Re: Ammonium vs potassium dichromate -- Bolte

From: Katharine Thayer <kthayer@pacifier.com>
Subject: Ammonium vs potassium dichromate -- Bolte
Date: Sat, 01 Apr 2006 09:15:32 -0800

> "The structural modification of the polymer matrix in ADC (ammonium
> dichromate) was monitored... The ammonium cations observed before
> irradiation were very rapidly consumed during the first step of the
> (chromium) reduction. The most probable reaction could be the one
> involving them and ester groups leading to amide functions -CO-NH2.
> Accordingly, we looked at the eventual formation of amide groups
> characterized by two vibration bands which nicely matched the
> experimental observation of bands at 1658 and 1620 cm-1. The
> formation of such bands were only observed with ADC doped PVA. There
> was an additional confirmation of the assumption through the linear
> correlation between the formation of the amide and the consummation
> of NH4-.

Did they perform the same experiment and measurement for ADC or KDC
and polyacrylamide and confirm that the rate of insolubilization is
the same between ADC and KDC? (In polyacrylamide everything is already
amide ester and additional ammonium cation should have no role in the
above mechanism.)
Received on Sat Apr 1 17:43:00 2006