Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/5/2004
Publication Date: 4/11/2004
Citation: James, C., Gordon, S.H. 2004. Molecular interaction between polymers estimated by differential spectral deconvolution. National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (NOBCChE). 2004. p. 5.
Technical Abstract: Differential spectral deconvolution (DSD) is a new analytical technique that was devised to uncover evidence of molecular interaction such as hydrogen bonding between polymers in thermoplastic solid blends. The method uses Gaussian/Lorentzian curve fitting to differentiate deconvoluted FTIR spectra of melted polymer blends from deconvoluted FTIR spectra of equivalent mixtures of cryogenically separated polymers. Infrared spectra of polymer blends, where interaction exists, differ from spectra of physical mixtures of the neat polymers. Deconvoluting spectra of the blends into their underlying bands reveal theorectically expected effects of molecular interaction. This technique is superior to conventional spectral subtraction using Beer's law and is applicable to intimate mixtures or solid solutions in general. It was shown earlier that DSD afforded a quantitative estimate of the extent of hydrogen bonding between poly(lactic acid)(PLA) and poly(hydroxyester ether)(PHEE) in two-component blends. The new technique is now applied to three-component thermoplastic blends of PLA, PHEE, and starch. Preliminary DSD results indicate quantitation of the degree of interaction can be achieved even in the presence of strong interaction such as that produced by extended heating and gelatinization of starch in thermoplastic polymer blends.