of phenol formaldehyde resins prepared in alkaline medium in photoresist compositions is mentioned in a Kalle Co. AG patent. The use of polyvinyl ethers in combination with novolacs to impart stickiness and plasticization action to the latter was patented by Christensen. Steinhoff, Isaacson, and Roelants of the Shipley Company mention the use of vinyl ethers in a patent on roller coating. Lower alkyl polyvinyl ethers, such as methyl, ethyl, butyl, and isobutyl, are added to novolac resins to improve coating flexibility and adhesion to metal surfaces as well as to improve resistance to mildly alkaline solutions. The use of styrene, methyl styrene, and styrene-maleic anhydride copolymers in combination with novolac was mentioned in several patents of both Shipley and Kalle Co. AG. When novolac is copolymerized with maleic anhydride, a resin that is readily soluble in alkaline solutions is obtained. ... [Pg.304]

Reactions with Aldehydes and Ketones. An important use for alkylphenols is in phenol—formaldehyde resins. These resins are classified as resoles or novolaks (see Phenolic resins). Resoles are produced when one or more moles of formaldehyde react with one mole of phenol under basic catalysis. These resias are thermosets. Novolaks are thermoplastic resins formed when an excess of phenol reacts with formaldehyde under acidic conditions. The acid protonates formaldehyde to generate the alkylating electrophile (17). [Pg.60]

The catalyst or add source can consist of ammonium phosphate or polyphosphate salts, phosphoric add-derived amides or alkyl or halo-alkyl phosphates. Charring agents are based on molecular structures that can form cross-linked networks such as pentaerythritol, sorbitol, melamine, and phenol-formaldehyde resins. Other polymeric systems capable of intumescence are some polyamides and polyurethanes. Blowing agents help form a porous structure in the char and can fadlitate its formation. Common blowing agents are based on urea and urea-formaldehyde resins, melamines, and polyamides that can liberate moisture. [Pg.316]

Alkyl phenolic resin n. Phenol-formaldehyde resin in which the phenol used has an alkyl group in the para position. In resins used in coatings, the most common are the tertiary butyl and tertiary amyl phenols. [Pg.41]

Hindered phenol—formaldehyde resins, that is, substituted compounds having at least the ortho positions of the phenyl blocked by alkyl groups, such as bulky branched alkyl groups, have been commercially employed as stabilizers and antioxidant additives in a wide variety of polymers [14-16[. [Pg.497]

Figure 6.15 The phenolic curative (methylol terminated, para-alkyl substituted, phenol-formaldehyde resin) synthesis... Figure 6.15 The phenolic curative (methylol terminated, para-alkyl substituted, phenol-formaldehyde resin) synthesis...
Methylol-terminated para-alkyl-substituted phenol formaldehyde resin is used as the vulcanizing agent for compounds based on butyl and EPDM rubber. The alkyl group is usually octyl. It is commonly used to cure butyl rubber where superior heat resistance is needed. Therefore, this vulcanizing agent is commonly used as the curative to make butyl bladders for repetitive curing of tires. It is also sometimes used in dynamic vulcanization with a tin chloride activator to make thermoplastic vulcanizates (TPVs). [Pg.324]

In acid solution aromatic amines form resins with formaldehyde. This reaction in olves the formation of nuclear methylene linkages similar to those which occur in phenol-formaldehyde resins. The reaction type characteristic of the aromatic nucleus rather than of the activating amine group, whose presence merely facilitates reaction. As a result, resins can be obtained even with tertiary amines such as dimethylaniline. Under these conditions the amine reacts as an ammono-phenol. Studies of the mechanism by which formaldehyde reacU with X-alkyl anilines in acid elution indicate that the primary reaction involves the nitrogen atom. [Pg.204]

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 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]

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]

An alternative copolymerization is illustrated by the method of Blasius. In this preparation, a phenol-formaldehyde (novolac) type system is formed. Monobenzo-18-crown-6, for example, is treated with a phenol (or alkylated aromatic like xylene) and formaldehyde in the presence of acid. As expected for this type of reaction, a highly crosslinked resin results. The method is illustrated in Eq. (6.23). It should also be noted that the additional aromatic can be left out and a crown-formaldehyde copolymer can be prepared in analogy to (6.22). ... [Pg.278]


See other pages where Alkyl phenol formaldehyde resin is mentioned: [Pg.94]    [Pg.603]    [Pg.582]    [Pg.94]    [Pg.603]    [Pg.582]    [Pg.288]    [Pg.19]    [Pg.288]    [Pg.136]    [Pg.160]    [Pg.340]    [Pg.470]    [Pg.42]    [Pg.19]    [Pg.606]    [Pg.2092]    [Pg.372]    [Pg.194]    [Pg.627]    [Pg.60]    [Pg.196]    [Pg.3]    [Pg.56]    [Pg.331]   


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Alkyl phenol resins

Alkylation phenols

Formaldehyde resin

Phenol formaldehyd

Phenol resin

Phenol-Formaldehyde (Phenolics)

Phenol-formaldehyde

Phenol-formaldehyde resin

Phenolic alkylation

Phenolic resins

Phenolic-formaldehyde resins

Phenols alkylated phenol

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