Thermosetting materials epoxies

Thermoset materials Epoxy resins, phenolic resins, polyurethanes (highly cross-linked), anaerobic adhesives. 

As thermosetting materials, epoxy resins can be cured either by anhydride through the condensation reaction mechanism using amine as the catalyst or by cationic... 

The commonly used resins in the manufacture of decorative and industrial laminates ate thermosetting materials. Thermosets ate polymers that form cross-linked networks during processing. These three-dimensional molecules ate of essentially infinite size. Theoretically, the entire cured piece could be one giant molecule. The types of thermosets commonly used in laminates ate phenoHcs, amino resins (melamines), polyesters, and epoxies. 

Thermosetting materials, which have a rigid, cross-linked structure for example, the polyester and epoxy resins. 

In most applications, polyester and vinyl ester resins are used as the matrix materials. Epoxies are also used, although they require longer cure times and do not release easily from the pultrusion dies. Hence, thermosetting resins are most commonly used with pultrusion, although some high-performance thermoplastics such as PEEK and polysulfone can also be accommodated. In addition to the resin, the resin bath may contain a curing agent (initiator, cf. Section 3.3.1.2), colorants, ultraviolet stabilizer, and fire retardant. 

Epoxy adhesives can be manufactured into a film form. This is most conveniently done with solid epoxy resins in solution. Epoxy film adhesives can be thermoplastic (e.g., linear ultrahigh molecular weight phenoxy resin) hot melts, but more commonly they are formulated, thermosetting materials. 

Adhesives commonly used on thermosetting materials include epoxies, urethanes, cyanoacrylates, thermosetting acrylics, and a variety of nonstructural adhesive systems. The following discussion includes a very brief description of various thermosetting substrate materials, the properties that are critical relative to epoxy adhesion, and any special processes that should be noted for the particular substrate. 

Phenolic, Melamine, and Urea. The phenolics are heavily commercialized thermosetting materials that find their way into many applications. They have an excellent combination of physical strength and high-temperature resistance. They have good electrical properties and dimensional stability. Like epoxies and diallyl phthalate, phenolic resins are often found to contain fillers and reinforcement. 

A compound, in the understanding of this chapter, is a thermosetting, thermoplastic, epoxy resin (cold curing) or elastomeric material with or... 

Like the testing variables just described, material variables can influence the fracture behavior of epoxy thermosets. Material variables discussed herein include the types of epoxy resins and amine curatives. 

Thermosetting Foam Substrates Most thermosetting plastics are not particularly difficult to bond. Obviously, solvent cementing is not suitable for bonding thermosets to themselves, since they are not soluble. In some cases solvent solutions can be used to join thermoplastics to thermosets. In general, adhesive bonding is the only practical method of joining a thermoset to itself or to a non-plastic material. Epoxies or modified epoxies are the most widely used adhesives for thermosets (1). 

One possible version of the LCT concept involves the design and preparation of new monomers consisting of a rigid rodlike central unit, a characteristic of conventional liquid crystals, capped at both ends with well known crosslinking groups. The crosslinking groups were chosen from the common functionalities used for thermoset materials such as epoxy, maleimide, acetylene, etc. This... 

Since the introduction of the first commercial thermoset, Bakelite, based on phenol formaldehyde condensation, a wide range of thermoset materials have been introduced. These are typically designed for specific properties related to their chemistry and processability. Some commercially important thermosets include phenolics, ureas, melamines, epoxy resins, unsaturated polyesters, silicones, rubbers, polyurethanes, acrylics, cyanates, polyimides, and benzocyclobutenes. ... 

Polyethylene and polyvinyl chloride and epoxies and phenolics were the most popular thermoplastic and thermoset materials, respectively, of that period. 

Among those plastics which are commercially produced in cellular form are polyurethane, PVC, polystyrene, polyethylene, polypropylene, epoxy, phenol-formaldehyde, urea-formaldehyde, ABS, cellulose acetate, styrene-acrylonitrile, silicone, and ionomers. However, note that it is possible today to produce virtually every thermoplastic and thermoset material in cellular form. In general, the basic properties of the respective polymers are present in the cellular products except, of course, those changed by conversion to the cellular form. 

As most work reported to date on thermosetting layered silicate nanocomposites involves epoxy resins, this review will focus on this class of thermosetting materials. However, some work pubUshed on other thermosets such as vinyl ester resins and imsaturated polyesters will be included where appropriate. 

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