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The thermal degradation of a series of cured melamine‐formaldehyde resins and of two relevant model compounds has been investigated using thermogravimetry accompanied by the analysis of volatile products. Low temperature degradation reactions which occur up to ∼350°C involve the loss of water and formaldehyde, the latter arising from reversible demethylolation reactions. It is proposed that ether linkages, which model compound studies indicate would yield formaldehyde in the low temperature region, are not present to any significant degree in cured resins. Deep‐seated rupture of the polycondensate system takes place at temperatures above ∼375°C when a number of independent reactions involving both side‐chain and ring degradation give rise to products among which ammonia, hydrogen cyanide, carbon monoxide and melamine have been examined.

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A study of the pyrolysis of Athabasca bitumen has been made using the pyrolysis-gas chromatographic technique. At temperatures below 500 °C the evolution of volatile products from bitumen is dominated by a distillation process. Pyrolysis becomes more important in the higher temperature regions; by 950 °C deep-seated degradation to gases and light ends is dominant. The apparent activation energy of the low-temperature process is reported.