Polymer charge state distributions

Field desorption (FD) and fast atom bombardment (FAB) mass spectrometry provides mass spectral information about compotmds that are not very volatile but these two techniques are not used often in polymer science since they have several disadvantages. Electrospray ionization (ESI) mass spectrometry can also be used to obtain the above information about polymers, but ESI spectra are generally complicated due to differences in charge state distributions. Static secondary ion mass spectrometry (static SIMS) is a surface-sensitive MS technique, which is suitable for studying the interfaces of polymers with respect to chemical structure and molecular weight as well as end groups and surface contaminants. Laser desorption... 

MALDI is usually favoured over ESI as a technique for polymer analysis because the spectra obtained from ESI are typically complex because of charge-state complications. However, ion-molecule reactions in quadrupole ion trap have been used as an effective means of reducing the charge-state distribution complexity of spectra generated using ESI [84]. 

Figure 9. Charge state distributions in polymers. A) Poly(chloro-...

Let us briefly discuss a possible alternative scenario, which has been proposed based on the consideration of the unique characteristics of the charged torus and the crucial role of the combinational entropy of the segment state distribution along the chain [41]. The free energy F(N) of a folded polymer with N segments is generally written in the following form ... 

The solution-processed films were annealed at 453 K under UHV for 1 h to further remove the contamination/solvent and improve the crystallinity. By comparing with the NEXAFS that has much deeper probing depth, we can get the clear picture of electronic states distribution from inside to outside. Overlap of n-electronic wavefunction within the lamellae planes should be responsible for the high intralayer mobility in P3HT films. On the other hand, Jt-electronic states distributed outside the polymer surface provide the possibility of forming overlap with the Jt-electronic wavefunction of an overlayer molecular material, consequently achieving efficient charge transfer in the related heterojunction structure used for polymer devices. 

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