nelsonB
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Nylon Family
Hi
i was looking about the synthesis of Nylon-6-6
using hexamethylenediamine and hexanedioic acid but since i said to my self both of those component have 6 carbon atom in it
why not making something like like 2 atom in it such using oxalic acid
and i found a text talking about the synthesis of Nylon-4,2
http://doc.utwente.nl/70783/1/Gaymans84preparation.pdf
alternatively i guess i could be possible to make something such
Nylon-2,2 with Ethylenediamine and Oxalyl chloride
give your idea about that and what would you think about its property if its could be better or worse than Nylon-6-6
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Nicodem
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Quote: Originally posted by nelsonB  | alternatively i guess i could be possible to make something such
Nylon-2,2 with Ethylenediamine and Oxalyl chloride
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I don't see how the reaction between ethylenediamine and oxalyl chloride could give nylon-2,2. I see no reason why these would not react to give the
expected product instead, the piperazine-2,3-dione. I would expect the synthesis is quite different - assuming it is a stable polymer at all (I would
expect it to easily depolymerize under the influence of traces of bases or acids, or heat). Do you have any reference for such a synthesis of
nylon-2,2?
| Quote: | | give your idea about that and what would you think about its property if its could be better or worse than Nylon-6-6 |
Give you ideas? Are you interested in the properties of the material or in ideas only? If you are interested in properties, then check them in the
literature - again presuming that such polymer even exists.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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12AX7
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'Spose it's worth contemplating: what prevents Nylon-6,6 from being a cyclic di- or oligomer itself? Could a catalyst be used to encourage
polymerization, like making poly lactic acid?
Tim
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UnintentionalChaos
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| Quote: Originally posted by 12AX7 | 'Spose it's worth contemplating: what prevents Nylon-6,6 from being a cyclic di- or oligomer itself? Could a catalyst be used to encourage
polymerization, like making poly lactic acid?
Tim |
Ring sizes above 5-6 are not very favorable energetically. This is why one can easily turn 7-membered caprolactam into nylon-6 by ring opening
polymerization.
Then again, with the right catalyst, even things like THF can be converted into a polymer. However, I think most current nylons benefit from long
aliphatic segment as far as pliability and limited crystallinity are concerned.
Nylon 2,2 would have oxalic acid as a base unit instead of the weaker (pKa wise), longer chain or aromatic carboxylic acids used in other nylons. This
would probably make the amide linkages more susceptible to attack by nucleophiles and cause chain cleavage leading to premature breakdown of the
material.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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nelsonB
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yeah about the piperazine-2,3-dione i was thinking about that problem
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Dr.Bob
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The shorter the alkyl linker, the more rigid the polymer, I would expect. The polar regions of the molecule would also become a larger proportion of
the polymer, making it more polar in general, which would also contribute to more rigid and higher melting.
Most polymers use longer chained monomers to help encourage oligomers rather than dimers, as mentioned above. You may be able to find some sources
of adipic acid and perhaps some diamines if you look around, but making the polymer in a visible demo really requires the acid chloride, but that can
be made using the oxalyl chloride to make the di acid chloride of the adipic acid.
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