Relative Quantification of Dynamic Infrared Linear Dichroism Signals and Their Relation to Thermomechanical Properties

Multivariate curve resolution (MCR) combined with alternating least squares (ALS) has been applied to dynamic infrared linear dichroism (DIRLD) spectra to provide relative quantification and relate this information to the thermo-mechanical properties of a poly(ester urethane). MCR-ALS analysis reduces the DIRLD data matrix to submatrices of factors and scores. The factors represent spectra-like variables that relate to the DIRLD spectra of the major components constituting the individual DIRLD spectra in the data matrix. The scores are related to the concentration of these factors, and serve as a method to semiquantify the components that represent the primary molecular-level mechanisms in the dynamic mechanical temperature scan.