The Thermal Degradation of Some Polymers Based Upon p-Hydroxybenzoic Acid

Three polymers based upon p‐hydroxybenzoic acid have been studied by thermogravimetry to ascertain their relative thermal stabilities in both inert and oxidising atmospheres. Experiments have been carried out at a rate of temperature rise of 2°C min−1 and isothermally at a number of temperatures. The polymers have good thermal stability. They have also been examined by pyrolysis gas chromatography mass spectrometry using two different procedures. In the first, fresh samples were pyrolysed at a number of increasing temperatures, whereas in the second, the same sample was subjected to successive pyrolyses at the same temperature intervals. The results are compared with those of other authors derived using different techniques.