The thermolysis of a polyarylate based on terephthalic and phenolphthalen at relatively low temperatures

Processes of branching and crosslinking occurring during vacuum thermolysis of a polyarylate based on terephthalic acid and phenolphthalein are described from qualitative and quantitative standpoints. The Stockmayer-Schultz equation was used to determine the degree of branching of the polymer; the crosslinking of the latter was characterized by means of the Flory-Rener and Charlesby-Pinner equations. It was found that the crosslinking of the polymer is subject to a random law.