Epoxy/epoxies chains, curing agents

Fig.66 Phase diagrams of a symmetric (peo = 0.51, Mn = 2700, Mw/Mn = 1.10) and b asymmetric (0peo = 0.32, Mn = 2100, Mw/Mn = 1.14) PEO-fc-PEP block copolymers blended with epoxy resin. Phase transitions which originate from swelling of PEO chains with epoxy and/or curing agent are drawn as single lines, without implication that there are no coexistence regions. From [197]. Copyright 2001 Wiley...

Uses. 3-Pentenenitrile, 3PN, is used entirely by the manufacturers to make adiponitrile. i7j -2-Pentenenitrile, 2PN, can be cycli2ed catalyticaHy at high temperature to produce pyndine, a solvent and agncultural chemical intermediate. 2PN is also chlorinated to manufacture pentachloropyndine, an intermediate in the insecticide Dursban produced by Dow. Addition of ammonia to 2PN foUowed by reduction leads to 1,3-pentadiamine (Dytek ep), which is used as a curing agent for epoxy coatings and as a chain modifier in polyurethanes. 

This technique involves the dispersion of a nanomaterial in a monomer (Fig. 4.8). This step requires a certain amount of time that depends on the polarity of the monomer molecules, the surface treatment of the nanomaterial, and the swelling temperature. For thermoplastics, the polymerization can be initiated either by the addition of an agent or by an increase in temperature. For thermosets such as epoxies or unsaturated polyesters, a curing agent or peroxide can be added in order to initiate the polymerization. Functionalized nanomaterials can improve their initial dispersion in the monomer and consequently in the composites. In the case of layered materials, such as clays or graphene, the most important step is the penetration of the monomer between the sheets, thus allowing the polymer chains to exfoliate the material. The... 

Most reactive diluents are mono- or difunctional. They are made by reacting epichloro-hydrin with an alcohol, a phenol, or a polyol to produce a mono- or polyglycidyl ether resin. However, there are some nonepoxy diluents that are used as well. These nonepoxy diluents generally react with the curing agent or other functional groups in the epoxy chain. 

In polyaddition, cross-linking occurs by means of chain extension. The majority of ambient-cured construction products are based on this type of reaction, where in situ polymerisation occurs after the epoxy resin base and the curing agent are mixed. The curing agent causes the epoxide or hydroxyl groups to react (Ellis, 1994). 

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