Caprolactam from polyamide 6 (from old records)
A total of 10 kilograms of polyamide 6 with 30% glass fiber PA6 GF 30 were pyrolyzed several times in a paint can and a furnace made from a steel
barrel
Only 1.3 liters of liquid were obtained. The liquid was dissolved in 3 liters of water, the oily layer was separated, and then the aqueous solution
was washed with toluene and filtred.
The aqueous layer was evaporated in a metal container until evaporation decreased. About 1.5 liters of black syrup liquid with an unpleasant odor was
obtained. This is dirty conc solution caprolactam. It can be purified, for example, with an oxidizer. The small yield is probably due to direct
pyrolysis. When using, for example, catalytic pyrolysis with an acid or alkaline catalyst, the yield can be increased
However, I do not know the use of caprolactam, so this synthesis is of little value, but perhaps someday it will be useful to someone
There is also work on polyamide 66, which I will probably post soon. Hydrolysis in hydrochloric acid destroys the plastic in a couple of months,
turning it into something like old rubber. When heated, for example, in an oven, this reaction can be carried out in a couple of days to a week.
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