DGEBA ether

DGEBA. See Bisphenol A, diglycidyl ether. Bisphenol A, diglycidyl ether (DGEBA) [1675-54-3]... 

The pure diglycidyl ether of bisphenol A [1675-54-3] DGEBA is a crystalline soHd (mp 43°C) with a weight per epoxide (WPE) = 170. The typical commercial unmodified Hquid resins are viscous Hquids with viscosities of 11—16 Pa-s (110—160 P) at 25°C, and an epoxy equivalent weight of ca 188. 

The diglycidyl ether (DGEBA) and the polyglycidyl compound (PGCBA) were mixed and heated to about 120 °C. The stoichiometric amount of bisphenol A was dissolved in the resin and, after cooling to about 60 °C, 0,1% by weight of 2-ethyl-4-methyl-imidazol was added to the mixture. The well stirred composition was degassed in a vacuum oven in order to remove trapped air. Afterwards, the reactive mixture was poured into preheated moulds and cured for two hours at 140 °C followed by two hours at 180 °C. 

Diglycidyl ether of bisphenol A (DGEBA, MW 340 Da) and 4,4 -dihydroxy-diphenylmethane (DHDPM, MW 200 Da) were analysed by SEC-MALS [784]. DGEBA and DHDPM are the basic oligomers of epoxy resins and phenol-formaldehyde condensates, respectively, which are widely used in the electronic and automotive industries. Excellent reproducibility ( 1 %) and good accuracy (better than 10%) were observed. SEC has also been used for the determination of mineral oil in extended elastomers [785] and in PS [178]. With heptane containing 0.05% isopropanol as the mobile phase, mineral oil is completely unretained and elutes before the solvent via SEC all other components in a PS extract are retained on silica and elute after the solvent peak. 

CBS, CZ (V-Cyclohexyl-2-benzothiazole DGEBA Diglycidyl ether of bisphenol A... 

Shell s Epon 828, a blend of oligomers of diglycidyl ether of bisphenol A (DGEBA, n=0), was used. 

Dezincing, lead refining by, 14 754-755 DGEBA-aromatic polyamine adduct system, 10 416, 417. See also Diglycidyl ether of bisphenol A (DGEBA)... 

This paper describes the synthesis and characterization of a new zwitterionic water-soluble thiosulfate polymer (Poly[7-(amino -thiosulfate) etheij-PATE) via chemical reaction of a diglicydyl ether of bisphenol A (DGEBA) with aminoethane thiosulfuric acid (AETSA) as a reactive... 

Yamani and Young (5) applied the theory to explain the plastic deformation of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin cured with various amount of triethylene tetramine (TETA). They found that the theory gave a reasonable description for the resins below the glass transition temperatures T. ... 

We have undertaken a systanatic investigation of the effect on cured resin physical properties of various alkyl groups on the MFD aromatic ring. In this report we present static and dynamic mecdaniccd properties, density measurenents, and glass treuisition tenperature (Tg) measuremmits of diglycidyl ether of bisphenol-A (DGEBA) cured with various alkylated MFD s. 

Authors Antonio Moroni et al. [2] (1986) System Resin a mixture of DGEBA (Shell Epon 826), 80%, and diglycidyl ether of... 

Diglycidyl ether of bisphenol-A (DGEBA), epoxy resin (YD 128, Kuk Do Chem., Mn = 378), and bisphenol-A dicyanate (BPACY, Arocy B-10, Ciba-Geigy) were used as the thermoset resin. 4,4 -diaminodiphenyl sulfone (DDS, Aldrich Chem. Co.) was used as a curing agent for epoxy. Polyetherimide (PEI, Ultem 1000, General Electric Co., M = 18,000) and 2-methyl imidazole (2MZ, Aldrich Chem. Co.) were used as the thermoplastic modifier and catalyst. 

The epoxy resin can be defined as any molecule that contains two or more alpha-epoxy groups which can be reacted to form a thermoset system. An example of a difunctional epoxy resin is diglycidyl ether of Bisphenol-A (DGEBA) which is formed... 

It was noted that more refinement in spectral resolution was still needed. The combination of proton enhanced C-13 spectra combined with magic angle spinning made possible the identification of functional groups in the four DGEBA epoxy systems. A peak between 70-73 ppm were evidenced in all four systems indicative of the carboxyl-methine ether carbon of the reacted epoxide groups and adjacent methylene groups. 

The DGEBA based epoxies were reacted with various curing agents. These spectra were than compared to the solution spectra of unreacted epoxy. It was shown that the peaks due to the epoxide carbons were not present in the polymerized DGEBA. In their previous study, Sojka and Moniz 481 showed that DGEBA partially cured with piperidine, exhibited a peak near the methylene peak that increased in intensity and complexity with the curing reaction. This peak was assigned to the carboxyl-methine ether carbon and the methylene carbon near the reaction site. These studies addressed the questions ... 

The complex sorption behavior of the water in amine-epoxy thermosets is discussed and related to depression of the mechanical properties. The hypothesized sorption modes and the corresponding mechanisms of plasticization are discussed on the basis of experimental vapor and liquid sorption tests, differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and dynamic mechanical analysis. In particular, two different types of epoxy materials have been chosen low-performance systems of diglycidyl ether of bisphenol-A (DGEBA) cured with linear amines, and high-performance formulations based on aromatic amine-cured tetraglycidyldiamino diphenylmethane (TGDDM) which are commonly used as matrices for carbon fiber composites. 

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