Muaj ob hom roj hmab: ntuj thiab hluavtaws. Cov roj hmab ntuj yog los ntawm latex, ib qho kua mis uas muaj nyob rau hauv cov nroj tsuag tropical. Cov roj hmab hluavtaws yog tsim los ntawm cov khoom siv roj av thiab tsis yog los ntawm cov nroj tsuag.
Taw qhia: silicone thiab roj hmab ntuj yog dab tsi, thiab dab tsi yog qhov sib txawv tseem ceeb?
Cov roj hmab ntuj, los ntawm latex ntawm Hevea brasiliensis tsob ntoo, yog lub hauv paus ntawm cov roj hmab txij thaum nws nrhiav tau los ntawm Euro-American explorers nyob rau hauv South America nyob rau hauv lub xyoo pua 16th. Brazil yog tus xa khoom tseem ceeb mus txog rau xyoo 1860 thaum lwm lub tebchaws (xws li Malaysia thiab Indonesia) pib tsim cov ntoo roj hmab ntau. Tam sim no, cov roj hmab ntuj tseem yog cov khoom lag luam tseem ceeb nrog kev kwv yees thoob ntiaj teb kev tsim khoom ntawm ib ncig ntawm 14 lab tons hauv 2009. Synthetic rubbers tau tsim nyob rau thaum ntxov 1900s nrog ntau yam kev vam meej thiab nws tsis yog txog rau thaum Ntiaj Teb Tsov Rog II uas lawv tau tsim ntau los hloov. ntuj roj hmab hauv ntau daim ntawv thov. Cov roj hmab hluavtaws zoo tshaj plaws yog poly (cis-1,4-isoprene), lossis polyisoprene (IR), uas muaj lub cev thiab tshuaj lom neeg zoo ib yam li cov roj hmab ntuj.
Keeb kwm
Thawj qhov kev siv roj hmab yog los ntawm cov haiv neeg hauv paus txawm ntawm Mesoamerica. Cov pov thawj archaeological ntxov tshaj plaws ntawm kev siv cov roj hmab ntuj hnub rau Olmec kab lis kev cai, xwm txheej nyob rau hauv daim ntawv ntawm pob. Roj hmab tau siv los ntawm Maya thiab Aztec kab lis kev cai - ntxiv rau kev ua pob Aztecs siv roj hmab los ua lub ntsej muag, khau khiab, thiab lwm yam khoom. Cov khoom sib tw ntawm cov roj hmab yog qhov tseem ceeb rau Mesoamerican pob ua si xws li ulama, uas tau ua si los ntawm ntau txog 2,000 tus neeg. Los ntawm 1700 BCE Olmecs tau hloov pauv los ntawm kev ua cov khoom siv roj hmab los siv nws ua qhov nruab nrab tsis tseeb rau kev pleev xim duab.
Ntuj roj hmab yog elastomer uas tau los ntawm latex. Qhov no polymer yog txawv nyob rau hauv uas nws yog tsim tag nrho (nrog tsawg tsawg) ntawm cis-1,4-polyisoprene, tsis muaj unsaturation (uas yog, ob daim ntawv cog lus) ntawm ob lub ntsiab chains bonded rau cov atoms uas nyob ib sab nyob rau hauv lub ntsiab saw. Cov chains yog teem rau hauv ib tus neeg "S" configurations (saib duab), uas muab cov roj hmab ntuj nws elasticity nyob rau hauv ib tug dav kub ntawm qhov kub ntawm qhov chaw txias mus txog 170 ° C (340 ° F).
Qhuav
Silicone roj hmab yog tsim los ntawm inorganic, los yog hluavtaws, polymers whereas ntuj roj hmab los ntawm latexes ntawm tej nroj tsuag. Chemically, silicone roj hmab yog txawv ntawm cov roj hmab ntuj vim muaj cov methyl pawg nyob rau hauv silicone chains whereas ntuj roj hmab tsuas muaj vinyl pawg nyob rau hauv lawv chains. Qhov chaw kho ntawm silicone roj hmab kuj txawv dua li cov roj hmab ntuj. Cov chaw kho mob yog qhov chaw nyob ntawm cov pob txha polymer uas qhov kev sib txuas tuaj yeem tshwm sim. Hauv cov roj hmab silicone, thecnology siv hydrolyzable silanes ua qhov chaw kho mob, thaum nyob rau hauv natural rubbers technology siv sulfur atoms ua qhov chaw kho.
