Preparação e caracterização de membranas microporosas obtidas de nanocompósitos de poliamida 6.

Abstract

Microporous membranes of polyamide 6 nanocomposites with regional clays were obtained by inversion phase method and its microstructure and morphology were studied. The bentonite clay used was organically modified in aqueous environment and characterized by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The results showed the increase in the planar basal distance and the presence of carbonic chain in the clay. The nanocomposites were produced by melt intercalation. It was used a modified clay (ACT) and without modification (AST) with nominal content of 3 and 5wt. The obtained morphological structure was predominately exfoliated, as observed by XRD and transmission electron microscopy (TEM). The XRD and FTIR results also allowed determining the formation of y crystalline phase in the nanocomposite. The membranes obtained by immersion precipitation technique from nanocomposites were characterized by XRD, FTIR, scanning electron microscopy (SEM), TEM and mercury intrusion porosimetry. From the results of XRD and FTIR it was observed the predominance of a crystalline phase formation for almost of the compositions. From porosimetry and SEM images it was observed a change in the morphology of the membranes. These membranes present higher number of pores and small pore size for the nanocomposites when compared with the membranes of neat PA6. The TEM images of the membranes indicated a structure with predominance of exfoliation. The results from SEM suggested an increasing in pore density with higher content of clay and with the presence of organophilic clay.