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- Author or Editor: M. Košik x
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TG, DTG and simultaneous DTA were used to monitor the thermal decomposition processes of cellulose in nitrogen or in an oxidative atmosphere. Volatile products and solid residues formed during decomposition were analyzed to obtain additional information for elucidation of the thermal curves. An indication of possible flaming or smoldering combustion is discussed. The maximum weight-loss rate, the percentage amount of the residue at the final temperature, and the exothermic peak areas (DTA) could be considered as suitable criteria for the flammability of cellulosics and the activity of flame retardants. The formal kinetic parameters evaluated from the thermogravimetric measurements correspond to the limiting oxigen index (LOI) values. New observations were made using a combination of thermal analysis and LOI techniques. LOI — smoldering or LOI — flaming are mathematically determined from the plot of weight-loss rate versus oxygen concentration.
TG, DTA, pyrolytic GC and mass spectrometry methods were used to study the effect of (bis(2-chloroethyl)l-bromovinyl phosphonate on the thermal- and thermooxidative destruction of acetylcellulose. On heating the BVP-containing AC in air the initiation and intensive decomposition of the polymer was found to occur at a reduced temperature. In an inert atmosphere one can also observe a decrease in the characteristic AC decomposition with increasing BVP. The modification results in an accelerated process of dehydration and deacetylation. The effective energy of deacetylation activation (between 220 and 270 °C) decreases from 135 to 80 kJ/mol on the addition of 5.0 wt.% BVP. A comparative study of the mass spectra of the modified AC subjected to stepwise heating up to 300 °C at a rate of 10 deg/min was carried out.
