2024 Tus sau: Howard Calhoun | [email protected]. Kawg hloov kho: 2023-12-17 10:28
Nitrile butadiene roj hmab (NBR) yog cov khoom siv tseem ceeb rau kev tsim cov roj hmab ntau yam nrog kev ua haujlwm zoo. Nws yog cov khoom siv hluavtaws polymeric tau los ntawm copolymerization ntawm butadiene nrog acrylonitrile (NAC). Nws tuaj yeem hu ua nitrile, divinyl-nitrile, butadiene-acrylonitrile roj hmab lossis butacryl. Hauv kev tsim qauv thoob ntiaj teb, cov khoom siv no tau sau npe NBR (nitrile-butadienerubber), nyob rau hauv kev xaiv hauv tsev - SKN (nitrile hluavtaws roj hmab).
Qhov twg muaj feem
Hom roj hmab no feem ntau siv rau hauv cov kev lag luam uas qhov kev pom zoo ntawm cov khoom siv roj hmab rau cov tshuaj lom neeg yog qhov tseem ceeb. Qhov tseem ceeb tshaj plaws yog cov khoom ntawm butadiene-nitrile roj hmab li siab elasticity thiab me me mus tas li deformation. Cov khoom no yog davsiv rau hauv cov khoom siv roj hmab uas muaj kev sib cuag ncaj qha nrog cov khoom siv tshuaj lom neeg - cov no tuaj yeem ua tau txhua yam ntawm cov ntsaws ruaj ruaj, roj foob, roj hmab compensators, roj thiab roj hoses, tsav siv, roj tank rau tsheb, aviation thiab roj industries, luam tawm offset daim phiaj thiab lwm yam khoom.
Cov khoom raws li cov roj hmab no tsis o hauv cov kua roj, tshuaj tiv thaiv kab mob thiab dej. Los ntawm qee yam ntawm cov khoom siv no, cov hlua hluav taws xob thiab cov hnab looj tes roj hmab tau tsim, uas muaj lub zog tshwj xeeb thiab hnav tsis kam. Nws yog siv nyob rau hauv zus tau tej cov adhesives, sealants thiab polyurethane ua npuas ncauj. Roj hmab yog lub hauv paus hauv kev tsim cov nplaum.
Thaum twg thiab qhov twg yog cov roj hmab no tuaj ntawm?
Tau txais cov roj hmab butadiene-nitrile tau sau tseg hauv xyoo 1934 hauv Tebchaws Yelemees. Lub sijhawm ntawd, cov kws tshawb fawb German tau tsim cov khoom tshwj xeeb hauv nws cov khoom thiab patented nws nyob rau hauv lub npe Buna-N. Thaum Ntiaj Teb Tsov Rog II, cov khoom siv tshiab tau xav tau ntau hauv kev lag luam tub rog.
Vim vim tsis muaj cov khoom siv ntuj tsim, Asmeskas cov thawj coj saum toj kawg nkaus tau tsim ib txoj haujlwm tshwj xeeb uas koom nrog kev tsim cov roj hmab butadiene-nitrile thiab lwm yam khoom siv hluavtaws rau cov khoom siv roj hmab. Cov khoom tsim los ntawm txoj haujlwm no hu ua GR-N. Txog rau tam sim no, BNR tau dhau los ua ib qho ntawm feem ntau nrhiav-tom qab cov roj hmab tshwj xeeb. Nws yog tsim nyob rau hauv ntau tshaj 20 lub teb chaws thoob ntiaj teb.
NBR production
Cov khoom siv no tau txais los ntawm kev tsim cov polymerization hauv cov dej emulsion. Cov txheej txheem yog nqa tawm ob qho tib si ntawm qhov kub thiab txias. Lub ntsiab monomers rau lawv cov khoom yog butadiene-1, 3 thiab acrylic acid nitrile (NAC), sib tov nyob rau hauv ib qho kev faib ua feem. Cov tshuaj no tsis nyob ntawm qhov kub thiab txias. Ua raws li cov cai ntawm random copolymerization, nws yuav tsum tau muab sau tseg tias qhov tandem ntawm monomers yuav tsum muaj cov khoom ntawm azeotropic muaj pes tsawg leeg uas muaj li ntawm 40% acrylonitrile nyob rau hauv ib tug sib tov ntawm monomers.
Hauv kev tsim cov roj hmab no, yuav tsum muaj kev ua kom huv huv ntxiv thaum lub sijhawm coagulation ntawm cov emulsifiers siv rau polymerization. Hauv cov khoom siv roj hmab, ib qho me me ntawm tshauv, ntxhia thiab tsis muaj kuab lom (tsis ntau tshaj 1%) raug tso cai. Lawv tuaj yeem thauj khoom nrog cov tshuaj tiv thaiv kab mob tsis ruaj khov lossis tsis ruaj khov.
BNK yog dab tsi
Hauv peb lub tebchaws, cov roj hmab xws li nitrile roj hmab-18 (SKN-18), nitrile-butadiene roj hmab-26 (SKN-26) thiab nitrile butadiene roj hmab-40 (SKN-40) yog tsim. Tus lej ntsuas hauv qib qhia cov lej ntawm acrylonitrile units hauv polymers. Lawv tuaj yeem muaj 18%, 26% lossis 40% Acrylonitrile, raws li.
