- Author
-
Ziv-Bar, E.
- Title
- Degradation of Polymers at High Temperatures Studied by Single Micron-Sized Particle. BFRL Fire Research Seminar. VHS Video.
- Coporate
- Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Report
-
Video
June 23, 1998
- Keywords
-
high temperature
|
degradation
- Abstract
- A new method for the investigation of the degradation of charring and non-charring polymers has been developed. In this method the degradation is studied in an electrodynamic chamber where a single micron-sized polymer particle is levitated at a fixed position until reaction completion. The particle is heated by a focused laser beam to reach the desired temperature, the particle's surroundings can be controlled and gas flows can be imposed on the particle. The high heating rate (104-105 K/s) and small size of the particle (50-200mm) prevent mass and heat transfer limitations, inevitable in other methods. The method enables one to measure various forces significant for a small particle, such as free-, forced-convection and photophoretic forces, which are sensitive to the temperature, the thermal and optical properties of the particle and the surrounding gas. Valuable information on these properties can be gained on line with the rate of mass loss measurements. The method has been used for investigation of the degradation of polystyrene particles, both in oxidizing and non-oxidizing environments. The character of degradation depends on temperature.