1930 Fluorocarbons synthesized and commercialized over the next few years as refrigerants by the Kinetic Chemical Corporation.
Plunkett, R.J. (1986). The History of Polytetrafluoroethylene: Discovery and Development. In: Seymour, R.B., Kirshenbaum, G.S. (eds) High Performance Polymers: Their Origin and Development. Springer, Dordrecht.
1933 PVC blended with additives, including phthalates, to make it into a useful plastic by Dr. Waldo Semon and the B.F. Goodrich Company.
US patent 1929453, Waldo Semon, “Synthetic rubber-like composition and method of making same,” published 1933-10-10, assigned to B.F. Goodrich