- Author
- Rhodes, B. T.
- Title
- Burning Rate and Flame Heat Flux for PMMA in the Cone Calorimeter.
- Coporate
- Maryland Univ., College Park
- Sponsor
- National Institute of Standards and Technology, Gaithersburg, MD
- Report
- NIST GCR 95-664; Thesis, December 1994, 125 p.
- Contract
- NIST-GRANT-60NA2D1266
- Keywords
- cone calorimeters | burning rate | heat flux | polymethyl methacrylate | ignition | experiments | mass loss | heating | thermoplastics | small scale fire tests
- Identifiers
- black polymethylmethacrylate (PMMA)
- Abstract
- Ignition and burning rate data are developed for thick (25 mm.) black Polycast PMMA in a Cone Calorimeter heating assembly. The objective is to establish a testing protocol that will lead to the prediction of ignition and burning rate from Cone data. This is done for a thermoplastic like PMMA. For black PMMA, ignition temperatures of 250 to 350 deg C and vaporization temperatures of approximately 325 to 380 deg C were measured over irradiance levels of 15 to 65 kW/m(2). The incident flame heat flux, for irradiation levels of 0 to 75 kW/m(2), is found to be approximately 37 kW/m(2) for black PMMA. Its constancy is shown due to the geometry of the Cone flame. Also, this flame is shown to be nearly transparent for Cone irradiance (>90%). The heat of gasification of the black PMMA used is found to be approximately 2.8 kJ/g; higher than other values reported for PMMA. This is believed to be due to differences in molecular structure or pigmentation effects and the types of PMMA tested. A burning rate model is demonstrated to yield good accuracy (>80%) in comparison to measured transient values.