Dr. Dmitri Kopeliovich
Kevlar is the trade name (registered by DuPont Co.) of aramid (poly-para-phenylene terephthalamide) fibers.
Kevlar fibers were originally developed as a replacement of steel in automotive tires.
Distinctive features of Kevlar are high impact resistance and low density.
Kevlar fibers possess the following properties:
The disadvantages of Kevlar are: ability to absorb moisture, difficulties in cutting, low compressive strength.
There are several modifications of Kevlar, developed for various applications:
Kevlar filaments are produced by extrusion of the precursor through a spinnert. Extrusion imparts anisotropy (increased strength in the lengthwise direction) to the filaments.
Kevlar may protect carbon fibers and improve their properties: hybrid fabric (Kevlar + Carbon fibers) combines very high tensile strength with high impact and abrasion resistance.