Epoxy esters, amine-modified

Salt-spray data (for nos. 1 and 2 in Table V) indicated that, on zinc-phosphated steel, cathodic ED indeed led to considerably better corrosion resistance. On bare steel, however, both cathodic and anodic coatings failed completely. Further, we prepared a number of different, amine-modified epoxy resin esters containing between 30 and 50 %w of drying fatty acids (e.g. no. 3 in Table V). These could all be deposited cathodically and again attained excellent salt-spray ratings on phosphated steel but performed poorly on bare steel. We concluded that cathodic ED prevents phosphate layer degradation (a well-known phenomenon with anodic ED) and thus leads to superior corrosion resistance on pretreated steel. On bare steel the binders performed too poorly to allow comparison between cathodic and anodic ED. 

Amine-modified epoxy resin ester 90 good fair good 9i 0... 

Bisphenol A diglycidyl ether [1675-54-3] reacts readily with methacrylic acid [71-49-4] in the presence of benzyl dimethyl amine catalyst to produce bisphenol epoxy dimethacrylate resins known commercially as vinyl esters. The resins display beneficial tensile properties that provide enhanced stmctural performance, especially in filament-wound glass-reinforced composites. The resins can be modified extensively to alter properties by extending the diepoxide with bisphenol A, phenol novolak, or carboxyl-terrninated mbbers. 

For compounds of epoxy resins based on epoxy-diane ohgomers and resorcinol diglycidyle esters set with amine curing agents, the dependence of Tad oil the content and type of the modifying additive displays distinct maxima. The adhesion strength is enhanced most when the SKD-KTRA rubber is applied at 20% (see Figs. 3.17 and 3.18). With SKN-KTR as modifier the effect is less. 

Carboxylic nitrile liquid and solid elastomers are used to prepare elastomer-modified epoxy liquid and solid resins when it is desirable to have the modifier in the epoxy portion of the system. This is effected through alkyl-hydroxy esterification reactions. This is covered in the literature for uncatalyzed liquid resins (9), for tert-amine catalyzed systems (10), for tert-phosphine catalyzed systems (11), for low molecular weight solid resins advanced from the liquid state (12) and for liquid and solid resins where an additional rubber vulcanization step is carried out in addition to the alkylhydroxy ester adducting step (13). Such adduct preparations offer formulation stability with a wide range of hardener types amines, anhydrides, catalytic, Lewis acids/bases. 

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