Silicone roj hmab yog ib qho inorganic elastomer tsim ntawm silicon thiab oxygen. Nws tseem hu ua polysiloxane. Tsis zoo li cov roj hmab ntuj, silicone roj hmab tsis muaj ob daim ntawv cog lus hauv nws cov saw hlau polymer. Qhov no ua rau nws tsis tshua muaj oxidation thiab degradation los ntawm tshav kub thiab tshav ntuj. Silicone roj hmab kuj muaj cov ntsiab lus melting ntau dua li cov roj hmab ntuj, ua rau nws haum rau kev siv kub kub.
Cov roj hmab ntuj yog cov organic elastomer uas muaj cov isoprene units. Nws muaj ob daim ntawv cog lus hauv nws cov saw hlau polymer, uas ua rau nws raug oxidation thiab degradation los ntawm tshav kub thiab tshav ntuj. Cov roj hmab ntuj kuj muaj qhov qis qis dua li cov roj hmab silicone, ua rau nws tsis haum rau cov ntawv thov kub.
Muaj pes tsawg leeg: txhua yam ntawm cov roj hmab no muaj li cas?
Kev sib xyaw ntawm Silicone Rubber
Silicone roj hmab yog tsim los ntawm polymers nrog Si-O-Si qaum. Ntxiv nrog rau cov polymers no, silicone roj hmab kuj muaj cov additives xws li fillers, pigments, thiab curatives. Cov muaj pes tsawg leeg ntawm silicone roj hmab tuaj yeem hloov kho kom ua tiav cov khoom tshwj xeeb.
Feem ntau ntawm cov khoom lag luam silicone roj hmab yog vulcanized, txhais tau hais tias lawv tau raug kho nrog tshuaj los yog cua sov los txhim kho lawv lub cev. Vulcanization muab silicone roj hmab nws tsis kam mus rau qhov kub thiab txias thiab ua rau nws ruaj khov tag nrho.
Kev sib xyaw ntawm Natural Rubber
Cov roj hmab ntuj yog tsim los ntawm polymers nrog Isoprene qaum. Cov polymers no muaj nyob rau hauv cov kua txiv ntawm qee cov ntoo, tshwj xeeb tshaj yog tsob ntoo Hevea brasiliensis. Lawv cov qauv molecular yog cov saw hlau ntawm carbon atoms, nrog ob peb hydrogen atoms txuas rau cov chains. Cov hydrogen atoms no yog dab tsi ua rau cov roj hmab ntuj elastic. Tib txheej txheem (hydrogenation) yog siv los ua cov roj hmab hluavtaws.
Cov khoom: lawv muaj lub cev dab tsi?
Muaj ntau yam khoom tseem ceeb uas paub qhov txawv ntawm silicone roj hmab los ntawm cov roj hmab ntuj. Ib qho yog nws cov kav ntev; silicone roj hmab tuaj yeem tiv taus qhov kub thiab txias, UV teeb, thiab Ozone raug tsis tawg, thaum cov roj hmab ntuj yuav degrade nyob rau lub sijhawm raws li cov xwm txheej no. Tsis tas li ntawd, cov roj hmab silicone muaj peev xwm tiv taus cov tshuaj ntau dua li cov roj hmab ntuj, ua rau nws qhov kev xaiv zoo tshaj plaws rau cov ntawv thov uas nws tuaj yeem cuam tshuam nrog cov tshuaj hnyav lossis cov kuab tshuaj. Thaum kawg, silicone roj hmab muaj qhov ntom ntom dua li cov roj hmab ntuj, lub ntsiab lus nws yog qhov sib dua ntawm qhov hnyav thiab hloov tau yooj yim dua. Cov khoom no ua rau cov roj hmab silicone yog cov khoom siv zoo tshaj plaws rau ntau yam kev lag luam thiab cov neeg siv khoom.
Silicone roj hmab yog ib qho elastomer tsim los ntawm silicone-nws tus kheej yog polymer-muaj silicon ua ke nrog carbon, hydrogen, thiab oxygen. Silicone roj hmab muaj ntau cov txiaj ntsig uas ua rau nws zoo tagnrho rau kev siv ntau yam kev siv.
Nws yog qhov tsis tshua muaj cua sov, txhais tau tias nws tuaj yeem tiv taus qhov kub thiab txias yam tsis muaj degrading. Qhov no ua rau nws zoo meej rau kev siv hauv cov ntawv thov uas muaj kev pheej hmoo ntawm kev puas tsuaj thaum tshav kub kub, xws li hauv silicone automotive gaskets thiab sealants.
