Classification of OPP adhesive tapes according to MALDI mass spectra of adhesives

Classification of acrylic and rubber-based pressure sensitive adhesives (PSAs) of colorless and transparent oriented polypropylene adhesive tapes distributed in Japan according to matrix-assisted laser desorption/ionization (MALDI) mass spectrum has been studied. MALDI mass spectra of acrylate oligomers and emulsifiers were observed from tetrahydrofuran extracts of acrylic PSAs, and aliphatic petroleum resin, aliphatic–aromatic copolymer and unknown additives were from 2-butanone extracts of rubber-based PSAs. Acrylic PSAs were classified into 10 groups and rubber-based PSAs were into 8 groups. The criteria for the classification according to the MALDI mass spectrum were clearer than according to FT-IR spectrum.