And then World War II Happened
DuPont had been working throughout the 1930s to find a way to mass-produce and commercialize its invention. The U.S. economy, suffering in the wake of the 1929 stock market crash, would benefit from a domestically-made substitute for rubber. When the war effort began in earnest, however, the need for a synthetic material to use for making equipment became extremely important.
DuPrene was renamed neoprene in 1936. The generic name reflected the fact that neoprene wasn't an end product, but a component that could be used in any number of items. And during World War II, it was used in hoses, tires, gaskets, and many other non-metal vehicle parts.
In fact, during World War II, U.S. neoprene was only used for making equipment for the war.