Thermal degradation of reactive polyurethane hot melt adhesive based on MDI

The reactive polyurethane hot melt adhesive (HMPUR) was synthesized via bulk polymerization of poly(butyleneglycol adipate) (PBA), poly(ethylene orthophthalate) (PEO), poly(tetrahydrofurandiol) (PTMEG), 4,4′-methylene diphenyl diisocyanate (MDI) and pentaerythritol diacrylate (PEDA). Its thermal degradation was studied by thermogravimetry (TG) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). In helium atmosphere, the sample was pyrolyzed at three characteristic temperatures of 280, 450 and 600 °C according to the results of TG analysis. More than 20 characteristic volatile pyrolytic products were identified by on-line MS. The pyrolysis reaction types of HMPUR were proposed and verified through the analysis of pyrolytic products.