Curing agents, epoxy polyamides

Ethylenediamines are used in the following products lube oil and fuel additives (20%), chelating agents (16%), wet-strength resins (15%), epoxy curing agents and polyamides (13%), surfactants (10%), oil field chemicals (7%), and miscellaneous (19%). 

Toxicology LC50 (inh., mouse, 4 h) 400 mg/m poison by inh. TSCA listed Hazardous Decomp. Prods. Heated to decomp., emits toxic vapors of NOx Uses Epoxy curing agent amorphous polyamide comonomer Manuf./Distrib. Air Prods. http //www.airproducts.com, Aldrich http //www.sigma-aldrich.com, BASF http //www.basf.com-, Fluka http //www.sigma-aidrich.com... 

Paints, varnishes and lacquers based on epoxy resins are used in various industrial applications because of their strength and durability. Two-component epoxy paints that cure at room temperature need a hardener added before their use. One-component epoxy paints that are heat-cured contain a hardener which can be activated only by heating. Polyfunctional aliphatic amines, aromatic amines, solid polyamides and anhydrides can be used as curing agents. Epoxy-ester-resin paints are formed by reacting epoxy resin with... 

The two-part epoxy adhesive, readily available in hardware stores or other consumer outlets, comes in two tubes. One tube contains the epoxy resin, the other contains an amine hardener. Common diamine room temperature epoxy curing agents are materials such as the polyamides, available under the trade name Versamid. These polyamides are the reaction products of dimer acids and aUphatic diamines such as diethylenetriamine [111-40-0] ... 

The FM 123-2, supplied as a supported film on a knitted mlcro-fllament nylon carrier, was applied directly to one pretreated (SAA or FPL) A1 panel (15 cm x 15 cm x 0.3 cm). A second panel was then pressed onto the exposed adhesive side and the "sandwich structure was subsequently cured at 120°C under 40 psi for 1 hr. A 1 1 1 mixture of the epoxy-polyamide formulation (EPON resin Versamld curing agent thinner, MIL-T-81772) was sprayed onto prepared 7075-T6 specimens to a thickness (dry) of 0.015 - 0.023 cm. 

Curing agents account for much of the potential hazard associated with use of epoxy resins. There are several major types of curing agents aliphatic amines, aromatic amines, cycloaliphatic amines, acid anhydrides, polyamides, and catalytic curing agents. The latter two types are true catalysts, in that they do not participate in the curing process. 

Two curing agents that have found their way into many epoxy adhesive formulations are the polyamides and amidoamines. These are commonly used in the hardware store variety two-part epoxy resins that cure at room temperature. Both are reaction products of aliphatic amines, such as diethylenetriamine, and should be included under the subclassification of modified amines. However, these products have such widespread and popular use, they are addressed here as a separate classification. 

The Versamid series of curing agents were the original and best known polyamide curing agents. Current commercial polyamide curing agents and their properties are shown in App. D. More recently developed polyamides provide lower viscosity, better compatibility with epoxy resins, and better cure profiles under adverse conditions. 

Amidoamine or polyamidoamine curing agents have reactivity with DGEBA epoxy resins that is similar to the polyamides. However, they are lower-viscosity products and are also lower in color. Amidoamines are derivatives of monobasic fatty carboxylic acids and aliphatic polyamines. Since the amidoamines have only one amide group per molecule, they are lower in molecular weight, viscosity, and amine functionality than the polyamides. 

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