PI-CONJUGATED POLY(MONOSUBSTITUTED) ACETYLENES CONTAINING SN(II) AND SN(IV) SPECIES - INVESTIGATION WITH LASER IONIZATION MASS-SPECTROMETRY

Polyenes [HC=CR](n) (R = Ph, C13H9O), namely polyphenylacetylene (PPA) and polyethynylfluorenol (PEFI) containing Sn(II) and Sn(IV) in the p olymer matrix, have been investigated using laser ionization mass spec trometry. The positive ion mass spectra show that carbon clusters link ed to Sn, i.e. SnCnH+ (n = 1-25) are formed for PPA, while a higher de gree of fragmentation occurs for PEFI which gives SnCnH+ (n = 1-8). Th e species SnCl3- is found in the negative ion patterns of the two poly mers, regardless of whether the dopant was SnCl2 or SnCl4. This result suggests a lower stability of the tin complexes, formed by interactio n with the polymer matrix, with respect to the iron chlorides or polyi odides species found in the LMS spectra of PPA/FeCl3 and PPA/I-2, resp ectively, previously studied. (C) 1998 Elsevier Science B.V.