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>Pyrolysis of untreated and APO‐THPC treated cotton cellulose during one‐second exposure to radiant flux levels of 5–25 cal./cm.2‐sec.
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Pyrolysis of untreated and APO‐THPC treated cotton cellulose during one‐second exposure to radiant flux levels of 5–25 cal./cm.2‐sec.
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机译：Pyrolysis of untreated and APO‐THPC treated cotton cellulose during one‐second exposure to radiant flux levels of 5–25 cal./cm.2‐sec.
AbstractSamples of untreated and APO‐THPC flame‐retardant treated cotton cellulose were pyrolyzed in a helium stream by exposure to flux levels of 5–25 cal./cm.2‐sec. for 1 sec. in a carbon arc imaging furnace. The reaction products were separated naturally into four fractions, which were analyzed separately. Fraction (V−190+V−80) comprised volatile products that failed to condense in cold traps at −80°C. It was swept onto a chromatography column and analyzed immediately. For both fabrics, it consisted of a mixture of CO, CO2, CH4, and ethylene. These light gases accounted for approximately 5 of the total product at 5 cal./cm.2‐sec. and for 18 of the total product at 18–20 cal./cm.2‐sec. FractionVrtwas contained in cold traps, and consisted of products volatile at room temperature, but condensable at −80°C. It was found by gas‐liquid partition chromatography to contain 12 polar organic constituents which were identified with respect to boiling point. The percentage of total product in FractionVrtwas approximately 20 times greater for the treated than for the untreated fabric. The tar fraction,Vpyr, was found condensed at the bottom of the pyrolysis cell, and therefore contained products volatile at the surface of the sample but not at 25°C. It was found in infrared analysis to consist of levoglucosan and an unidentified carbonyl compound. Finally, the weight of residual char was estimated from the weight loss and the area of burn. For both fabrics, the percentage of char decreased with increasing flux level. At every flux level, the average percentage of char was higher for the treated that for the untreated fabric. The mechanism of pyrolysis is similar for both treated and untreated cloth, and for both high and low temperature degradation. A critical step is the formation of levoglucosan by scission of the 1,4‐glycosidic linkages of cellulose. A mechanism for subsequent decomposition of levoglucosan to lower molecular we
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