Silicone roj hmab kuj muaj kev tiv thaiv zoo rau qhov txias txias. Qhov no ua rau nws zoo tagnrho rau siv rau hauv cov ntawv thov uas muaj kev pheej hmoo ntawm kev puas tsuaj rau khaub thuas, xws li hauv cov thawv ntim khoom noj.
Silicone roj hmab kuj tseem ruaj khov. Nws tsis degrade lub sij hawm zoo li cov roj hmab ntuj, txhais tau tias nws muaj lub neej ntev dua. Qhov no ua rau nws zoo meej rau kev siv hauv cov ntawv thov uas qhov kev ntseeg tau ntev ntev yog qhov tseem ceeb, xws li hauv cov khoom siv kho mob.
Cov roj hmab ntuj yog ib qho elastomer uas tau muab rho tawm los ntawm cov kua mis dawb hu ua latex uas yog tsim los ntawm ntau cov nroj tsuag. Nws nthuav tawm cov khoom zoo xws li elasticity, abrasion tsis kam, thiab tensile lub zog nrog rau cov dej tsis zoo thiab hluav taws xob rwb thaiv tsev.
Environmental cuam tshuam: hom hneev taw lawv muaj li cas?
Ob hom roj hmab tseem ceeb yog silicone thiab roj hmab ntuj. Lawv ob leeg muaj qhov sib txawv ib puag ncig hneev taw.
Cov roj hmab ntuj yog tsim los ntawm cov kua txiv hmab txiv ntoo ntawm qee yam ntoo, thiab yog cov khoom siv txuas ntxiv. Nws tawg yooj yim nyob rau hauv ib puag ncig thiab tsis tso cov co toxins. Kev tsim cov roj hmab ntuj xav tau ntau thaj av, uas tuaj yeem cuam tshuam tsis zoo rau ecosystems.
Silicone roj hmab yog tsim los ntawm cov khoom siv hluavtaws thiab tsis yog cov khoom siv txuas ntxiv. Nws tsis tawg yooj yim hauv ib puag ncig thiab tuaj yeem tso tawm cov co toxins. Kev tsim cov roj hmab silicone tsis xav tau ntau thaj av, tab sis cov khoom siv hluavtaws uas nws yog tsim los ntawm yuav ua rau muaj kev phom sij rau ib puag ncig.
Tus nqi: lawv them ntau npaum li cas?
Tus nqi ib txwm yog qhov tseem ceeb uas yuav tsum tau xav txog thaum xaiv cov khoom siv rau koj qhov project. Yog li, pes tsawg tus nqi silicone thiab roj hmab ntuj?
Silicone roj hmab feem ntau kim dua li cov roj hmab ntuj. Qhov no yog vim cov roj hmab silicone muaj cov cua sov zoo dua thiab cov tshuaj tiv thaiv zoo dua li cov roj hmab ntuj. Tsis tas li ntawd, cov roj hmab silicone tuaj yeem tiv taus qhov kub thiab txias dua li cov roj hmab ntuj, ua rau nws xaiv rau ntau daim ntawv thov.
Cov roj hmab ntuj, ntawm qhov tod tes, tsis tshua kim dua li silicone roj hmab. Qhov no yog vim cov roj hmab ntuj tsis tiv taus cua sov thiab tshuaj lom neeg li silicone roj hmab. Txawm li cas los xij, cov roj hmab ntuj tuaj yeem siv rau ntau yam kev siv ntau dua li cov roj hmab silicone vim nws cov nqi qis dua.
Cov ntsiab lus: cov roj hmab twg zoo dua tag nrho?
Ob leeg silicone roj hmab thiab cov roj hmab ntuj muaj lawv qhov zoo thiab qhov tsis zoo. Nws yeej nyob ntawm koj qhov kev xav tau tshwj xeeb raws li qhov twg yuav ua haujlwm zoo dua rau koj. Yog tias koj xav tau cov khoom siv uas tuaj yeem tiv taus qhov kub thiab txias, ces silicone roj hmab yog txoj hauv kev mus. Yog tias koj xav tau cov khoom siv uas muaj zog dua thiab muaj zog tensile ntau dua, cov roj hmab ntuj yog qhov kev xaiv zoo dua. Thaum kawg, cov roj hmab zoo tshaj plaws rau koj cov kev xav tau yog nyob ntawm seb tus cwj pwm tseem ceeb tshaj plaws rau koj.
