Authors: M Chehimi S Lascelles P Armes
Publish Date: 2014/04/27
Volume: 41, Issue: 5-6, Pages: 671-677
Abstract
pToluene sulfonatedoped polypyrrole PPyTos powder has been characterized by inverse gas chromatography at various temperatures We have used apolar nalkanes and polar probes of differing acidity and basicity to interrogate the London dispersive and Lewis acidbase properties of PPyTos respectively We have found that the London component of the surface energy γsd is about 90 mJ · m−2 at 25°C and the acidbase contribution to the free energy of adsorption ΔGa AB for Lewis bases is higher than 8 kJ · mol−1 These results show that PPyTos is a high energy material and is capable of very strong specific acidbase interactions Lewis acidity is however dominant and is shown to increase with temperature The determination of the heats of adsorption for tetrahydrofuran and ethyl acetate enabled us to determine Drago’s EA CA EB and CB parameters Whilst EA and CA are similar to those published for chloridedoped polypyrrole and rank PPyTos as a hard acidic species the EB and CB values suggest that PPyTos is a very soft Lewis base
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