Alkali metal cation adduct effect on polybutylene adipate oligomers: Ion mobility-mass spectrometry

POLYMER

卷:173

Article

Crescentini, Tiffany M.^1,2,3,4  May, Jody C.^1,2,3,4  McLean, John A.^1,2,3,4  Hercules, David M.¹ 

[1] Vanderbilt Univ, Dept Chem, Box 1583, Nashville, TN 37235 USA

[2] Vanderbilt Univ, Ctr Innovat Technol, Nashville, TN 37235 USA

[3] Vanderbilt Univ, Inst Chem Biol, Nashville, TN 37235 USA

[4] Vanderbilt Univ, Inst Integrated Biosyst Res & Educ, Nashville, TN 37235 USA

关键词: Polybutylene adipate;    Alkali cations;    Degree of polymerization;    Ion mobility-mass spectrometry;   

DOI  :  10.1016/j.polymer.2019.04.004

来源: Elsevier

【 摘 要 】

Polyurethane (PU) di-block copolymers are one of the most versatile polymeric materials, comprised of hard and soft segments that contribute to PU's broad range of applications. Polybutylene adipate (PBA) is a commonly used soft segment in PU systems. Characterizing the structure of PBA polymers is essential to understanding complex heterogeneity within a PU sample. In this study, ion mobility-mass spectrometry (IM-MS) and tandem mass spectrometry (MS/MS) are used to structurally characterize a PBA standard (M-n = 2250) adducted with a combination of monovalent alkali cations (Li, Na, K, Rb, and Cs). IM-MS profiles show unique trends associated with each cation-adducted PBA sample. Charge state trends: + 1, + 2, and +3 were extracted for cation-adducted PBA oligomers, and investigated to study gas-phase transitional folding. To quantitatively assess the gasphase structural similarities and differences, a statistical test (ANOVA) was used to compare PBA oligomercation collisional cross sections (CCS). Fragmentation studies (MS/MS) identified the unique behavior of Li and Na for promoting 1,5 H-shift and 1,3 H-shift fragmentation, whereas the PBA precursor preferentially loses the larger K, Rb, and Cs cations as the ion activation energy is increased. The combination of adducted alkali cations, IM-MS, and MS/MS allow for unique structural characterization of this important PBA system.

【 授权许可】

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