Kukho iintlobo ezimbini zeerubha: zendalo kunye nezokwenziwa. Irabha yendalo ivela kwilatex, incindi yobisi efumaneka kwizityalo ezikwiitropiki. Irabha yokwenziwa yenziwe ngepetroleum kwaye ayiveli kwizityalo.
Intshayelelo: yintoni na i-silicone kunye nerubha yendalo, kwaye yintoni umehluko obalulekileyo?
Irabha yendalo, evela kwi-latex yomthi we-Hevea brasiliensis, ibe ngowona mthombo werabha ukususela oko yafunyanwa ngabahloli bama-Euro-American eMzantsi Melika ngenkulungwane ye-16. I-Brazil yayiyeyona nto iphambili ekuboneleleni ngayo de kwaba ngoo-1860s xa amanye amazwe (ngokukodwa iMalaysia ne-Indonesia) aqalisa imveliso eninzi yemithi yerabha. Okwangoku, irabha yendalo iseyimveliso ebalulekileyo kuqikelelo lwemveliso yehlabathi jikelele malunga ne-14 yezigidi zeetoni ngo-2009. Irabha zokwenziwa zaphuhliswa ekuqaleni kweminyaka yoo-1900 ngempumelelo eyahluka-hlukeneyo kwaye akuzange kube kude kwade kwayiMfazwe Yehlabathi II apho zaye zaveliswa ngobuninzi ukuze zithathe indawo yazo. irabha yendalo kwizicelo ezininzi. Eyona rabha yokwenziwa iphumelele kakhulu yi-poly(cis-1,4-isoprene), okanye i-polyisoprene (IR), eneempawu ezibonakalayo kunye neekhemikhali ezifana kakhulu nezo zerabha yendalo.
imbali
Ukusetyenziswa kokuqala kwerabha ziinkcubeko zemveli zaseMesoamerica. Ubungqina bokuqala bezinto zakudala bokusetyenziswa kwemihla yerabha yendalo kwinkcubeko ye-Olmec, ngesiganeko ngendlela yeebhola. Irabha yayisetyenziswa ngamaMaya kunye neenkcubeko zama-Aztec - ngaphezu kokwenza iibhola ama-Aztec asebenzisa irabha ukwenza iimaski, iimbadada, kunye nezinye izinto. Iipropathi zokugxuma zerabha bezibalulekile kwimidlalo yebhola yaseMesoamerican efana ne-ulama, edlalwe ngabantu abaninzi ukuya kuma-2,000. Ngo-1700 BCE ii-Olmecs zazitshintshile zisuka ekwenzeni izinto zerabha zaya kuzisebenzisa njengendawo eyintsomi yokupeyinta imifanekiso.
Irabha yendalo yi-elastomer efumaneka kwi-latex. Le polima ayiqhelekanga kuba iqulunqwe ngokupheleleyo (ngaphandle kwezinto ezinqabileyo) ze-cis-1,4-polyisoprene, ingenalo i-unsaturation (oko kukuthi, iibhondi eziphindwe kabini) phakathi kwamatyathanga amabini aphambili adityaniswe kwii-athomu ezikufutshane kwikhonkco eliphambili. Amatyathanga acwangciswe ngolungelelwaniso luka-“S” olulodwa (jonga umfanekiso), olunika irabha yendalo ukunwebeka kwayo kuluhlu olubanzi lobushushu ukusuka kwindawo engaphantsi komkhenkce ukuya malunga ne-170 °C (340 °F).
imveliso
Irabha yeSilicone yenziwe ngeepolima ezizii-inorganic, okanye zokwenziwa, ngelixa irabha yendalo ivela kwilatex yezityalo ezithile. Ngokwemichiza, irabha ye-silicone yahlukile kwirabha yendalo ngenxa yobukho bamaqela e-methyl kumatyathanga e-silicone ngelixa irabha yendalo inamaqela e-vinyl kuphela kumatyathanga abo. Indawo yokunyanga irabha ye-silicone nayo yahlukile kuneyerabha yendalo. Iindawo zokunyanga ziindawo ezisecaleni komqolo wepolymer apho ukudibanisa ukudibanisa kuyenzeka khona. Kwiirubhi ze-silicone, i-thecnology isebenzisa i-silanes e-hydrolyzable njengeendawo zonyango, ngelixa iteknoloji yerabha yendalo isebenzisa iiathom zesulfure njengendawo yonyango.
