Classification of OPP adhesive tapes according to pyrogram of adhesives.

Pressure sensitive adhesives (PSAs) of colorless and transparent oriented polypropylene (OPP) adhesive tapes were analyzed by pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS). The PSAs were acrylic and rubber-based PSAs and the tapes were classified according to total ion current (TIC) chromatograms of the PSAs. The main pyrolyzates of the acrylic PSAs were decomposition products of monomers, monomers, dimmers and trimers. Those of the rubber-based PSAs were the monomers of elastomers, and subtle peaks observed were the pyrolyzates of tackifiers and volatile additives in the TIC chromatograms. Small differences were observed among the classifications of the acrylic PSAs by Py/GC/MS, attenuated total reflection Fourier transform infrared (ATR FT-IR) and Matrix-assisted laser desorption/ionization mass spectrometry (MALDI/MS). The classification of the rubber-based PSAs by Py/GC/MS and that by ATR FT-IR were the same, and a slight difference was observed between those by Py/GC/MS and MALDI MS.