[kasper1115]

For a school project I am trying to electrochemically synthesize polypyrrole. I used a solution of 800 ml 0.5M pyrrole (aq) and 0.5M dodecylbenzensodiumsulfonate(aq). I placed an electrode and an anode made of carbon in the solution and ran a current of 12mA through the solution. the current was falling throughout the experiment for the first 20 minutes. after that it remained stable. I expected the polypyrrole to synthesize as seen in figure 1 of this paper: https://www.ncsu.edu/bioresources/BioRes_06/BioRes_06_3_3585_Sasso_BZCPB_Polypyrrole_Cellulose_Conducting_Mater_Review_1901.pdf

after 30 minutes nothing had synthesized however, and I don't know why. can anybody help me with this?

[Arkcon]

This is a pretty advanced topic for a high school project, but OK, I'll bite.  Assuming you conducted the condensation reaction as described, how did you expect to detect polypyrroles?

[zoork34]

PPy typically forms on an electrode as a black powder-like substance, but if you are trying to use the SDS, I am not sure what color the film will be.  It is possible that you formed a small passivating film on the electrode and that it is not very visible to the naked eye.  What are you using for your electrochemical setup?  12 mA is a lot of current.  I would take a step back and use a different electrolyte such as NaCl or something more simple. 

Also, if all you are trying to do is polymerize the pyrrole, you could do it chemically by just adding some hydrogen peroxide to your pyrrole solution. 

[billnotgatez]

@kasper1115
The paper you cited is 36 pages long.

On what page was the protocol you are using mentioned?


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[Enthalpy]

12mA and 20min make a very small charge for electrochemistry, which doesn't fit 0.4mol of reactant. What amount of product did you expect? Did you evaluate what current and duration are necessary for you goal?

Just as a hint, this charge makes 0.00015 mol electrons.