Curing agents, epoxy amidoamines

Conacure AH-35 Conacure AH-66 curing agent, epoxies Amidoamine Aminoethylpiperazine ... 

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. 

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. 

As a family of curing agents for epoxy resins, the amidoamines are lower in viscosity than the polyamides. They exhibit very good adhesive properties due to their chemical structure and easy penetration. Amidoamine cured epoxy adhesives have shown very good properties on concrete and other porous substrates. They cure extremely well under humid conditions. In fact amidoamine cured epoxy formulations have been used to cure underwater in certain applications. A typical general-purpose room temperature curing epoxy-amidoamine system is described in Table 11.7. This adhesive is used as a general-purpose metal-to-metal adhesive and body solder in the automotive industry. 

Whereas most room temperature curing epoxy adhesives are cured with aliphatic amines, polyamides, or amidoamines, most elevated-temperature curing epoxy adhesives are cured with aromatic amines, modified aliphatic amines, alcoholic and phenolic hydroxyls, acid anhydrides, Lewis acids, and a host of other curatives. Latent curing agents, such as dicyan-diamide and imidazoles, are typically used in one-component epoxy adhesives systems. 

Table 14.4 presents formulation information for bisphenol A and polyfunctional epoxy resin emulsions that are cured with an aliphatic amidoamine curing agent. Adhesive performance data are also provided for substrates common to the automotive industry. Both formulas are based on a 1 1 epoxy-amine stoichiometry and they are reduced to 45 percent nonvolatiles with water. The working life of each system is several hours at room temperature. 

General-purpose epoxy adhesive with amidoamine curing agents Effect of fillers on tensile shear strength of polyamide cured epoxy... 

VeX 11-548. [Henkel] Water-reducible amidoamine resin epoxy curing agent... 

Houston, TX), EPON Resin 828 is an epoxy oligomer made from bisphenol A and epichlorohydrin, while EPIKURE 3046 curing agent is an amidoamine mixture [1],... 

Chem. Descrip. Modified cycloaliphatic amine epoxy Uses Epoxy curing agent for high solids coatings accelerator for polyamide and amidoamine curing agents Features Good chem. resist, and low temp, cure (30-35 E) exc. blush resist. 

Uses Antioxidant stabilizer catalyst intermediate R.T. epoxy curing agent activator for epoxy resins cured with wide variety of hardener types incl. polyamide, amidoamines, polymercaptans, and anhydrides for coatings, adhesives, castings, potting, encapsulation Manuf./Distrib. ChemService http //www.chemservice.com, Sigma Trade Name Synonyms Ancamine 1110 [Air Prods./Perf. Chems. http //WWW. airproducts. com]... 

The amine-reactive nitrile liquids are useful in formulating a modified hardener package through admixture with an amine, amidoamine or fatty poly-amide curing agent of choice (14). And novel elastomer-modified epoxy resin hardeners giving excellent reported adhesive properties have begun to appear in the marketplace (15). 

L6WiS BaS6S. Lewis bases contain an unshared pair of electrons in an outer orbital and seek reaction with areas of low electron density. They can function as nucleophilic catalytic curing agents for epoxy homopolymerization as cocuring agents for primary amines, polyamides, and amidoamines and as catalysts for anhydrides. Tertiary amines and imidazoles are the most commonly used nucleophilic catalysts. Several different mechanisms are possible ... 

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