Polypropylene/clay nanocomposites: An innovative one-pot process

Abstract

This work discloses a novel one-pot preparation method of polypropylene (PP)/clay nanocomposites with high degree of clay delamination and improved thermal, mechanical and rheological properties. The in situ simultaneous synthesis of carboxylate clay from native clay and ionomer of PP-graft maleic anhydride (PP-g-MA) through trihydrate sodium acetate addition, combined with water injection in the extrusion process, appears to be a valuable alternative to the use of organoclay for producing PP/PP-g-MA/clay nanocomposites. The influence of PP-g-MA graft content, and of its ionomer form, onto the clay dispersion has been especially investigated. PP-g-MA of low graft content is compared to a home-made highly grafted PP-g-MA synthesized in the presence of N-bromosuccinimide (NBS). The nanocomposites prepared by combining the use of NBS-mediated PP-g-MA, trihydrate sodium acetate and water injection exhibit the highest clay dispersion. Thermal, rheological, and mechanical properties of the nanocomposites have been measured. POLYM. COMPOS., 36:644-650, 2015.

Water Transport Properties of Poly(butylene succinate) and Poly[(butylene succinate)-co-(butylene adipate)] Nanocomposite Films: Influence of the Water-Assisted Extrusion Process

“…Taking advantage of the preparation of nanocomposite films, 5 wt % of inorganic clays (native and organo-modified montmorillonites) has been loaded in PBS and PBSA matrices using a recent process, called water-assisted extrusion process, based on the injection of liquid water under high conditions of temperature and pressure in the high compression zone of the extruder barrel during process. This original process is applied because it is reported to be active in increasing dispersion and exfoliation levels of nanofillers into the polymer matrices, as already demonstrated with PP, , PA6, and SAN matrices.…”

Influence of Processing Conditions on the Preparation of Clay-Based Nanocomposites by Twin-Screw Extrusion

“…Same quality of exfoliation was obtained with Na-MMT and water injection as with OMMT without water. Since these preliminary works, water-assisted extrusion has largely developed, essentially to prepare PP-and PA-based nanocomposites with Na-MMT (Yu et al, 2005;Mainil et al, 2010;Molajavadi and Garmabi, 2011;Rousseaux et al, 2011Rousseaux et al, , 2015Touchaleaume et al, 2011a;Stoclet et al, 2013;Stoeffler et al, 2013). Beside the improvement of the exfoliation, it has been shown that the presence of water prevents the degradation of PA6 by a cryoscopic effect (decrease of the melting temperature, allowing to reduce the extrusion temperature) (Touchaleaume et al, 2011b).…”

The effect of montmorillonite modification and the use of coupling agent on mechanical properties of polypropylene–clay nanocomposites

“…22 In the literature, there are articles that report the mechanical, thermal, and morphological characteristics of nanocomposites based on PP, maleic anhydride-grafted PP and MMT. [23][24][25][26][27][28] However, it is difficult to compare the reported results between them because in each study, maleic anhydride-grafted PP with different maleic acid content and molecular weight was used or different organically modified MMT was used.…”