Characterization of oligomers in poly(ethylene terephthalate) by matrix‐assisted laser desorption/ionization mass spectrometry

Abstract

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-[GH]n-OH and H-[GGT]1-[GT]n-7/-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.

Reasons for the Discoloration of Postconsumer Poly(ethylene terephthalate) during Reprocessing

“…These findings are in wide agreement with those of Weidner et al for technical poly(ethylene therephthalate) materials . The only exemption here is the lack in cyclic [GGT] 1 ‐[GT] n oligomers, which were detected in small amounts by Weidner and assigned to stem from diethylene glycol impurities in the production process …”

“…Processing of the MALDI‐ToF‐MS data via Polymerix™ Software revealed a total of four molecular weight distribution series, each with the ethylene terephthalate repeating unit of 192.04 Da; traces of PA MXD 6 ions were also detected. For brief denomination of the ethylene terephthalate oligomers, the nomenclature of Weidner et al was adopted with slight modifications . Cyclic and linear PET oligomer series were identified: S1 = [GT] n, S2 = H‐[GT] n – OH, S3 = H‐[GT] n – GH, S4 = H‐[GGT]1‐ [GT] n ‐1‐ GH.…”

Monoisotopic65Cu+ attachment to polystyrene

“…For synthetic polymers, especially for polymers of narrow polydispersity, information can be obtained on the molecular mass distributions with considerable precision and speed; 1-4 structural information can be obtained from the MALDI-TOF mass spectrum from an assessment of the monomer and especially of the end group masses. [5][6][7][8][9][10][11] For homopolymers, the oligomers are separated by the monomer mass. For example, for a polystyrene the isotopic clusters of each oligomer are separated by nominal mass 104 Da and the mass spectra of such polymers are correspondingly relatively simple.…”

Analysis of Polymeric UV Absorber (Tinuvin 213) Using LDI-TOFMS: Solvent Effect in Sample Preparation

“…And the absence of substantial fragmentation and the high sensitivity, combined with the theoretically unlimited mass range, make MALDI time-of-flight mass spectrometry (MALDI-TOFMS) a powerful tool for polymer characterization. [21][22][23][24][25][26][27][28][29][30] It can be used to determine average molecular weights and molecular weight distributions of narrow polydispersity polymers. 31 However, the success of this technique for polymer analysis is dependent on the sample preparation.…”