Room temperature vulcanized. In the old days, vulcanizing was achieved with heat. The class of rubber that we use is vulcanized at room temperature. Absolutely, but it probably won't cause a problem if you use the terms interchangeably. Urethanes are crystalline structures, and polyurethanes are not.
Urethanes are rigid and less prone to flexing.
Polyurethanes have chain extenders in their structures that allow them to bend and flex. At Accelerated Technologies, we use both urethane and polyurethane, matching the material to your unique needs. 10 to 30 parts. The liquid urethane produces an exothermic reaction as it goes from liquid to solid. The heat generated degrades the rubber, causing it to become brittle and unusable.