Characterization of styrene/methyl methacrylate/n‐butyl acrylate terpolymer with Kendrick mass defect analysis in electrospray ionization‐ion mobility spectrometry‐mass spectrometry

Abstract

Rationale: Synthesis of copolymer is one of the major approaches to establish sophisticated polymers. In copolymer analysis in mass spectrometry (MS), an increase in the number of monomer unit species and/or the polymer molecular weight results in complex mass spectra, and a method is required to solve this problem.Methods: In this study, electrospray ionization-ion mobility spectrometry-mass spectrometry was employed to analyze styrene/methyl methacrylate/n-butyl acrylate (St/MMA/nBA) terpolymers via Kendrick mass defect (KMD) analysis. An expanded Fourier transform-based noise reduction method for the copolymer was developed to improve the decrease in the signal/noise ratio observed in the higher m/z region.Results: Low-mass terpolymers (0.7 kDa) were identified by comparing the observed and theoretical results using a two-dimensional KMD plot. For the 1.5 kDa terpolymer, the signal overlap, of which KMD value was not matched with the theoretical one, was interpreted by the shift from the theoretical value in the KMD plot. For the 3.0 kDa terpolymers, the compositional candidates were determined by the prediction based on the compositional information of low-mass terpolymers previously analyzed. The 4.5 kDa terpolymer was interpreted after the expanded noise filtering. Conclusions:The terpolymers, whose molecular weight was up to 4.5 kDa, were successfully characterized at a molecular level. The dependency of the St/MMA/nBA composition on molecular weight was observed; that is, the nBA content decreased with an increase in the molecular weight.

Analysis of Single Sub-Millimeter Microplastic Particles by Capillary Size Exclusion Chromatography

“…For plastics lacking UV absorbance, refractive index detectors (RID) are commonly used in SEC, though RID sensitivity is relatively poor. Recently, we explored the application of electrospray ionization-MS (ESI-MS) for polymer analyses [10][11][12][13]. Combining capillary SEC with MS promises detailed analysis of MPs.…”

Development of Novel Analytical Methods Based on Liquid Chromatography and Electrophoresis

“…progress in MS, as a highly and sensitive detector, is also required. Current MS often equips a functionality of ion mobility spectrometry (IMS), a type of electrophoretic separation in the gaseous phase, and IMS-MS have been applied to various research field [62][63][64][65][66][67][68][69][70][71]. A combination of HPLC with IMS-MS(/MS) is also significant as a kind of multi-dimensional separation.…”