Typical Polymer Degradations during Pyrolysis

As shown previously, it is uncommon that the side chain reactions will take place independently from any chain scission. Heating at relatively low temperatures between 100° C to 300° C (known as thermal degradation) may lead in some polymers to side chain reactions with elimination of small molecules (such as H2O, HCI), while the polymer backbone still remains intact. At typical pyrolysis temperatures (500-800° C) both types of reactions occur simultaneously or very rapidly one after the other, as combined reactions. Combined reactions may take place either with a cyclic transition state or with free radical formation. The free radicals formed during polymeric chain scission or during the side chain reactions can interact with any other part of the molecule. 

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