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001-es BibID:	BIBFORM010304
Első szerző:	Nagy Lajos (vegyész)
Cím:	Dopant-Assisted Atmospheric Pressure Photoionization Mass Spectrometry of Polyisobutylene Derivatives Initiated by Mono- and Bifunctional Initiators / Lajos Nagy, Viktória Pálfi, Mijid Narmandakh, Ákos Kuki, Andrea Nyíri, Béla Iván, Miklós Zsuga, Sándor Kéki
Dátum:	2009
Megjegyzések:	Nine polyisobutylene (PIB) derivatives with different end groups (chlorine, vinyl, isobutenyl, 2,2-diphenylvinyl, and carboxyl) and molecular weights (1000 to 4500 g/mol), initiated by monofunctional and aromatic bifunctional initiators were studied by atmospheric pressure photoionization mass spectrometry (APPI-MS) in both the negative and the positive ion modes. Consistent with previous findings, negative ion APPI-MS revealed end-group identities through the formation of PIB adducts with chloride ions formed in situ from a chlorinated solvent (e.g., CCl4) in the presence of a dopant (toluene). In positive ion mode, considerable fragmentation of these PIB derivatives was observed, rendering end-group determinations very difficult. The Mn values obtained by APPI(-)-MS were considerably lower than those determined by SEC for PIB derivatives with Mn higher than 2000 g/mol. PIBs containing carboxyl termini can undergo collision-induced dissociation, yielding structurally important product ions. The resulting APPI-MS/MS intensities were found to reflect the "arm-length" distribution for PIBs with bifunctional aromatic moieties. In positive ion mode, [M+COCl]+ adducts were observed for PIBs with an aromatic initiator moiety. The origin of the COCl+ species is also discussed.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban Polyisobutylene APPI-MS mass spectrometry chloride ion attachment
Megjelenés:	Journal of the American Society for Mass Spectrometry. - 20 : 12 (2009), p. 2342-2351. -
További szerzők:	Pálfi Viktória Narmandakh, Mijid Kuki Ákos (1966-) (villamosmérnök) Nyíri Andrea Iván Béla Zsuga Miklós (1944-) (polimer kémikus) Kéki Sándor (1964-) (polimer kémikus)
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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