Hauv cov roj hmab kev lag luam uas hu ua Txau Tsuag, yog vim yog ib feem los sis tag nrho cov khoom siv roj hmab uas muaj cov khoom siv hauv cov pob zeb saum txaj, kev ywj ntsws ua rau lub pob txha zoo li, cov tshuaj nplaum yog siv tshuaj ntxhua khaub ncaws, Roj hmab yog leej faj.
Cov tshuaj yog: tag nrho tov, yog li ntawd tus neeg saib xyuas kev sib txuas lus faib rau tusyees. Qhov zoo sib ntxiv ntawm cov ntoo thuv hauv cov roj hmab thiab kua coumarone kuj tuaj yeem ua rau kom muaj teeb meem los ntawm cov khi kom txo tau qhov tshwm sim ntawm cov tshuaj tsuag tsuag.
Cov tsos ntawm cov huab-zoo li lossis cov hmoov tshuaj dawb rau ntawm cov khoom siv roj hmab vim kev tsiv ntawm cov kua losyog khoom hauv ib qho chaw lossis cov ntaub nplaum nplaum. Qhov no yog vim kev siv cov leej faj, cov khauj khiab mis, qee cov neeg laus muaj hnub nyoog, thiab cov neeg muag muag muag kom dhau lawv cov kua dej nyob hauv roj hmab. Yuav kom tiv thaiv tau kab tsuag, qhov saum toj no ntau npaum li cas ntawm cov dej sib tov yuav tsum tsim nyog, rau hom khaub thuas hnyuv-daj tsuag nplaum yuav siv tau los tiv thaiv kev siv cov tshuaj tsis muaj dej.
Tshuaj txau kuj paub tias yog tshuaj tsuag (tawg paj), yog cov roj hmab ua haujlwm ntawm cov teeb meem zoo, nws yog hais txog cov ntaub nplaum lossis cov ntaub nplaum los ntawm tus neeg sawv cev ntawm cov neeg sawv cev mus rau qhov teeb meem saum npoo thiab dej nag. Qee lub sij hawm cov tshuaj tsuag yog cov pob txha xws li pob txha, xws li nws hu ua "nws cov tshuaj tsuag." Feem ntau ntawm Frost yog leej faj, vim hais tias leej faj yog feem ntau dav siv nyob rau hauv dav roj hmab vulcanizing tus neeg sawv cev, thiab nyob rau hauv qhov tsawg solubility ntawm rubber thiaj li yooj yim los tsim tshuaj tsuag. Qhov tseeb, ntawm qhov pom ntawm cov tshuaj tsuag, nws tsis tas yuav tsum ua kom zoo, tab sis kuj muaj roj (xws li muag muag, yas thawv) los yog hmoov (ntau dua cov neeg tuaj yeem, cov neeg laus, cov neeg muag khoom txhawb, lwm yam) cov pa roj dub tawm kuj pom.