How does food colouring affect a polymer?

[mta02hm]

Hi all,

I have been given two polymer samples and the only difference between the two is one contains food colouring and one does not. My understanding is that the food colouring would colour the sample and that is all!

The sample without food colouring quickly dissolves in THF but the sample with the food colouring does not dissolve! Usually a sample wont dissolve when crosslinking has occured but the food colouring should not have this affect on the structure! Any ideas what is going on?

Thanks in advance for your help!

 

[IRstuff]

Are you sure that food coloring doesn't affect the crosslinking?

Food dyes can be soluble in water:

http://en.wikipedia.org/wiki/Allura_Red_AC'

one would think that this might interfere with the covalent bonds formed in normal crosslinking.

Another possibility is that the crosslinking occurred, but the food dye aids the THF to break bonds somewhere in the structure.

TTFN

FAQ731-376

 

[patprimmer]

Your question is far to broad. There are many hundreds of food colours and thousands of polymers and each can have a large range of additives.

Additives or colours can occasionally act as a catalyst for reactions in some polymers.

Example, Only when dyed with a specific scarlet dye, Sodium perborate solution ate holes in cotton towels only in areas in contact with copper.

Regards

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