Caracterización de los monómeros DGEBA y TMAB, y seguimiento de la reacción de entrecruzamiento por espectroscopia Raman

Abstract

Raman spectroscopy is a widely used technique for chemical and physical analyses of materials, which allows for the study of composition and the structure of the samples. Particularly in recent years, it has been used to identify the normal modes of vibration in the chemical structure and in the functional groups of monomers and polymers. This dispersive technique is employed in the study of the epoxy/amine system, where the normal modes of vibration in the system composed of the epoxy oligomer Diglycidyl ether of bisphenol-A (DGEBA) and trimethylene glycol di-p-aminobenzoate (TMAB) are identified. The principal normal modes of vibration were determined for amine groups of TMAB around 1626, 3333 y 3436 cm-1 and for epoxy rings of DGEBA around 736, 915, 933, 1131, 1249-1252, 1407, 2713, 2760 and 3006 cm-1. The peaks associated with nitrogen-hydrogen symmetric and antisymmetric bonds of the amine (1626 y 1687 cm-1) and the symmetric vibration of the CH2 groups of the epoxy group (3006 cm-1) are indicative of the progress of crosslinking reaction.