Collision-induced dissociation studies of poly(vinylidene) fluoride telomers in an electrospray-ion trap mass spectrometer.
Although fluorinated polymers are widely used in different applications, they are rarely investigated by "soft ionization" techniques such as matrix-assisted laser desorption/ionization and electrospray ionization (ESI). We report here, the desorption and fragmentation of poly(vinylidene) fluoride (PVDF) telomers in an ion trap mass spectrometer coupled to an ESI source. Protonated and lithiated telomers under collision-induced dissociation resonant excitation show mainly HF losses. Fragmentation of protonated telomers can be rationalized by a double proton-transfer mechanism and that of lithiated and anionic telomers by an ion-dipole mechanism. Both mechanisms predict the formation of a stable aromatic or a linear conjugated species, respectively. For lithiated telomers, we could determine the degree of polymerization (n) from the product ion abundance in MS2 experiments. The nature of the end group plays a substantial role in orienting the fragmentation of the PVDF ions. It is interesting to note that, in MS2 experiments, Li+ and F- act as catalysts in the fragmentation of PVDF telomers. Fragmentation of the PVDF telomer backbone was not observed under any experimental conditions.
Marie
A
A
Laboratoire de Chimie Structurale Organique et Biologique, CNRS, UMR 7613, Université Pierre et Marie Curie, Paris, France.
Fournier
F
F
Tabet
J C
JC
Améduri
B
B
Walker
J
J