After partial evaporation of water, the salt solution was fed into an autoclave and heated to
285
degrees centigrade under a pressure of 250 pounds per square inch. Under these conditions,
polymerization took place. The water was bled off slowly and the pressure slowly reduced
to atmospheric levels. The molten polymer was then extruded from the autoclave. Making
one batch took about four hours.
Two additional chemicals were added during the process. Acetic acid stopped polymerization
when the molecules reached the desired length, while titanium dioxide (a delusterant) kept
the nylon from looking glassy, making the finished product appear more like silk.
Polymerization
Top of 250 pound autoclave at the semi-works
Reproduction from an original photograph
November, 1937
Gift of Joe Labovsky
