Vim li cas roj hmab yuav tsum tau vulcanized?Dab tsi yog cov txiaj ntsig ntawm vulcanizing roj hmab?Txawm hais tias cov roj hmab nyoos roj hmab kuj muaj qee qhov kev siv tau zoo, nws kuj muaj ntau yam tsis zoo, xws li tsis muaj zog thiab elasticity tsawg;Txias ua rau nws nyuaj, kub ua rau nws nplaum;Yooj yim rau hnub nyoog, thiab lwm yam Raws li earl...
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