Epoxy phenol novolacs

Epoxy phenolic can coatings, 18 38 Epoxy phenol novolac (EPN) resins, 10 367-368 toxicity of, 10 461... [Pg.324]

Calculations for a branched advancement synthesis are defined to permit development of well-characterized functionality in the product molecules. In this study, the difunctional epoxy resin monomer used is the diglycidyl ether of bisphenol A, Epon 828, and the multifunctional epoxy phenol novolac resin used is DEN 438. Let ... [Pg.186]

For a series of epoxy phenolic novolac prepolymers cured with bisphenol A, imidazole, or DDS and toughened with 10 per CSR particles, the crosslink density was varied over a wide range of Me from 200 g mol 1 up to 2000 gmoF1 (Lu, 1995). In this series an increase in Me is related to a decrease in... [Pg.421]

Bisphenol F based epoxy resins. Instead of reacting bisphenol A with epichlorohydrin to form a liquid resin, a similar reaction can be conducted with bisphenol F (Figure 2.2). Bisphenol F is composed of a mixture of isomers - ortho-ortho, ortho-para and para-para linkages -whereas bisphenol A is composed mainly of para-para linkages. If n is less than about 0.2, the resins are called bisphenol F epoxides. If n is higher they are referred to as epoxy phenol novolac (EPN) resins (Helfad, 1996). [Pg.28]

Synonyms Epoxy novolac resin Epoxy-phenolic resin Epoxy phenol novolac 2-Phenoxymethyloxirane, compd. with formaldehyde Poly [(phenyl glycidyl ether)-co-formaldehyde... [Pg.1103]

Epoxy novolac resin Epoxy-phenolic resin Epoxy phenol novolac. See Epoxy-novolac... [Pg.1643]

The neat novolac resins are also the precursors in the manufacture of a range of (see Epoxide adhesives), such as epoxy phenol novolacs and epoxy cresol novolacs spoxy resins. [Pg.318]

Another class of epoxy resins is the novolacs, particularly the epoxy cresols and the epoxy phenol novolacs. These are produced by reacting a novolac resin, usually formed by the reaction of o-aesol or phenol and formaldehyde with epichlorohydrin. These highly functional materials are particularly recommended for transfer molding powders, electrical laminates, and parts in which superior thermal properties, high resistance to solvents and chemicals, and high reactivity with hardeners are needed. [Pg.162]

Epoxy NovolaC Resins. Epoxy novolacs are multifunctional epoxies based on phenolic formaldehyde novolacs. Both epoxy phenol novolac resins (EPN) and epoxy cresol novolac resins (ECN) have attained commercial importance (53). The former is made by epoxidation of the phenol-formaldehyde condensates (novolacs) obtained from acid-catalyzed condensation of phenol and formaldehyde (see Phenolic Resins). This produces random ortho- and para-methylene bridges. [Pg.2676]

Table 7. Typical Properties of Epoxy Phenol Novolacs...

Epoxy phenol novolac resins. Acute oral studies indicate low toxicity for these resins. Eye studies indicate only minor irritation in animals. The EPN resins have shown weak skin sensitizing potential in humans. [Pg.2771]

Others include brominated bisphenol A resins which impart fire resistance, epoxy phenol novolac (EPN) resins, bisphenol F epoxy (DGEBF) resins, epoxy cresol novolac (ECN) resins, cycloaliphatic epoxy resins, and tetraglycidyl-4,4 -diaminodiphenylmethane (TGDDM). [Pg.8497]

The three most often used epoxy resins for monolithic surfacings are the bisphe-nol A, bisphenol F (epoxy novolac), and epoxy phenol novolac. These base components are reacted with epichlorhydrin to form resins of varying viscosity and molecular weight. The hardening system employed to effect the cure or solidification will determine the following properties of the cured system ... [Pg.414]

Bisphenol A epoxy is the most popular, followed by the bisphenol F, which is sometimes referred to as an epoxy novolac. The epoxy phenol novolac is a higher viscosity resin that requires various types of diluents or resin blends for... [Pg.414]

Extensive development of both EPM (epoxy phenol novolac) and ECM (epoxy cresol novolac) resins has occurred to improve the quality of the resins by a reduction of ionic and reactive chlorohydrin... [Pg.302]

The same basic epoxy resin systems are used as monolithic surfacings and epoxy polymer concrete. In addition to these, epoxy phenol novolac is also used to produce mortars and grouts. This is a higher viscosity resin that requires the inclusion of various types of diluents and resin blends. Table 10.3 lists the atmospheric corrosion resistance of the mortars and grouts. [Pg.178]

FIGURE 7.6 A multifunctional epoxy phenol novolac resin. [Pg.143]

Being a glycidyl ether of a novolac type phenol formaldehyde resin, epoxy phenol novolac resins (Figure 2.39 (a)) are the polymeric multifunctional counterpart of bisphenol F resin. They are supplied as highly viscous through semisolid to solid resins. They are generally prepared by reacting epichlorohydrin with novolac type phenol formaldehyde resins. [Pg.96]

Figure 2.39 Some multifunctional epoxy resins (a) epoxy phenol novolac,...

Some examples of multifunctional epoxy resins other than epoxy phenol novolac resins are depicted in Figure 2.39 (b), (c) and (d). Triglycidylisocyanurate is a solid trifunctional epoxy cross-linker used in powder coatings, which provides a higher cross-link density and superior photochemical stability compared to BPA epoxy resins. The use of triglycidyl isocyanurate may present toxicity hazards. [Pg.97]

Another important class of modified epoxy resins, known as epoxy acrylates, are reaction products of a low MW epoxy resin and acrylic acid or methacrylic acid, which are used in radiation curable systems. The acrylate functionality is 2, but higher functionality variants can also be prepared by using epoxy phenol novolac in place of BPA epoxy resin. Radiation curable formulations from these oligomers provide a better balance of properties and cost compared to some of the alternative polymer systems. [Pg.101]

Multifunctional epoxy resins such as aromatic glycidyl ether resins and aromatic glycidyl amine resins are commercially available. Commercially important epoxy phenol Novolac resins and epoxy cresol Novolac resins are prepared from excess epichlohydrin and phenol-formaldehyde or o-cresol-formaldehyde resins. The high functionality of these Novolac resins increases crosslink density and improves thermal stability and chemical resistance ... [Pg.15]

Various curing schedules are reported in the patent literature, the best volume resistivity (5.7 x 10 ft cm) being achieved after curing for 24 h at 120 °C and 5 h at 180 °C. It has been claimed that a die attach adhesive composed of an epoxy-phenol novolac system and a catalyst of the Pl P" " BPhJ complex type provides die-shear strengths of 43 and 9 N at 20 and 350 °C, respectively, after curing for 30 s at 250 °C. Thermally conductive adhesives are also prepared by loading epoxy-phenolic compositions wifli crystalline silica powder. [Pg.269]