Friction and
scratch resistance of polymer liquid crystals: Effects of magnetic field
orientation
Witold
Brostow and Magdalena Jaklewicz J. Mater. Res. 2004, 19, 1038.
Abstract
We have studied
PET/0.6 PHB, an alternating copolymer in which PET is poly(ethylene
terephthalate) and PHB is p-hydroxybenzoic acid with the mole fraction of 0.6
PHB. It is a longitudinal polymer liquid crystal (PLC) with the LC sequences in
the main chain and oriented along the chain backbone. Material not subjected to
the magnetic field, specimens oriented along and perpendicularly to the flux of
the magnetic field, were investigated. Static friction, dynamic friction,
scratch penetration depth, and healing of the material were determined. Static
and dynamic friction parameters for oriented samples have significant higher
values. The best scratch resistance is found for the sample aligned along the
magnetic field. The results are explained in terms of morphology revealed by
scanning electron microscopy and phase structures.