Epoxy toughened

These adhesives are generally based on blends of solid epoxy resins with resole-type phenolic resin. The epoxy resin component is often not the predominant component in the blend, depending on the end properties required. Phenolics are compatible with epoxy resins and will react through the phenolic hydroxyl group. The amount of phenolic resin used is generally much greater than that required to crosslink with the epoxy, so one can debate whether (1) the epoxy toughens the phenolic adhesive or (2) the phenolic increases the heat resistance of the epoxy. 

Farris, R. D., and Steward, S. L., New Epoxy Tougheners Widen the Adhesive Formulation Window, Adhesives and Sealants Industry, January 2002. 

Test TGDDM epoxy Toughened epoxy Amorphous thermoplastic... 

Compatibilized, Segmented Liquid Rubbers as Epoxy-Toughening Agents... 

Ricotaff. [Ricon Resins] Anhydride/q>-oxy system structural adhesive fw polyolefins, elec, applies., epoxy toughener. 

Epoxy toughening additives initially were based on rubbery inclusions or functionalized oligomers (carboxy or amine terminated butadiene/ acrylonitrile copolymers). More recently, impact modifiers (core-shell type) similar to that commonly employed with PVC have been proposed. For composites, tougher epoxy matrix candidates... 

It is believed that this particular two phase morphology is the key to the toughening mechanism of the host matrix (4-9). The success of the epoxy toughening principle by RLP depends vitally on the interaction of the rubber with the epoxy matrix, and on the phase separation mechanism. Control of these two major variables is complex and only partially understood (8,9). Experimental results of the mechanical properties of RLP modified epoxy resins are frequently conflicting, and depend on the preparation techniques of the polymer composites (9,10,11). 

Wu Wu, H., Gopala, A., Harris, F., Heiden, P. Investigation of readily processable thermoplastic-toughened thermosets II. Epoxy toughened using a reactive solvent approach. J. Appl. Polym. Sci. 70 (1998) 935-942. 

Hyd Hydro, R. M., Pearson, R. A. Epoxies toughened with triblock copolymers. J. Polym. Sci. Part B - Polym. Phys. 45 (2007) 1470-1481. 

If too large an elastomer concentration is chosen, no phase separation will occur and there will be no epoxy toughening. 

Modified (or alloyed) epoxy Toughener, nylon, phenolic, polysulfide, resorcinol and phenol formaldehyde, melamine, and urea-formaldehyde... 

Daniel IM, Shareef I, Aliyu AA, Rate effects on delamination fracture toughness of a toughened graphite/epoxy. Toughened Composites, ASTM STP 937, Johnson NJ ed., American Society for Testing and Materials, Philadelphia, 260-274, 1987. 

One-part heat curing paste epoxy adhesives generally contain latent catalysts, liquid epoxies, toughening agents, fillers, thixotropes, and adhesion promoters. 

Significant efforts have been directed toward performance enhancements of epoxy structural composites. Advances have been made in the epoxy-toughening area. Epoxy nanocomposites and nanotube systems have been studied and are claimed to bring exceptional thermal, chemical, and mechanical property improvements. However, commercialization has not yet materialized. 

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