When used as a nanofiller for the preparation of polymer/clay nanocomposites (PCNs), Cloisite 30B (30B) often undergoes a d-spacing collapse, as demonstrated by a shift to wider angles of the XRD basal reflection. Such collapse has been variously attributed to organoclay contamination or, more often, to thermal degradation of the organic modifier with expulsion of the volatile products from the galleries. In this work, several PCNs loaded with 30B have been prepared by melt compounding, using different polymer matrices, and have subsequently been subjected to dissolution in appropriate solvents followed by precipitation in excess non-solvent and room temperature drying. An XRD analysis of the products has shown that this treatment makes the 30B basal plane reflection go back to the original angular position. These experiments indicate that, contrary to the situation prevailing when 30B is subjected to thermal treatments at temperatures well above the onset of degradation (180 °C), the d-spacing collapse observed after melt compounding 30B with polymer matrices at moderate temperatures is in fact a reversible phenomenon probably due to rearrangement of the alkyl chains of the clay modifier in a disposition intermediate between bilayer and monolayer.

On the interlayer spacing collapse of Cloisite 30B organoclay

FILIPPI, SARA;PACI, MASSIMO;POLACCO, GIOVANNI;MAGAGNINI, PIER LUIGI
2011-01-01

Abstract

When used as a nanofiller for the preparation of polymer/clay nanocomposites (PCNs), Cloisite 30B (30B) often undergoes a d-spacing collapse, as demonstrated by a shift to wider angles of the XRD basal reflection. Such collapse has been variously attributed to organoclay contamination or, more often, to thermal degradation of the organic modifier with expulsion of the volatile products from the galleries. In this work, several PCNs loaded with 30B have been prepared by melt compounding, using different polymer matrices, and have subsequently been subjected to dissolution in appropriate solvents followed by precipitation in excess non-solvent and room temperature drying. An XRD analysis of the products has shown that this treatment makes the 30B basal plane reflection go back to the original angular position. These experiments indicate that, contrary to the situation prevailing when 30B is subjected to thermal treatments at temperatures well above the onset of degradation (180 °C), the d-spacing collapse observed after melt compounding 30B with polymer matrices at moderate temperatures is in fact a reversible phenomenon probably due to rearrangement of the alkyl chains of the clay modifier in a disposition intermediate between bilayer and monolayer.
2011
Filippi, Sara; Paci, Massimo; Polacco, Giovanni; N., Tzankova Dintcheva; Magagnini, PIER LUIGI
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/145484
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 39
  • ???jsp.display-item.citation.isi??? 36
social impact