Meaning of over-vulcanize in English:
over-vulcanize
Pronunciation /ˌəʊvəˈvʌlkənʌɪz/
verb
(also overvulcanise)
To subject to over-vulcanization; to make (rubber) hard or brittle by excessive vulcanizing; to overcure (rubber).
Origin
Early 20th century. From over- + vulcanize.