IDENTIFICATION OF TACKIFYING RESINS AND REINFORCING RESINS IN CURED RUBBER

On-line thermogravimetic analysis/Fourier transform-infrared spcctroscopy (TGA/FT-IR) and pyrolysis-gas chromatography/mass spectrornctry (Py-GC/MS) were employed lo identify the tackifying resins and reinforcing resins in cured rubber. Py-GC/MS gave better results in the identification of the resins than the on- line TGA/FT-IR method. The mass spectra of resins in cured rubber were characterized by comparing the mass spectra of the pyrolyzates of raw resins and those of cured rubber containing the resins. f-Butylphenol acetylene condensed resin, coumarone-indene, Cg-oligomeric Escorez 1102, modified wood rosin, and reinforcing modified cashew resin were studied. The results show that on-line Py-GC/MS is powerful tool in the analysis of the resins in cured rubber. The diagnostic m/z values of the resins for direct analysis in cured rubber were summarized. Reasonable structural information for resins could be acquired by the characteristic fragmentation patterns.