Epoxy resins, use

In recent years, proprietary catalysts for advancement have been incorporated in precataly2ed Hquid resins. Thus only the addition of bisphenol A is needed to produce soHd epoxy resins. Use of the catalysts is claimed to provide resins free from branching which can occur in conventional fusion processes (10). Additionally, use of the catalysts results in rapid chain-extension reactions because of the high amount of heat generated in the processing. 

A component of polycarbonate plastics and epoxy resins used to line food cans... 

A hard carbon with high capacity can be made from epoxy novolac resin [12]. The epoxy resins used cost about US 2.50 per pound and give pyrolysis yields between 20 and 30%. However, it is well known that phenolic (or phenol-formaldehyde) resins can be pyrolyzed to give hard carbons with a yield of over 50% [42]. In addition, these resins cost about USSl.OO per pound. Phenolic resins therefore offer significant cost advantages over epoxy resins, so we... 

Epoxides are cylic ethers which are highly reactive because of the strained bond angles of a three-membered ring. Because of the high reactivity of epoxides, they are the starting materials for so-called epoxy resins used for high-strength adhesives. 

Epoxy (Amine-Cured) Bisphenol A-based epoxy resins used for composite fabrication are commonly cured with multifunctional primary amines. For optimum chemical resistance these generally require a heat cure or postcure. The cured resin has good chemical resistance, particularly to basic environments, and can have good temperature resistance. 

Figure 3.6 Cross-section (a) and external view (b) of stainless steel HP IR cell used for experiments supercritical fluids. P = fill ports E = epoxy resin, used to seal Cap2 windows. (From Ref [26], reproduced by permission of Wiley-VCH).

Agrawal, J.P., Dev, S.S., Gholap, D.H., Satpute, R.S., Tapaswi, M.A., and Nigde, B.N. (1986) Improvement of Low and High Temperatures Characteristics of Novolac Epoxy Resin Used for Inhibition of HTPB Based Composite Propellants. ERDL Report No. 8/86. 

Eponite" 100. Shell Chemical Co trademark for a water-dispersible liquid epoxy resin used in textile industry to impart crease resistance, shrinkage, etc Ref CondChemDict(1961), 444-R... 

Variable temperature studies of epoxy resins using a spinning device based on the Lowe design have been reported in Reference 5. 

Use as a feedstock for production of epichlorohydrin (via dichloropropanol) for use in production of epoxy resins used in paper reinforcement and water purification treatments... 

As in the cyanate/epoxide compositions, polysulfone is used as an additive in cyanate/epoxide/maleimide systems. As an example, a composition for carbon-fiber composites should be mentioned. It contains BPA/DC-BMI prepolymer, epoxide resin and polyethersulfone [111-113] Zn acetate and dicumyl peroxide are added. Polyethersulfone powder was added to the three-component system with 4,4 -diamino-diphenylmethane-based tetraepoxide as one of the epoxy resins used [114]. 

Accelerators are often used to increase the reactivity of epoxy-anhydride systems. The proper amount of cure accelerator is empirically determined and varies according to the material being used as the accelerator, the anhydride and epoxy resin used, and the desired cure speed and end properties. 

The advantage of this toughening process is that the high modulus and Tg of the epoxy resin are not sacrificed. The Tg of the product is indicative of the epoxy resin used as the matrix, although the precipitated domain has a Tg of about -40 to -50°C. 

Sanjana, Z. N., Selby, R. L. Monitoring cure of epoxy resins using a microdielectrometer, p. 1233, Proc. 29th SAMPE Symp., 1984... 

The most common epoxy resins use a prepolymer made from bisphenol A and epichlorohydrin. 

Fig 11 a-c Epoxy resins used to study epoxy network fracture, (a) DGEBA (diglycidyl ether of Bisphenol A) (b) DGEB (diglycidyl ether of butane diol (c) TGDDM (teraglycidyl of diaminodi-phenyl methane)... 

Resin Components Epoxy resins used in this study were fabricated from the same components employed to prepare most of the commercially available graphite-epoxy prepreg resins used in military aircraft, namely Narmco 5208,... 

D. A. Lewis eta/., The accelerated curing of epoxy-resins using microwave-radiation, Abstracts of Papers of the American Chemical Society, 194, 130-POLY (1987). 

Zeiss [48] describes a method for measuring sections of milled ferrite powder. The powder was mixed in 40 60 volume ratios with epoxy resin using a homogenizing head rotating at 25,000 rpm. The mixture was then poured into a 0.5 in diameter mold and cured at 60°C and 1000 psi to eliminate air bubbles. The casting was then polished in a vibratory polisher using 0.3 and 0.5 pm alumina in water. A photomicrograph of the polished section was used for subsequent analysis. 

Figure 11. Photomicrograph (plane polarized light) of the crystal morphology characteristic of folia. Note the dendritic habit and the very porous nature of the precipitate. The dark material surrounding the crystals is opaque epoxy resin used to impregnate the sample before thin sectioning.

Rees, T.M. and Wilford, A. (1994) The Modern Approach to Modifying Epoxy Resins using Liquid Polysulphides Part 2, Morton International, Coventry, UK. 

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