Morphological and adhesive properties of polypyrrole films synthesized by sonoelectrochemical technique

Abstract

This paper presents sonochemically deposited polypyrrole films and their characteristics of adhesion on substrate with related to the surface roughness and morphology by comparing to the conventional films deposited electrochemically. In particular, the use of high frequency sonication (500 kHz) for sonoelectrochemical deposition of polypyrrole was reported for the first time. Chronocoulometry was used to electrosynthesize polypyrrole films on Si substrates of different thicknesses in order to determine the influence of the polymer thickness on its rugosity, its morphology and its adhesion force properties. The effects of high frequency sonication on the electropolymerized thin film's properties were investigated using Scanning Electron Microscopy and mechanical probe scanning showing that sonication led to surfaces having a smaller roughness and a better homogeneity than non sonicated ones. The adhesion force properties of polypyrrole films were also studied by means of force-distance curves obtained by Atomic Force Microscopy. For polymer films obtained in the absence of sonication, the measured adhesion forces decreased when the polymer thickness increased. On 2 the contrary, for polymer films obtained under sonication, the adhesion of the films decreased when the polymer thickness decreased.

Tuning the Surface Properties of Polypyrrole Films for Modulating Bacterial Adhesion

“…For example, in the case of PPy‐ToS, adding 1 × 10 −3 m Fe3+ ions to the electropolymerization solution resulted in sporadic micro‐sized cauliflower shapes on the PPy surface, as compared to PPy‐ToS without Fe3+, which had a smooth surface. Adjusting the synthesis parameters, as proposed here, might provide an easier approach to altering PPy roughness and morphology than previously reported methods such as applying ultrasound during polymerization …”

Adhesion Control for Micro- and Nanomanipulation

“…23,24 The adhesion force reduction was already obtained in liquid and dry medium by surface structuring [24][25][26] or chemical functionalisation. 9,[27][28][29] The last technique allows to switch the force from attractive to repulsive by pH solution modification and improves the micro-object manipulation. 27,30,31 In case of randomly rough surfaces, fractal approach is one of the most usual way to predict wear, adhesion force or interaction forces.…”

Control of adhesion using surface functionalisations for robotic microhandling

“…The intrinsic conductive polymer adsorption was performed by the electropolymerisation on silica or gold. The electropolymerization conditions used in this work to electrosynthesize 3,4-polyethylenedioxythiophene (Pedot), polypyrrole (Ppy), polyaniline (Pani) and poly(pphenylenediamine) (Ppd) have already been detailed by Lupu et al [14], [15] and by Dejeu et al [16], [17]. The measurement was done in dry medium just after the film formation (see Figure 2).…”