Phenolic resins commercially available

Properly end-capped acetal resins, substantially free of ionic impurities, are relatively thermally stable. However, the methylene groups in the polymer backbone are sites for peroxidation or hydroperoxidation reactions which ultimately lead to scission and depolymerisation. Thus antioxidants (qv), especially hindered phenols, are included in most commercially available acetal resins for optimal thermal oxidative stabiUty. 

Polynuclear Phenol—Glycidyl Ether-Derived Resins. This is one of the first commercially available polyfunctional products. Its polyfunctionahty permits upgrading of thermal stabiUty, chemical resistance, and electrical and mechanical properties of bisphenol A—epoxy systems. It is used in mol ding compounds and adhesives. 

There are now commercially available a large range of laminated plastics materials. Resins used include the phenolics, the aminoplastics, polyesters, epoxies, silicones and the furane resins, whilst reinforcements may be of paper, cotton fibre, other organic fibres, asbestos, carbon fibre or glass fibre. Of these the phenolics were the first to achieve commercial significance and they are still of considerable importance. 

Prior to 1890, formaldehyde was not commercially available [2]. Thus the first phenol-formaldehyde resins were made using formaldehyde equivalents such as methylene diacetate or methylal [2,20]. The first true phenol-formaldehyde resin was made by Kleeberg at the direction of Emil Fisher in 1891 [2,21]. Saliginen (o-hydroxymethyl phenol) was recognized as a condensation product of phenol and formaldehyde in 1894 and was the subject of United States patents in 1894 and 1896 [22,23]. 

The use of the phenyl phosphate group as both a solid support attachment site and a crucial binding element represents what has been referred to as a pharmacophore-linking strategy [26]. We explored a variety of phenyl phosphate tether functionalities to provide resins varying in substitution pattern and in chemical flexibility (Scheme 1 and Table 4) [22]. All phenyl phosphate resins were synthesized in batch quantities of 20 g or more. Resin synthesis began with the addition of either /mnethoxy-benzyl alcohol or benzyl alcohol to commercially available bis(diisopro-pylamino)chlorophosphine, followed by addition of the diversity phenol [(Ri)-OFl, DIAT (diisopropylamino tetrazole)]. Displacement of the... 

Most carbon fibers use PAN as their precursor however, other polymer precursors, such as rayon [8], pitch (a by-product of petroleum or coal-coking industries), phenolic resins, and polyacetylenes [6,7], are available. Each company usually uses different precursor compositions for its products and thus it is difficult to know the exact composition used in most commercially available carbon fiber products. 

Epoxy Resins or Epoxies. The commercially available materials of this glass are usually derived from epichlorohydrin and bis phenol A (See under Epon Resins). Before curing they are viscous liquids or clear, brittle solids... 

Various diazonium salts have been prepared using this approach55 and thermoanalytically characterized.56 Both the structure of the diazonium moiety and the counterion clearly influence the stability of the diazonium moiety. The thermally stable diazonium ion 71 (Z = Cl, Y = CH20) [ty2 (25°) > 100 days] is also capable of scavenging various nucleophiles (amines, phenols, and anilines).57 This resin with a tetrafluoroborate counterion (resin 66) is called T2 diazonium resin and it is now commercially available from Novabiochem. 

Epoxy-phenolic adhesives are made by blending epoxy resins with phenolic resins to improve the high-temperature capabilities of the standard epoxy resins. Developed in the early 1950s, they were the first high-temperature epoxy adhesives to become commercially available.2,3... 

The Influence of the Matrix Precursor. The first requirement for a suitable matrix precursor is high carbon yield, which must be achievable under simple pyrolysis conditions. Figure 14 (left-hand side) shows weight loss as a function of pyrolysis temperature for several matrix precursors practical precursors that are commercially available include coal-tar and petroleum pitches, phenolic resins, polyimides, and the para-polyphenyleneacetylene resin Hercules HA 43 (35,36) The structural formulas of some polymer binders are shown in Figure 15. 

Copolymers of furfural with phenol or phenol-formaldehyde polymers have been available commercially for many years. Since the acid-catalyzed reaction of furfural and phenol has been difficult to control, most industrial applications involve the use of alkaline catalysts. Furfural-phenol resins are used for their alkali resistance, enhanced thermal stability, and good electrical properties compared to phenol-formaldehyde resins. 

Further, the use of commercially available PS-PPha resin combined with microwave condition to lead to a variety of benzoxazoles (xLv) in high purities and yields was given by Wang et al. [71]. The protocol involved a one-step reaction of carboxylic acid with 2-amino phenols. 

Several DUV resists based on phenolic resins sensitized with azide compounds are now commercially available from Hitachi Chemical (RD2000N) (90), Hunt Chemical (WX303) 91), and Tokyo Ohka Kogyo (ODUR120). 

Other phenol derivatives that are used to form the backbone of an epoxy resin include bisphenol E, bisphenol F, resorcinol, brominated bisphenols, and more highly functionalized molecules such as tetrakisphenylolethane. Alcohols, amines, and carboxylic acids may be combined with epichlorohydrin to give a range of diglycidyl ether based epoxy resins. Non-aromatic, commercially available epoxides are produced by peracid epoxidation of alkenes and dienes, such as vinyl cyclohexene and esters of cyclohexane carboxylic acids [23]. The chemical formulas for two common uncured polymers are shown below ... 

Materials used were the standard commercially available grades. "CARDOLITE" Brand NC-513 is 3M s monofunctional epoxy reactive diluent CR-100, 3M s flow control agent DC-200, Dow-Corning antifoam Cab-O-Sil, Cabot fumed silica Epon 1001-X-75, Shell solid epoxy resin as 75% solution in xylene Tint-Ayd( ) EP-30-01, Daniels predispersed titanium dioxide liquid epoxy resin, standard bis-phenol-A diglycidyl ether of epoxide equivalent weight 190 grams/equivalent. 

Chemical stability of the m-bromo phenol containing epoxy resin was compared with commercially available brominated resins. Epoxy resins were refluxed in N-methyl-pyrrolidinone with 1 N KOH for 15 minutes. Results in Table IV clearly demonstrated the extraordinary chemical stability of the m-bromo-phenol containing epoxy resin over the commercial product. 

Commercially available resins are preloaded (e.g. with amino acids, alcohols, phenols, diamines). 

A cresol novolac resin has been synthesized which exhibits a much greater dissolution-inhibiting effect than in various commercially available novolac or phenolic resins. Using this resin, a positive electron beam resist was prepared and its exposure characteristics were examined. A tetramethylammonium hydroxide aqueous solution was used as the developer. The sensitivity reaches 3xl0 6 C/cm2 without post-exposure baking. It was found that the sensitivity to double exposure was much higher than that to single exposure with the same total dose. A similar phenomenon was also... 

Coating solvents were investigated for composite systems of PMPS and various commercially available phenolic or novolac resins. It was found that most of novolac or phenolic resins containing PMPS can form homogeneous films when isoamyl acetate is used as a coating solvent. 

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