RESUMO
Solid state transformation of crude poly (ethylene terephthalate)(PET) and PET/nano-CaCO3 (MPET) composites were studied by variable temperature FTIR spectroscopy during the heating process from 40 to 250 degrees C. The effects of nanometer calcium carbonate(nano-CaCO3) on the solid state transformation and crystal correlation bands of MPET composites were analyzed by the curves of the ratio of 1 342 and 1 410 cm(-1) absorbency(A1 342/A1 410) with temperature increasing, and together with DSC curves in the same condition. The results showed that the crystallization degrees of crude PET and MPET are obviously different in this condition by adding nano-CaCO3 particles as inhomogeneous nucleating agents.
RESUMO
Variable temperature FTIR spectra method was used to study the crystalline spectra of crystal compounds. In the present paper, the sample of L-LA was synthesized and characterized by FTIR, NMR and DSC. It was found that the two peaks in therange of 800-770 cm(-1) changed sharply at 95 degrees C after being investigated by FTIR spectra between 15-120 degrees C. When the temperature increased, these peaks remained almost unchanged, but they returned to the original state after annealing. It was deduced that these two peaks are linked to the crystalline of L-LA.
