Vulcanize is a term that refers to the process of treating rubber or similar materials with sulfur to make them more durable and flexible. However, there are other words that can be used as synonyms for this process. These include curing, hardening, solidifying, or strengthening. All of these words highlight the fact that the process of vulcanizing makes the material more resilient and long-lasting. Other synonyms for vulcanize also include fortify, reinforce, toughen, and build up. Each of these words emphasizes the idea that the material has been made stronger and more resilient, making it more useful for a wide range of different applications.