Nylon rope trick

Acid chloride preparative route to nylon-6,10

The nylon rope trick is a scientific demonstration that illustrates some of the fundamental chemical principles of step-growth polymerization and provides students and other observers with a hands-on demonstration of the preparation of a synthetic polymer.

The nylon rope trick typically makes use of a water solution of an aliphatic diamine with a solution of an aliphatic diacid chloride in a solvent that does not dissolve in water, yielding a synthetic polyamide of the nylon-type. Nylon 6-10 is commonly used, in which hexamethylene diamine is dissolved in water to a concentration of about 0.40 moles / deciliter. A solution of sebacoyl chloride in cyclohexane (0.15 moles / deciliter concentration) is then layered on top of the water solution, the reaction typically being conducted in a beaker. The solution is not agitated; instead the nylon-6,10 polymer forms as a flexible film at the interface of the water and cyclohexane layers, in an example of an interfacial polymerization.^[1] The experimentalist grasps the polymer film, withdrawing it from the reaction vessel, forming a filament or rope, and collecting it on a rotating rod above the reaction vessel. New polymer forms at the interface as fresh surfaces of the cyclohexane layer and the water layer form. In this way, the demonstration yields a continuous rope that is collected on the rotating rod. Nylon 6-6 can also be produced at laboratory scale in this way.

Representative procedures and equipment lists for conducting the nylon rope trick demonstration are available in literature procedures.^[2]

The nylon rope trick was developed as a scientific demonstration by American inventor Stephanie Kwolek.

Gallery

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  Nylon-6,6

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  The nylon is pink because the solution has an indicator dye in it.

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  A nylon strand, synthesised by young scientists at XLAB international science camp 2012 August

External Links

• Videos demonstrating the Nylon Rope Trick are available on-line.

References

1. ↑ MacRitchie, F. (1969). Transactions of the Faraday Society 63: 2503.  Missing or empty |title= (help); |accessdate= requires |url= (help)
2. ↑ Lister, Ted (1995). Classic Chemistry Demonstrations. London: The Royal Society of Chemistry. p. 159. ISBN 1 870 343 387. Retrieved 3 January 2015.