Irabha yeSilicone yi-elastomer ye-inorganic eyenziwe ngesilicon kunye neoksijini. Ikwabizwa ngokuba yipolysiloxane. Ngokungafaniyo nerubha yendalo, irabha ye-silicone ayinayo ibhondi ephindwe kabini kumatyathanga ayo epolymer. Oku kuyenza ukuba ingachaphazeleki kakhulu kwi-oxidation kunye nokuthotywa bubushushu kunye nokukhanya kwelanga. Irabha ye-Silicone nayo inendawo yokunyibilika ephezulu kunerabha yendalo, iyenza ifaneleke ngakumbi izicelo eziphezulu zobushushu.
Irabha yendalo yi-elastomer ephilayo eyenziwe ngeeyunithi ze-isoprene. Inezibophelelo eziphindwe kabini kumatyathanga ayo epolymer, ezenza ukuba ichaphazeleke kwi-oxidation kunye nokuthotywa bubushushu kunye nokukhanya kwelanga. Irabha yendalo nayo inendawo yokunyibilika esezantsi kunerabha ye-silicone, iyenza ilunge kakhulu kwizicelo zobushushu obuphezulu.
Ukwakheka: iquka ntoni irabha nganye kwezi?
Ukuqulunqwa kweRubha yeSilicone
Irabha ye-Silicone yenziwe ngeepolymers ezine-Si-O-Si backbones. Ukongeza kwezi polymers, irabha ye-silicone ikwanazo nezongezo ezifana nezihluzi, ii-pigments, kunye neyeza. Ukubunjwa kwerabha ye-silicone inokwenziwa ngokwezifiso ukufezekisa iipropati ezithile.
Uninzi lweerubha ze-silicone zorhwebo zihlanjululwe, oku kuthetha ukuba baye baphathwa ngamachiza okanye ukushisa ukuphucula iimpawu zabo zomzimba. I-Vulcanization inika irabha ye-silicone ukuxhathisa kwayo kumaqondo obushushu aphezulu kwaye iyenza yomelele ngakumbi xa iyonke.
Ukuqulunqwa kweRabha yeNdalo
Irabha yendalo yenziwe ngeepolymers ezine-Isoprene backbones. Ezi polima zifumaneka kwincindi yemithi ethile, ingakumbi umthi we-Hevea brasiliensis. Ulwakhiwo lwabo lwemolekyuli luluhlu lweeathom zekhabhoni, ezineathom ezininzi zehydrogen ezincanyathiselwe kumatyathanga. Ezi athom zehydrogen zizo ezenza irabha yendalo ilastiki. Inkqubo efanayo (hydrogenation) isetyenziselwa ukwenza iirubha zokwenziwa.
Iipropati: zeziphi iimpawu ezibonakalayo abanazo?
Kukho iipropathi ezininzi eziphambili ezahlula irabha ye-silicone kwirubha yendalo. Enye kukuhlala kwayo; irabha ye-silicone inokumelana nobushushu obugqithisileyo, ukukhanya kwe-UV, kunye nokuvezwa kwe-Ozone ngaphandle kokuphuka, ngelixa irabha yendalo iya kuthotywa ngokuhamba kwexesha phantsi kwezi meko. Ukongeza, irabha ye-silicone ixhathisa kakhulu kwiikhemikhali kunerabha yendalo, iyenza ibe lolona khetho lukhethiweyo kwizicelo apho inokudibana neekhemikhali eziqatha okanye izinyibilikisi. Okokugqibela, irabha ye-silicone inoxinano olusezantsi kakhulu kunerabha yendalo, oko kuthetha ukuba ilula ngobunzima kwaye ibhetyebhetye ngakumbi. Ezi zakhiwo zenza irabha ye-silicone ibe yinto efanelekileyo kumashishini amaninzi kunye nabathengi.
Irabha ye-Silicone yi-elastomer eyenziwe nge-silicone-yona i-polymer-equlethe i-silicon kunye ne-carbon, i-hydrogen, kunye ne-oksijini. Irabha ye-Silicone inenani leenzuzo ezenza ukuba zilungele ukusetyenziswa kwizicelo ezininzi ezahlukeneyo.
