Pyrolysis mass spectrometric analysis of poly(pyrrole-g-(2-(N-pyrrolyl)ethylvinylether)

摘要

Preparation of block and graft copolymers of conducting polymers with insulating polymers with good mechanical properties have been attempted in order to improve their mechanical properties. Yet, complete structural characterization is still limited due to the insolubility of the polymer samples. In this work, direct insertion pyrolysis mass spectrometry technique had been applied for structural and thermal characterization of a polymer prepared by electrochemical polymerization of pyrrole on a poly(2-(N-pyrrolyl)ethylvinylether) (PPEVE) precoated anode. For this purpose, pyrolysis analyses of polypyrrole (PPY), PPEVE and polypyrrole/poly(2-(N-pyrrolyl)ethylvinylether) graft copolymer (PPY/PPEVE), were performed. The extent of dissociation during the ionization in the mass spectrometer was investigated by repeating the experiments at different electron energies. Single ion current temperature profiles of characteristic fragments evolved during the pyrolysis of each component of the copolymer was compared with those of the corresponding fragments evolved from the copolymer, PPY/PPEVE. Experimental results confirmed that the growth of pyrrole takes place through the pyrrole moieties of PPEVE. The observed increase in the relative intensities of the monomer, and low molecular weight oligomer peaks of pyrrole in the pyrolysis mass spectra of the copolymer, was attributed to a decrease in the extent of network structure, which is common for the electrochemically synthesized PPYs.