Impact of Exfoliated Silicate on the Dielectric Relaxations of Nylon 11 Nanocomposites in the Melt and Solid States

Published

August 1, 2004

Author(s)

T Y. Lee, Anthony J. Bur, S C. Roth, P R. Start

Abstract

Melt state properties of nylon 11 and its exfoliated silicate nanocomposite were monitored during extrusion compounding using an online dielectric slit die sensor, and solid-state properties were probed off-line by a dielectric relaxation spectrometer. A comprehensive relaxation master map for nylon 11 and its exfoliated clay nanocomposite featuring six relaxation modes in both melt and semicrystalline states revealed changes in molecular dynamics upon the addition of nanofillers. a relaxation was observed in the neat resin as well as the composite, and a Maxwell-Wagner (MW) relaxation was detected in the composite melt yet absent from the neat molten nylon. The MW relaxation mode, featuring a broader relaxation time distribution and a much greater dielectric intensity compared to the a relaxation, resulted from polarization at the filler/polymer interfaces and can be used to distinguish the neat polymer from the composite during real-time processing.The presence of exfoliated clay particles accelerated the a relaxation dynamics in the solid state as delaminated silicate platelets diminished the intermolecular cooperativity of the amorphous chains. Randomization of molecular dipoles upon increasing temperature was only observed in the neat nylon. Hindered molecular dipole orientation due to the rigid silicate fillers in composite was observed.

Citation

Plasma Processes and Polymers

Volume

228

Pub Type

Journals

Keywords

clay, dielectric, exfoliated, interfaces, intermolecular cooperativity, Maxwell-Wagner interfacial polarization, nanocomposites, polyamides

Citation

Lee, T. , Bur, A. , Roth, S. and Start, P. (2004), Impact of Exfoliated Silicate on the Dielectric Relaxations of Nylon 11 Nanocomposites in the Melt and Solid States, Plasma Processes and Polymers (Accessed April 23, 2024)