I am doing electrochemical polymerisation by amperometry , chronoamperometry and cyclic voltametry. Is there any method to find out the rate of polymerization by these methods?
The current (amps) from amperometry is the number of coulombs per second, which is you know the number of electrons being transferred during polymerization can be converted to moles of monomer reacted per second, but this is assuming that all current is faradaic current, that all current is only from your monomer redox chemistry, and that every monomer that undergoes a redox change polymerizes. Those are huge assumptions.
The current (amps) from amperometry is the number of coulombs per second, which is you know the number of electrons being transferred during polymerization can be converted to moles of monomer reacted per second, but this is assuming that all current is faradaic current, that all current is only from your monomer redox chemistry, and that every monomer that undergoes a redox change polymerizes. Those are huge assumptions.
Shelley is right, but Shelley is always right. Of course if specifically looking at electrode coating, film formation, there may be optical tricks as well. If the process is slow, disappearance of the monomer might be usefully monitored with, for example, liquid chromatography on small aliquots of the solution over time....
coulombs/s is proportional to moles/s... 1834 - Faraday - insanely great
A useful complementary technique if the reaction is not faradaic is the electrochemical quartz crystal microbalance (EQCM). I published a paper a couple of years ago looking at the polymerisation of acrylonitrile, where the propagation reactions are chemical rather than electrochemical: http://dx.doi.org/10.1016/j.electacta.2013.02.084
Of course then you have another bunch of assumptions regarding the nature of the polymer on the crystal, but that's a different story. Conducting polymers are in my experience easier to study with this method than insulating ones.
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