Flame retardancy of polyamide/clay nanocomposites

doi:10.1017/CBO9780511842412.010

9 - Flame retardancy of polyamide/clay nanocomposites

from Part II - Flame retardancy

Published online by Cambridge University Press: 05 August 2011

Yuan Hu ,

Lei Song and

Qilong Tai

Edited by

Vikas Mittal

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Vikas Mittal: Affiliation:
The Petroleum Institute, Abu Dhabi

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Summary

Introduction

Polymer/clay nanocomposites have received considerable attention during the past decade, both in industry and in academia, because of their attractive improvement of material properties relative to pure polymers and conventional polymer composites. The improvements include mechanical, thermal, flame retardant, and gas barrier performance. It is believed that the improvements are mainly attributable to the nanometric size dispersion of the clay and the specific interfacial interaction between the polymer matrix and clay layers.

The structure and properties of clays

The clays commonly used in polymer nanocomposites belong to the family of 2:1 layered silicates or phyllosilicates. The crystal structure of the clay layers is made up of two tetrahedrally coordinated silicon atoms, which are fused to an edge-shared octahedral sheet of either aluminum or magnesium hydroxide. The layer thickness is about 1 nm and the lateral dimension of the layers may vary from 30 nm to several micrometers or even larger, depending on the particular silicate. There is a van der Waals gap between the layers, usually called a gallery or interlayer. Isomorphic substitution within the crystal structure of the layer (for example, Al3+ replaced by Mg2+ or by Fe2+, or Mg2+ replaced by Li+) generates negative charges that are counterbalanced by alkali and alkaline earth cations situated inside the interlayer.

Type: Chapter
Information: Thermally Stable and Flame Retardant Polymer Nanocomposites , pp. 210 - 236

DOI: https://doi.org/10.1017/CBO9780511842412.010 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2011

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