Bisphenol diglycidyl ether, reaction with

Analytically, epoxy groups are determined by the reaction with hydrogen halide and back titration with a standard base. Other functional groups present may cause interference problems and result in poor end points. Pyridinium chloride-pyridine is a recommended reagent for the analysis of bisphenol-diglycidyl ether resins [22,23],... 

Diglycidyl ether of bisphenol XLI was prepared by the reaction of bisphenol with excess ECH followed by dehydro chlorination with solid NaOH. The yield was 92-95% and the oxirane oxygen content was 7.50% (calculated 8.18%). Epoxidation of the diglycidyl ether XLII with PAA at 30-35 °C yielded the trie-... 

Comparable process techniques involving the reaction of bisphenol A diglycidyl ether with methacrylic acid produce the corresponding hydroxy... 

Advancement Process. In the advancement process, sometimes referred to as the fusion method, Hquid epoxy resin (cmde diglycidyl ether of bisphenol A) is chain-extended with bisphenol A in the presence of a catalyst to yield higher polymerized products. The advancement reaction is conducted at elevated temperatures (175—200°C) and is monitored for epoxy value and viscosity specifications. The finished product is isolated by cooling and cmshing or flaking the molten resin or by allowing it to soHdify in containers. 

Bisphenol A causes slight skin and eye irritation. It did not cause contact allergy in a guinea pig maximization test. Furthermore, no cross-reactions were detected when animals sensitized to the diglycidyl ether of bisphenol A were tested with bisphenol A. 

Preparation of a Cured Epoxy Resin by the Room Temperature Reaction of Bisphenol A Diglycidyl Ether with Polyamines... 

Antoon and Koenig 67) found a first-order dependence with respect to the tertiary amine, but they were not able to distinguish between zero-, first-, and second-order kinetics with respect to monomers. Approximately the same fit was obtained for all mentioned orders below the gel point. Peyser and Bascom reported first-order kinetics for the curing of the diglycidyl ether of bisphenol A with hexahydrophthalic anhydride 94) and second-order kinetics with respect to the same epoxide cured with nadic methyl anhydride 93). They also pointed out the uncertainty in determining the reaction order. 

These are mainly derived from the reaction of an epoxy resin, for example, bisphenol A diglycidyl ether, with acrylic or methacrylic acid. Their general formula is ... 

Bisphenol F Resins. Diglycidyl ether resins based on bisphenol F (DGEBF) have been developed to provide cured epoxy resins with greater flexibility and lower softening temperatures than conventional DGEB A epoxy resins. The preparation of bisphenol F resins is from formaldehyde and phenol. Three isomers are possible because substitution can occur at the ortho-, meta-, or para- positions. The proportion of isomers depends upon the pH of the reaction medium. 

Diglycidyl ether of Bisphenol A (DGEBA) is a stiff monomer and in the reaction with aromatic or even aliphatic diamines it exhibits a very low tendency to cyclization, so that the ring-free theory can be applied with success. This conclusion was derived from the fact that the critical conversion at the gel point was independent of dilution for DGEBA-diamine systems and that the critical conversions correspond to the ring-free modelThe same conclusion applies to DGEBA-dicarboxylic acids systems... 

Fig. 12. Viscosity versus reaction time of a sample of Bisphenol-A diglycidyl ether with 2.5% (w/w) hi -benzene) -cyclopentadienyl)-iron(lI)-hexafiuorcq>ho phate after irradiation at 20 °C...

Figure 15.2 (a) Bisphenol A diglycidyl ether, (b) Curing reaction on an epoxy resin with a diamine. 

Table I lists typical properties of a baker s dozen of these resins, produced by typical direct preparations, without extensive purification. Overall, the viscosities of these resins were quite low, particularly by comparison to the well known general purpose epoxy resins based on the diglycidyl ether of bisphenol A (DGEBA). The more shielded higher alkylsubstituted hydantoin rings favored lower viscosities. Some anomalies in these viscosities presumably reflected either a tendency of certain resins to crystallize, or the presence of some species of higher molecular weight, formed by reaction of the glycidyl group with a second hydantoin ring.

Another approach to a diglycidyl ether of this type which results in a product of improved solubility characteristics is the reaction of two moles of a pure diglycidyl ether of Bisphenol-A with one mole of 2,6-divanillylidene cyclohexanone. This results in a resin with glycidyl ether terminals which is partially soluble in ketone solvents, particularly methyl ethyl ketone. 

Phosphonium ylides have previously been used as latent catalysts for the addition of bisphenol A diglycidyl ether with bisphenol A. In their latest contribution to this topic, Endo and co-workers have carried out a detailed kinetic study on the effect of different ylide-substituents on the reaction of glycidyl phenyl ether with 2,6-dimethylphenol (Scheme 24), and the polyaddition of bisphenol A diglycidyl ether with bisphenol A. ... 

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