Ticona has introduced its GUR® MicroPowder ultra-high molecular
weight polyethylene (UHMW-PE) line for use as performance additives
in paints, coatings, plastics, rubbers, sealants and other materials, as
well as in wicking and filtration applications. These extremely fine
powder products of UHMW-PE, have average particle sizes ranging from
30 to 60 microns.
GUR® MicroPowder grades enhance abrasion and mar resistance,
coefficient of friction (COF), chemical resistance, impact strength and
other mechanical properties. Benefits in specific applications include:
• In paint and coatings: Improved surface texture, wear resistance and
gloss reduction.
• In rubber: Low COF and improved thermal properties, impact strength
and abrasion resistance.
• In plastics: Better slip, abrasion resistance and texture.
• In sealants and polishing compounds: Lower cohesive forces.
• In micro-filters: Low pressure drop with fine porosity and improved
mechanical properties.
GUR® MicroPowder with an average particle size of 30 microns, has a
specially engineered particle morphology which creates a unique light
scattering effect when used as a matting agent in coatings. The
60-micron, GUR® MicroPowder grade has smooth, relatively spherical
shaped particles. Both grades disperse and bond well in many
matrices.
GUR® MicroPowders need no additional micronizing processing before
use as do most thermoplastic additives, which are sold as pellets and
must first be ground and sieved to size. The GUR® powders can be
dispersed with standard mixing equipment, usually at concentrations of
3 to 10 wt.%. They also withstand high-intensity mixing with minimum
particle deformation.
The GUR® powders are similar to fluoropolymer powder additives in
that they reduce COF and improve chemical resistance, but they offer
better surface protection than fluoropolymer, e.g., less surface
abrasion loss and higher scratch resistance. GUR® MicroPowder grades
do not absorb moisture, have a melting temperature of about 135°C,
and an effective thermal range of -265° to 90°C. They also have
extended deformation resistance under low mechanical load, even
above their melting point, which can be important in such applications
as filters for hot liquids and coatings cured at high-temperature.
In addition to the standard GUR® MicroPowder grades, GUR® fines can
be classified to provide specific particle size cuts. Ticona is capable of
tailoring particle shapes and molecular weights from 5 to 10.5 million
g/mol for GUR® MicroPowder.