Iyakwazi ukumelana nobushushu ngokugqithisileyo, okuthetha ukuba inokumelana namaqondo obushushu aphezulu ngaphandle kokuthotywa. Oku kuyenza igqibelele ukusetyenziswa kwizicelo apho kukho umngcipheko womonakalo wobushushu, njengaku silicone iigaskets zeemoto kunye nezitywini.
Irabha yeSilicone nayo inokumelana okubalaseleyo namaqondo obushushu abandayo. Oku kuyenza ilungele ukusetyenziswa kwizicelo apho kukho umngcipheko womonakalo obandayo, njengakwimigqomo yokugcina ukutya.
Irabha ye-Silicone nayo yomelele kakhulu. Ayithobi ngokuhamba kwexesha njengoko irabha yendalo isenza, oku kuthetha ukuba inobomi obude kakhulu. Oku kuyenza ilungele ukusetyenziswa kwizicelo apho ukuthembeka kwexesha elide kubalulekile, njengakwizixhobo zonyango.
Irabha yendalo yi-elastomer ekhutshwa kulwelo olumhlophe olubisi olubizwa ngokuba yilatex oluveliswa zizityalo ezininzi. Ibonisa iipropathi ezilungileyo zoomatshini ezinje nge-elasticity, ukuxhathisa kwe-abrasion, kunye namandla okuqina kunye nokuxhathisa okugqwesileyo kwamanzi kunye neempawu zokugquma umbane.
Impembelelo yokusingqongileyo: luhlobo luni lonyawo abanalo?
Iintlobo ezimbini eziphambili zeerubha ziyi-silicone kunye nerubha yendalo. Zombini zineendlela ezahlukeneyo zokusingqongileyo.
Irabha yendalo yenziwe ngencindi yemithi ethile, kwaye sisixhobo esihlaziyekayo. Iqhekeza ngokulula kwimekobume kwaye ayikhupheli i-toxins eyingozi. Imveliso yerabha yendalo ifuna umhlaba omninzi, nto leyo enokuba nefuthe elibi kwi-ikhosistim.
I-rubber ye-Silicone yenziwe kwizinto zokwenziwa kwaye ayisiyiyo into enokuphinda ihlaziywe. Ayiqhekeki lula kwindawo engqongileyo kwaye inokukhupha ityhefu eyingozi. Ukuveliswa kwerabha ye-silicone ayifuni umhlaba omkhulu, kodwa izinto zokwenziwa ezenziwe ngazo zinokuba yingozi kwindalo.
Ixabiso: zixabisa malini?
Iindleko zihlala ziyinto ebalulekileyo ekufuneka uyiqwalasele xa ukhetha imathiriyeli yeprojekthi yakho. Ngoko, ingakanani i-silicone kunye neerubha zendalo zibiza?
Irabha ye-Silicone ixabisa kakhulu kunerabha yendalo. Oku kungenxa yokuba irabha ye-silicone inokumelana nobushushu obungcono kunye nokumelana neekhemikhali kunerubha yendalo. Ukongeza, irabha ye-silicone inokumelana nobushushu obuphezulu kunerabha yendalo, iyenza ibe lolona khetho lukhethiweyo kwizicelo ezininzi.
Irabha yendalo, ngakolunye uhlangothi, ingabizi kakhulu kunerubha ye-silicone. Oku kungenxa yokuba irabha yendalo ayinakumelana nobushushu kunye neekhemikhali njengerabha ye-silicone. Nangona kunjalo, i-rubber yendalo ingasetyenziselwa uluhlu olubanzi lwezicelo kunerubha ye-silicone ngenxa yeendleko zayo eziphantsi.
Isiphelo: yeyiphi irabha engcono xa iyonke?
Zombini irabha ye-silicone kunye nerubha yendalo ineenzuzo kunye nokubi. Kuxhomekeke kwiimfuno zakho ezithile malunga nokuba yeyiphi eya kusebenza ngcono kuwe. Ukuba ufuna into enokumelana nokushisa okuphezulu, irabha ye-silicone yindlela yokuhamba. Ukuba ufuna i-material e-elastic ngakumbi kwaye inamandla aphezulu, ngoko irabha yendalo lolona khetho lungcono. Ekugqibeleni, eyona irabha ilungileyo kwiimfuno zakho ixhomekeke ekubeni zeziphi iimpawu ezibaluleke kakhulu kuwe.
