Poly(vinyl chloride)/Kaolinite Nanocomposites: Characterization and Thermal and Optical Properties

Abstract

Nanocomposites of poly(vinyl chloride) (PVC) have been prepared by solution intercalation method using both natural and modified kaolinites. Kaolinite was modified with dimethyl sulfoxide (DMSO) to expand the interlayer basal spacing. The characterization of PVC/kaolinite nanocomposites was made by X-ray diffraction (XRD) and transmission electron microscopy (TEM); the interactions between kaolinite and PVC was discussed by FTIR-ATR; the thermal stability was determined by simultaneous DTA/TG. FTIR-ATR confirms hydrogen bonds formed between dimethyl sulfoxide molecules and the inner surface hydroxyl groups of kaolinite. XRD and TEM results give evidence that kaolinite was dramatically intercalated into nanoscale and homogenously dispersed in the PVC matrix. Thermogravimetric analysis indicated that introduction of clay to the polymer network resulted in an increase in thermal stability. Ultraviolet (UV) absorbance experiments showed that nanocomposites have a higher UV transmission than PVC film. The Kissinger method was used for calculation the decomposition activation energy. The results have shown that activation energy values at both stages for PVC/kaolinite nanocomposite are higher than those of pure PVC, indicating that addition of kaolinite particles improves thermal stability of PVC.

Influence of interlayer functionalization of kaolinite on property profile of copolymer nanocomposites

“…As a result, kaolinite has been described as nonexpandable for a long time, until it was revealed that some polar molecules could be intercalated into the interlayers of kaolinite. This clay mineral is an inexpensive additive that can improve the properties of materials (Bailey, 1988;Pinnavaia and Beall, 2000;Alkan et al, 2005;Turhan et al, 2010) and is widely used in industry as paper or cosmetics additive, and in ceramics. However, interlayers of kaolinite are not easily accessible; its interlayer chemistry is much less developed than Mt.…”

Avaliação da capacidade de adsorção do corante azul de metileno em soluçãoes aquosas em caulinita natural e intercalada com acetato de potássio

“…Na região entre 3600 e 3700 cm -1 é observado duas bandas bem definidas, sendo que a banda em 3688 cm -1 é característica do estiramento do grupo OH. E a banda em 3619 cm -1 está relacionada à hidroxila interna orientada quase paralelamente à direção da camada (001), apontada na direção da vacância do sítio octaédrico e, geralmente, não muito influenciada pelas reações de modificação interlamelar [21]. Os espectros de infravermelho da amostra intercalada (Fig.…”

Modification of Kaolin Mineralogy and Morphology by Heat Treatment and Possibility of Use in Geotechnical Engineering

“…Kaolinite (A12Si2O5(OH)4) is a 1:1 type clay mineral composed of stacked layers of SiO4 tetrahedral (silica) sheets and AlO2(OH)4 octahedral (alumina) sheets. The ideal chemical composition is Al2O3 39.53%, SiO2 46.51% and H2O 13.96% [4]. The particles tend to agglomerate more strongly at a higher temperature and produce higher amount of coarse particles.…”