Preparation and characterization of soy lecithin-modified bentonites

DANILA MERINO; ROMINA OLLIER; MATÍAS LANFRANCONI; VERA ALVAREZ

APPLIED CLAY SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 127 p. 17 - 22

0169-1317

In this work, a study of exchange of soy lecithin, a natural product, in bentonite was performed in order to synthesizebio-organoclays. The effects of initial amount of modifier and reaction time were studied at a fixed reactiontemperature. Organoclays thus obtainedwere characterized by means of X-ray diffraction (XRD) analysis, Xrayfluorescence spectrometry (XRF), thermogravimetric analysis (TGA), Fourier transforminfrared spectroscopy(FTIR) and water absorption tests. An effective intercalation of soy lecithin between the clay layerswas obtained.The ionic exchange reaction was completed at short times whereas variations in the initial amount of modifierproduced organoclayswith different final properties. At lowratios of soy lecithin to bentonite, a slight incrementin basal spacing of organoclays was observed due to intercalation of the organic modifier between the clay layersand a significant diminution on water absorption was achieved. When the organic content increased, the interlayerspacing increased but thermal stability of organoclays decreased compared to the sampleswith loworganiccontent, whereas the water absorption was not affected. The obtained bio-organoclays are potentialenvironmental-friendly fillers for the development of clay/biopolymer nanocomposites.