Electrically conducting composites of colloidal polypyrrole and methylcellulose

Synthesis and characterisation of sterically stabilised polypyrrole particles using a chemically reactive poly(vinyl amine)-based stabiliser

“…Since XPS is highly surface-specific (it has a typical sampling depth of only 2-5 nm), this strongly suggests that the thiophene-modified PVAm %) to that in the thiophene-modified PVAm (~3.6 atom %) suggests approximately 53% surface coverage of the PPy particles by the PVAm stabilizer chains. This is perfectly reasonable given that the stabiliser chains are expected to confer only rather patchy surface coverage under ultrahigh vacuum 5 conditions. It is perhaps worth mentioning that, given the chemical grafting mechanism for stabiliser chains, it is conceivable that at least some of the stabiliser is located within the PPy particles, as well as being present at the particle surface.…”

“…A minimum thiophene content of at least 10 mol % was required to prevent macroscopic precipitation (compare entry 2 with entries 5-10 in Table 1). Moreover, stable 5 colloidal dispersions are only formed at an initial stabiliser concentration of at least 20 w/v % based on pyrrole. Nevertheless, this stabiliser efficiency is comparable to the various statistical copolymer stabilisers reported by Simmons et al [13,14,15], which suggests that the thiophene-functionalised 10 PVAm chains act as a relatively efficient reactive stabiliser.…”

“…In principle, this problem can be alleviated by the preparation of colloidal dispersions of polypyrrole particles via aqueous dispersion polymerisation using chemical oxidants such as FeCl 3 . This has been readily achieved using commercial water-soluble polymers such as 30 methylcellulose [5], poly(N-vinylpyrrolidone) [6], poly(vinyl alcohol) [6][7][8] or poly(ethylene oxide) [9], which are physically adsorbed at the surface of the polypyrrole particles and hence confer colloidal stability via a steric stabilisation mechanism. Such particles are typically around 50 to 300 nm diameter and 35 have a number of potential applications, including synthetic mimics for micrometeorites [10] and intrinsically coloured marker particles for immunodiagnostic assays [11].…”

Review Article: Flow battery systems with solid electroactive materials

“…Second, the voltage efficiency is relatively low; researchers are currently addressing this challenge with new conducting polymers, modified polymer synthesis methods, and optimizing the supporting electrolyte. 209,210,[213][214][215] Potential optimization on the counter electrode by adopting a type I design may also be helpful to decrease the overpotential and to take advantage of the power-energy decoupling feature of RFBs. Oh et al reported an all-organic RFB with polythiophene microparticle suspensions as both anode and cathode showing redox activities through two opposite electrochemical process, nand p-doping.…”

Conducting Polypyrrole Shell as a Promising Covering for Magnetic Nanoparticles

“…The combination of PPy with other inorganic materials in order to prepare composites which combine the properties of both materials is a very promising way to extend the application field of PPy but also of the inorganic materials. In order to improve the poor processability of polypyrrole a lot of methods have been explored in the preparation of soluble or swollen PPy (Masuda et al, 1989;Stanke et al, 1993) and dispersible fine powdered PPy (Bjorklund & Liedberg, 1986;Cawdery et al, 1988;Aldissi & Armes, 1991). To extend the application field of polypyrrole, sterically stabilized PPy colloids were synthesized in aqueous media by chemically polymerizing pyrrole monomers in the presence of a suitable water-soluble polymer, such as methyl cellulose or poly(vinyl alcohol) .…”