THERMAL-DECOMPOSITION OF TETRAZOLE-CONTAINING POLYMERS .4. POLY-1-VINYL-5-METHYLTETRAZOLE AND POLY-1-VINYL-5-PHENYLTETRAZOLE

The thermal decomposition of poly-1-vinyl-5-methyltetrazole (P-1VMT) a nd poly-1-vinyl-5-phenyltetrazole (P-1VPT) was studied by high resolut ion thermogravimetry (HRTG) differential scanning calorimetry (DSC) an d thermal volatilization analysis (TVA). Solid residues, high boiling products, and gases were collected at different stages of the thermal decomposition and identified by FTIR and/or GC-MS. Both P-1VMT and P-1 VPT show complex multistep decomposition on progressive heating. The t hermal decomposition starts from degradation of tetrazole pendant grou ps. At the beginning, P-1VMT presumably eliminates acetonitrile, where as P-1VPT eliminates nitrogen. On further heating, the partially decom posed polymers melt and an evolution of the pendant groups (5-methylte trazole and 5-phenyltetrazole) is observed. Thermal fragmentation of t he polymeric chain occurs at high temperatures (greater than or equal to 320 degrees C).