Molding Process
4 visualizaciones
PVC De-HCl Degradation Mechanism
Fenómeno del problema
Products turn from yellow to brown then black, accompanied by pungent odor; once degradation occurs it spreads rapidly
Análisis de la causa
C-Cl bond in PVC molecule is weak, dehydrochlorination zipper-style when heated: once one chlorine is removed, an allyl chloride site forms which is more unstable, chain removal of HCl; released HCl autocatalytically accelerates degradation
Solución
①Once degradation occurs, immediately stop and replace barrel; ②Heat stabilizer formula is the first line of defense against degradation; ③Dual control of temperature and residence time; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Conclusión clave
PVC degradation is an autocatalytic chain reaction; once started it is irreversible and spreads with acceleration, prevention is the only effective strategy; after confirming effectiveness, fix the parameters and practices into the work instruction to prevent recurrence
¿Le ha resultado útil?
0 personas encontraron esto útil
¡Gracias por sus comentarios!