Yes - thanks!
   R
   Julia Say wrote:

On 13 Jan 2010, Richard York wrote:



Julia, I love this word "snotomer" but confess I haven't met it before,
neither has Google, it appears... I can sort of guess...
Please explain, with footnotes where appropriate :)


I worked for 10 years in a polymer research unit in the 90s, and the word was
current then.

Polymers are (and this is the very simple version, folks) long chains of carbon
molecules with various different bits hanging off the "sides".
So methane (which has one carbon atom and four hydrogen) is a gas. Propane and
butane, which are straight chains of 3 and 4 carbons respectively are also gases
,
but heavier.
As the carbon chain gets longer the substance turns first liquid (think octane -
 8
carbons), and then - eventually - solid (think paraffin wax).

So at some stage the length is such that a semi-solid substance results -
snotomers. I think you can guess why the name was applied. Think also the stuff
you
have to clean off a chip pan when the oil is getting tired. Or that has to gouge
d
out of key slots on pipes.

It is of course more complicated than that - the "bits hanging off the carbon
chains" are sometimes able to link with their neighbouring chains - if they didn
't
we wouldn't have plastic washing up bowls - and the exact consistency of any
particular plastic is determined  by these sort of linkages, and the exact proce
ss
by which they are produced.

In essence the number of chains there are"holding hands", the exact elements doi
ng
the linkages, and the length of the central chain determines the solidity or
otherwise of the material.

Does that help?

Julia



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