WARF: P100314US02

Manufacturing Polymer Micropellets


Tim Osswald, Martin Launhardt

The Wisconsin Alumni Research Foundation (WARF) is seeking commercial partners interested in developing a method to produce polymer micropellets from a melt using pressurized airflow.
OVERVIEWPolymer-based micropellets can be formed having diameters smaller than 50 microns. The miniscule particles are vital to a number of processes like laser sintering—used to build rapid prototypes and molds—and manufacturing porous plastics parts. To make quality products, control over the shape, size and distribution of particles is key.

Conventional micropelletization techniques can result in particles of dissimilar size, with irregular shapes and surfaces. Such techniques also are expensive and unsuited to various polymers.
THE INVENTIONA UW–Madison researcher has developed a micropelletizing method and apparatus for controlling the size and shape of polymer particles.

In the process, a thin melt of polymer material is extruded through a specialized nozzle. A jet of heated, pressurized air then is applied. This causes the thread to stretch and break up into individual droplets due to surface tension effects known as Rayleigh disturbances.

The droplets are allowed to cool and solidify into micropellets. Factors like temperature, speed and extrusion rate are used to control droplet formation.
  • Plastics processing
  • Laser sintering
  • Polymer-based parts and medical devices
  • Process control
  • Micropellets can be any suitable shape, including spherical.
  • Particle size is adjustable and smaller than two millimeters in diameter. 
  • Suitable to different polymers
For More Information About the Inventors
Contact Information
For current licensing status, please contact Emily Bauer at or 608-960-9842.
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Since its founding in 1925 as the patenting and licensing organization for the University of Wisconsin-Madison, WARF has been working with business and industry to transform university research into products that benefit society. WARF intellectual property managers and licensing staff members are leaders in the field of university-based technology transfer. They are familiar with the intricacies of patenting, have worked with researchers in relevant disciplines, understand industries and markets, and have negotiated innovative licensing strategies to meet the individual needs of business clients.