ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Citric acid (CA)-diethylenetriamine (DETA) salts (CADETA) were prepared by using a 4.5 : 1 molar ratio of DETA-CA and removing the DETA excess. The structure of CADETA was analyzed by 13C-NMR, IR, and DSC associated with weight loss. One-step formulations consisted on dispersions of CADETA (variable amounts) in an epoxy resin based on diglycidylether of bisphenol A (DGEBA, EEW = 185.5 g/eq). The cure was followed in the pressure cell of a DSC (N2 at 2.5 MPa), to avoid volatilization of DETA in the temperature range where decomposition of CADETA and beginning of reaction took place (T 〉 175°C). A very small heat of reaction was observed, (-ΔH) ∼ 10 kJ/eq, resulting from the simultaneous endothermic salt decomposition and exothermic network formation. A stoichiometric formulation showed a Tg = 180°C, i.e., some 60°C higher than the one observed for the usual DGEBA/DETA system.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1992.070450407
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