Epoxy novolac 4,4 - -bisphenol

Bisphenol A Epoxy Novolacs. Bisphenol A novolacs are produced by reacting bisphenol A and formaldehyde with acid catalysts. Epoxidation of the bisphenol A novolacs gives bisphenol A epoxy novolac (BPAN) with improved thermal properties such asTg, Td of the epoxy-based electrical laminates. 

Bisphenol A-derived epoxy resins, 10 356 Bisphenol A epoxy novolacs, 10 370 Bisphenol A manufacture, microporous catalysts and, 14 420 Bisphenol A moiety, 10 355-356 Bisphenol A polycarbonate (BPA-PC),... 

Epoxy syntactic foams are the best known representatives of this type of material. The brands manufactured in the USSR are EDS (with glass microspheres), EDM (with phenol microspheres). Dienic, novolac, bisphenolic, and esteric structured epoxy resins are used... 

In addition to the DGEB A resins, there are several other types of epoxy resins of commercial significance. The most common of these are epoxy novolacs, glycidyl ether of tetraphe-nolethane, bisphenol F-based resins, and aliphatic and cycloaliphatic resins. 

The epoxy novolac resins are synthesized by reaction of phenolic or cresol novolacs with epichlorohydrin in the same fashion as the bisphenol A resins. The number of epoxy groups per molecule is dependent on the number of hydroxyls in the phenol novolac molecule and to the extent to which they are reacted. Complete epoxidation can be accomplished, but this will lead to steric factors, which could limit the useful size of the cured polymer. Thus, selective epoxidation is often practiced.9... 

Many types of epoxy resins can be used in adhesive formulations. These are characterized in Table 4.1. The most commonly used type is the resin-based diglycidyl ether of bisphenol A (DGEB A). Epoxy novolac, flexible epoxy, high-functionality, and fihu-forming epoxy resins are also used in specialty applications. 

For maximum heat resistance, pyromellitic dianhydride is often used. The composition and properties of metal-to-metal adhesives based on a combination of epoxy novolac and a bisphenol A epoxy resin have been described in Sec. 12.5.1. Depending on the cure temperature and the choice of amine curing agent, strength as high as 3000 psi at room temperature and over 1000 psi in the range of-55 to + 150°C is possible. 

Effects of Epoxy Type and Amount. Three different types of epoxies were investigated, two of them more extensively. The epoxies were 1) a bis(glycidyl ether) of bisphenol A (DER 330, Dow Chemical), 2) an epoxy novolac (DEN 431, Dow Chemical Co.), and 3) a tetra-functional epoxy, tetraglycidyl ether of 4,4 -methylene bis(aniline), (Araldite MY720, Ciba-Geigy Co.). The tetrafunctional liquid epoxy was eliminated early in the study due to the fact that too much stiffness and therefore very little loss (i.e. low damping) was imparted into the IPN. It was believed that the use of the tetrafunctional epoxy resulted in too high a crosslink density in the IPN. 

The repeat unit of bisphenol F epoxy resins (Figure 2.3) or epoxy novolac resin does not significantly increase the epoxy equivalent weight although viscosity and functionality do increase (Helfad, 1996). 

In electronic encapsulation applications, epoxy derivatives of novolacs containing meta-bromo phenol have exhibited substantially better physical and performance properties compared to the conventional tetrabromo bisphenol-A epoxies and brominated epoxy novolacs. The meta-bromo phenol moiety contributes the expected improvements in thermal and hydrolytic stability to the formulation while providing fire retardancy properties (13). 

Epoxy molding compounds, used to encapsulate microelectronic devices, contain bromine to provide flame retardancy to the package. This bromine, typically added as tetrabromo bisphenol-A or its epoxy derivative, has been found to contain many hydrolyzable bromides. These bromides, along with the presence of chloride impurities, are detrimental to the life of the electronic component. Bromine especially has been suspected (proven) to cause wire bond failure when subjected to moisture and/or high temperatures. With the addition of a more thermally and hydrolytic stable bromine compound, flame retardancy does not have to be compromised to increase the device reliability. Stable brominated cresol epoxy novolac, when formulated into a microelectronic encapsulant, increases the reliability of the device without sacrificing any of the beneficial properties of present-day molding compounds. 

Celanese Epi-Rez SU-8 was chosen for these studies. This resin is a polyfunctional epoxy novolac resin (Scheme 2) made from bisphenol-A. It is optically... 

Expanded materials with excellent high-temperature properties are obtained when cresol novolacs are used as hardeners. A typical formulation is based on mixtures of bisphenol A resins and epoxy novolac resins which are cured by cresol novolacs and accelerated by suitable nitrogen-containing agents. 

Generally, a vinyl ester could be classified as methyl acrylic acid extended bisphenol A epoxy, acrylic acid bisphenol E epoxy, a bisphenol F novolac epoxy, or a urethane modified ester. Each will provide a different degree of resistance. Vinyl ester lining systems have been successfully applied to provide protection to stack liners, ducting, scrubbers, thickener tanks, and other vessels in FGD plants, stacks and ducts, electrostatic precipitators, and bag house environments. 

