Effect of flow velocity, atmosphere and sample thickness on the mass loss rate of PMMA in the tube furnace

The experiments in this contribution have been conducted in an adapted tube furnace, a new gram scale experiment, based on the ISO 19700, in which an online mass loss measurement has been installed. The benefit of this set-up is that it allows to conduct gramscale pyrolysis experiments under well-defined boundary conditions. In this set-up, samples with a length up to 50 cm can be investigated under different atmospheres and flow rates. In this contribution, the effect of several experiment parameters on the mass loss rate is studied. For this purpose, black cast PMMA samples were heated at a constant heating rate of 5 K/min. The atmosphere as well as the flow rate through the tube furnace were varied. Additionally, samples with different thicknesses were tested. It was observed that unless the sample autoignites, different flow rates do not result in differences in the mass loss rate. Nitrogen versus air atmosphere does make a significant difference on the mass loss rate. Under air atmosphere the PMMA reacts at lower temperature than under nitrogen atmosphere. The thicker the sample, the more the peak mass loss rate shifts to higher temperature and the lower the normalised peak mass loss rate.