A novel derivative of aromatic polyethersulfone (PES) was obtained by bromination. Victrex PES was reacted with bromine under various conditions: in solution, in suspension, and without solvent; with or without catalyst; and at low and elevated temperatures. Practically no bromination occurred in solution; in the other cases, brominated PESs to various extents were obtained. The degree of substitution (DS) varied between 0.3 and 2.3. It was found that no catalyst is required for this reaction; the temperature, the concentrations of bromine and of polymer in the reaction mixture, and the duration of the reaction are the determinant factors of the DS. The modified polymers were characterized by elemental analysis, 1 H-NMR, 13 C-NMR, and PGC-MS, and their thermal properties were investigated by TGA and DSC methods. Further transformations of brominated PES as well as other new chemical reactions of PES will be the subject of later publications.
Besides the monomer some minor but characteristic volatile thermal decomposition products are observed pyrolysing polyamide‐6 in the presence of PVC. It was proven that hydrogen chloride thermally eliminated from PVC gives rise to facilitated depolymerization of PA‐6, partial hydrolysis of the amide groups, evolution of 6‐chlorohexanenitrile, and promoted nitrile and vinyl end group formation. A mechanism is proposed for the advance of these reactions by hydrogen chloride. Depolymerization and hydrolysis are initiated at a considerably lower temperature in the presence of PVC, at the temperature of the hydrogen chloride elimination from the latter. Studying the aspect of high temperature decomposition it was observed that the presence of PVC severely increased the hydrogen cyanide evolution from PA‐6 at 900°C.
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