Compounds are available formulated on epoxy novolac-based resins and bisphenol epoxies. The latest bisphenol-A compounds offer high mechanical properties at a cost saving, in comparison with novolacs. Especially at glass contents of over 35 wt%, VE SMC offers advantages over isopolyester SMC. Under stress, SMC/BMC parts with low glass content show initiation at a higher elongation (2.2%) than equivalent... 

In all cases, the resins used were Derakane epoxy vinyl esters (Fig. 9.4). In 64% of the cases the resin was one of the higher temperature type, that is an epoxy novolac vinyl ester resin (Derakane 470). This resin is particularly effective in containing acids and organic solvents. Its HDT of 150°C renders it the resin of choice for the higher temperature applications. Bisphenol A epoxy vinyl ester resins (Derakane 411) were used for 25% of the vessels, in particular for the high pH caustic and hypochlorite streams. The brominated epoxy vinyl esters (Derakane 510) were used for the remainder (11%) of the GRP vessels. These resins are important when both fire... 

Chem. Descrip. Bisphenol F-based epoxy novolac resin Uses Epoxy for high-solids and solv.-free industrial maintenance coatings, chem.-resist. flooring, groufs, and high-temp, adhesives and laminates inc. crosslink dens, and chem. resist, of ambient cured systems Properties Gardner 1 iiq. sp.gr, 1.19 dens. 9.9 Ih/gal vise. 16,000cps EEW 175 100% solids Epotuf 91-263 [Reichhold]... 

Chem. Deserp. One-part, water-based epoxy resin with conosion inhibitors Bisphenol /Vepichlorohydrin epoxy (< 10%), bisphenol A novolac epoxy resin (< 10%), ethanol (2-10%), propylene glycol (5-15%), carbo) zircoaluminate sol n. (< 5%), etc. 

Araldite GY308. See Epoxy, bisphenol F Araldite GY 1180. See Epoxy-novolac Araldite GY 1823. See Epoxy resin Araldite GY2600. See Epoxy, bisphenol A/epichlorohydrin... 

Araldite PT 810. SeeTriglycidyl isocyanurate Araldite PY 258. See Epoxy-novolac Araldite PY 306. See Epoxy, bisphenol F Araldite PY 307-1. See Epoxy-novolac Araldite PY 322. See Epoxy, bisphenol A Araldite PY323. See Epoxy cresol novolac Araldite PY340-2. See Epoxy resin Araldite PZ 3917. See Epoxy cresol novolac Araldite RD-1. See Butyl glycidyl ether Araldite RD-2. See 1,4-Butanediol diglycidyl ether... 

Epolite 9925 Epolite 9935. See Epoxy resin Epomin P-1000. See PEI-1750 Epomin SP-006. See PEI-15 Epomin SP-012. See PEI-30 Epomin SP-018. See PEI-45 EPON HPT Resin 1077. See Tetraglycidyl-4,4 -methylene dianiline EPON HPT Resin 1079. See Epoxy resin EPON Resin 164. See Epoxy cresol novolac EPON Resin 825 EPON Resin 826 EPON Resin 828. See Epoxy, bisphenol A EPON Resin 832. See Epoxy resin EPON Resin 1001F EPON Resin 1002F EPON Resin 1004F EPON Resin 1007F EPON Resin 1009F. See Epoxy, bisphenol A EPON Resin 1031. See Epoxy-novolac EPON Resin 1183. See Epoxy resin, brominated... 

PVM/MA copolymer, isopropyl ester binder, polyester Epoxy-novolac binder, polyester cloth Bisphenol A diglycidyl ether binder, polymerization Polyvinyl alcohol (partially hydrolyzed) binder, poultry prods Transglutaminase binder, precision casting Silica, colloidal binder, pressed powders Cl2-15 alkyl benzoate Cetyl lactate Cetyl palmitate Diisopropyl dimer dilinoleate Hydrogenated vegetable oil Isopropyl isostearate Isostearyl neopentanoate Isostearyl palmitate Isostearyl stearoyl stearate Lanolin wax Lauryl lactate Myristyl myristate Myristyl stearate Octyl palmitate PPG-20 methyl glucose ether distearate Synthetic wax Trihydroxystearin binder, primers... 

Epoxy-novolac resin n. A two-step resin made by reacting epichlorohydrin with a phenol-formaldehyde condensate. Such resins are also known as thermoplastic, B-stage phenohc resins that are in a state of partial cure. Whereas bisphenol-based epoxy resins contain up to two epoxy groups per molecule, the epoxy novolacs may have seven or more such groups, producing more tightly crossHnked structures in the cured resins. Thus they are stronger and superior in other properties. 

Epoxy resins have proven very popular because of their versatility, excellent adhesion, low cure shrinkage, good electrical properties, compatibility with many other materials, resistance to weathering and chemicals, dependability, and ability to cure under adverse conditions. The most widely used epoxy resins in the casting field are the bisphenol-A and cycloaliphatic epoxies. Novolac epoxy resins have higher heat deflection temperatures, but they require high-temperature cure. The novolacs also have excellent resistance to solvents and chemicals. Epoxy castings are often used in electrical/electronic applications. (5ee also epoxy resin.)... 

Branched epoxies (37) are prepared by advancing LER with bisphenol A in the presence of epoxy novolac resins. Such compositions exhibit enhanced thermal... 

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