Authors: D.R. Paul
Affilation: University of Texas at Austin, United States
Pages: 503 - 506
Keywords: organoclay, polyolefins, ionomers
Polymer-layered silicate nanocomposites formed from the organically modified clay mineral montmorillonite and related materials have attracted a great deal of technological and scientific interest in the past decade. These composites offer the promise of greatly improved properties over those of the matrix polymer owing to the nanoscale reinforcement and constraints of the polymer caused by dispersing the one nanometer thick, high aspect ratio aluminosilicate layers. However, the key to achieving these benefits is dispersing the organoclay into the polymer matrix to generate high aspect ratio particles. The preferred route to making such nanocomposites is to use melt-processing techniques. This presentation will give a status report on what is known about generating and characterizing the structure of such nanocomposites and the relationship of this structure to various properties. Many factors are involved in achieving a high level of dispersion, or ultimately full exfoliation, but one of the most important is the complex interaction of the polymer matrix with the organoclay. This is illustrated by the extremes of highly polar polymers like polyamides where exfoliation can be very high to highly non-polar polymers like polyolefins where exfoliation is generally rather poor. Of course, polyolefins provide the greatest market opportunities. This talk explores some opportunities for creating useful nanocomposites by using polyolefins containing polar functional groups, including ionic groups, that improve the interaction with the organoclay and subsequently exfoliation and performance.