Portal de Periódicos da CAPES

The effect of radical trapping reagents upon formation of poly(α‐tetrahydrothiophenio para ‐xylylene) polyelectrolytes by the wessling soluble precursor method

1992; Wiley; Volume: 30; Issue: 10 Linguagem: Inglês

10.1002/pola.1992.080301018

1099-0518

Frank R. Denton, Paul M. Lahti, Frank E. Karasz,

Conducting polymers and applications

Abstract Molecular weights were studied by gel permeation chromatography of derivatized poly(α‐tetrahydrothiophenio para ‐xylylene) chloride produced by aqueous or methanolic base‐induced polymerization of 1,4‐bis(tetrahydrothiopheniomethyl) benzene dichloride, both with and without a variety of added polymerization inhibiting agents. Efficient radical scavenging agents such as 2,2,6,6‐tetramethylpiperidinoxyl and hydrogen atom donor 2,4,6‐tri‐ tert ‐butylaniline reduced the degree of polymerization of the reactive α‐(tetrahydrothiophenium chloride)‐ para ‐xylylene intermediate produced in this chemistry, and in some cases completely suppressed formation of high polymer. These two traps did not affect the equilibrium production of the para ‐xylylene by UV‐Vis spectral analysis; hence they must affect the subsequent polymerization chain propagation steps in the mechanism. Electron spin resonance studies of polymerization in the presence of 0.00025 equiv of TEMPO showed disappearance of the spin label, a result consistent with a radical scavenging process. The results suggest that production of high molecular weight poly(α‐tetrahydrothiophenio para ‐xylylene) chloride proceeds through a radical chain propagation sequence. © 1992 John Wiley & Sons, Inc.