Repositori URV

Identifier: TDX:787

Handle: https://hdl.handle.net/20.500.11797/TDX787

Authors:
Garrido, Mariano Enrique

Abstract:
This Thesis, entitled: 'Quantitative monitoring of epoxy resins reactions by near infrared spectroscopy and curve resolution methods' has two main objectives. Firstly, to evaluate the capability of near infrared spectroscopy, assisted by Multivariate Curve Resolution-Alternating Least Squares meted, to quantitative monitor curing reactions of epoxy resins. This objective also involves verifying if the combination of these techniques (both, instrumental and chemometric) is able to detect all the sources of variability present in the system under study. Likewise, this objective involves the quantitative determination of the concentration of the species that take place in the reaction, as well as their corresponding spectral profiles. As a consequence, a study related to the uncertainty of the results and to the appropriate validation strategies must be designed. The second principal objective is to estimate the kinetic rate constants liked to the reactions of epoxy resins. This objective involves the study of the curing mechanism and the relationship between this mechanism and the final properties of the polymerization product.Epoxy resins are among the most important polymer materials in use because of their chemical resistance, notable adhesive characteristics, and good mechanical and physical properties. The final properties of the polymer depend on the chemical structure of the epoxy resin and the curing agent (in this case, the amines), but also on the curing process. Therefore there is a need for new analytical methods that are able to monitor the curing reactions.Near infrared spectroscopy is an attractive tool for monitoring the curing reactions and has certain advantages: is a non-destructive technique and has a wavenumber domain in which the absorption bands are