Abstract

CUELLAR BURGOS, Alneira; MESA RUEDA, Fabio Augusto; VARGAS HERNANDEZ, Carlos  and  PERILLA PERILLA, Jairo Ernesto. Characterization of polyurethane-urea/ montmorillonite nanocomposites using XRD and µ -Raman. Rev.fac.ing.univ. Antioquia [online]. 2010, n.54, pp.57-64. ISSN 0120-6230.

In this paper, we used a copolymer ofpolyurethane urea (PUU) and modified montmorillonite (MMT) to obtain its corresponding nanocomposite. The modified silicate was exfoliated in the PUU matrix using an intercalation technique for solution and subsequently characterized by X-ray diffraction (XRD) and µ-Raman spectroscopy. With micro-Raman spectroscopy characteristic modes of both the modified clay and the PUU were identified. The most important ones in the modified clay were two intense peaks located at 2.850 and 2.884cm^-1 for the vibrational mode of -CH- group. The 800-600 cm^-1 vibrational modes corresponding to Si- O-Si connected to the SiO4 tetrahedron and it is the vibrational mode of control of clay located around 707cm^-1. PUU modes could be identified and associated with the bands at 1.640 and 1.716 cm^-1 carbonyl group of urea and urethane respectively. The nanocomposite changes were observed in the intensity of the vibrational modes of the ether group symmetric and asymmetric (912 cm^-1 and 1.200 cm^-1), by incorporation of clay in these phases. By XRD it was determined that the modified clay presented an exfoliation morphology within an amorphous

Keywords : Raman; polyurethane-urea; clay; montmorillonite; nanocomposite.