CHARACTERIZATION OF OLIGOMERS IN POLY(ETHYLENE-TEREPHTHALATE) BY MATRIX-ASSISTED LASER-DESORPTION IONIZATION MASS-SPECTROMETRY

Matrix-assisted laser desorption/ionization mass spectrometry was used for the characterization of extracted and synthesized oligo(ethylene terephthalate)s. Generally, cyclic oligomers [GT](n) could be found in technical yarns and tiles, whereas our synthesized model oligomers mainly consisted of linear chains H-[GT](n)-G. In addition, some other distributions could be identified as H-[GT](n)-OH and H-[GGT](1)-[GT](n-1)-G linear oligomers and H-[GGT](1)-[GT](n-1) cyclic oligomers, where G is an ethylene glycol unit, GG is a diethylene glycol unit, caused by impurities of ethylene glycol, and T is a terephthalic acid unit. NMR and IR investigations were carried out to verify these results.