Hloov cov naj npawb ntawm cov khoom xyaw, koj tuaj yeem ua tiav cov khoom sib txawv ntawm cov khoom tsim tawm. Nyob ntawm qhov feem pua ntawm acrylonitrile, cov khoomCov roj hmab tuaj yeem sib txawv hauv hardness, viscosity, roj - thiab roj tsis kam. Qhov feem pua ntawm NAC cuam tshuam rau qhov cuam tshuam ntawm cov qauv ntawm cov qauv. Nws yog qhov tseem ceeb no uas cuam tshuam rau kev siv cov roj hmab nitrile butadiene hauv qee thaj chaw ntawm kev lag luam hauv tebchaws. Txawm li cas los xij, nws yog siv los ua cov khoom siv raw rau kev tsim khoom ntawm ntau yam khoom siv roj hmab.
Khoom tsis zoo
Txawm hais tias cov khoom siv roj hmab ua nrog sib ntxiv ntawm BNR muaj tag nrho cov kev ua tau zoo (siab tensile zog thiab ductility, txheeb ze elongation, tsim kua muag thiab abrasion tsis kam, zoo heev roj thiab roj kuj), cov khoom no thiab ib co flaws.
Tougher kev khiav hauj lwm tej yam kev mob txuam nrog ib tug nce nyob rau hauv lub ceev ntawm mechanisms thiab tsis muaj cov roj txias, ua rau lub fact tias cov roj hmab cov ntsiab lus tsuas yog ua hauj lwm ntawm kub txog +150 degrees. Thaum qhov kev khiav hauj lwm kub nce siab tshaj tus nqi no, kev teeb tsa tshwm sim, thiab tom qab ntawd kev puas tsuaj ntawm cov roj hmab tsim los ntawm NBR. Nyob rau hauv lwm yam lus, rhuab roj hmab yuav nyuaj thiab nkig.
raug rau qhov kub thiab txias kuj muaj qhov tsis zoo rau cov khoom siv roj hmab, uas tau siv los ua cov roj hmab nitrile. Qhov zoo tshaj plaws kev khiav hauj lwm kub rau lawv yog suav tias yog tsis qis tshaj -35˚С.
Kev hloov kho roj hmab niaj hnub
Tsim cov khoom siv roj hmab nrogib txheej tshwj xeeb ntawm cov khoom, kev hloov kho niaj hnub ntawm cov roj hmab siv ntau dua. Hydrogenated nitrile butadiene roj hmab yog suav hais tias yog ib qho kev cog lus loj hlob hauv kev hloov kho. Lawv muaj cov khoom ua tau zoo hauv ntau hom roj hmab ntau lawm.
Roj hmab ua los ntawm polyvinylchloride-hloov rubbers muab kev ua haujlwm ruaj khov hauv huab cua hnav tsis kam (txog -50 degrees) thiab huab cua ua haujlwm kub txog +160 degrees. Nws yog qhov zoo tshaj rau cov khoom tsim los ntawm nitrile rubbers nyob rau hauv cov nqe lus ntawm kev tsim kua muag thiab hnav tsis kam. Nws muaj kev tiv thaiv zoo heev rau kev cuam tshuam ntawm cov tshuaj lom neeg nruj heev. Txawm li cas los xij, cov roj hmab no tsis muaj zog thiab elastic. Yog li ntawd, txhawm rau txhim kho kev ua haujlwm ntawm cov khoom siv, nws feem ntau yog siv ua ke nrog cov pa roj hmab nitrile.
Vulcanization
txheej txheem ntawm vulcanization ntawm butadiene-nitrile rubbers yog ua los ntawm kev siv sulfur, nrog rau thiuram, organic peroxides, alkylphenol-formaldehyde resins thiab organochlorine tebchaw. Qhov kub tuaj yeem sib txawv ntawm 140˚ txog 190˚ Celsius. Thaum lub sij hawm tus txheej txheem no, ib tug loj toj siab ntawm vulcanization yog pom. Cov ntsiab lus ntxiv ntawm NAC pab txhawb rau qhov nce ntawm tus nqi ntawm vulcanization. Qhov zoo ntawm cov khoom siv roj hmab yog ntsuas los ntawm cov yam ntxwv ntawm cov vulcanizers.
Properties
BNC cov khoom raug txiav tximcov ntsiab lus acrylonitrile. Hom roj hmab no yog soluble hauv ketones, qee cov tshuaj hydrocarbon thiab esters. Aliphatic hydrocarbons thiab cawv tsis muaj kev cuam tshuam rau kev tawg ntawm nitrile butadiene roj hmab. Kev nce ntxiv ntawm cov khoom siv acrylonitrile pab txhawb kev sib cuam tshuam ntawm cov saw hlau polymer: ntau NAA nyob rau hauv cov khoom muaj pes tsawg leeg, siab dua qhov ceev thiab kub ntawm cov iav hloov pauv. Cov ntsiab lus ntau ntxiv ntawm NAA txo cov dielectric zog, txo cov qib ntawm solubility hauv cov kuab tshuaj tsw qab thiab ua rau muaj kev tiv thaiv o hauv aliphatic hydrocarbons.
Nyob ntawm cov txheej txheem ntawm polymerization ntawm roj hmab, nws tuaj yeem tsim nrog cov khoom sib txawv ntawm cov plastoelastic. Lawv tuaj yeem yog:
- Ntau nyuaj (Defoe hardness 21.5 - 27.5 N). Thaum kos cov roj hmab no, tsab ntawv "T" ntxiv rau nws lub npe.
- Solid (Defoe hardness 17.5 - 21.5 N).
- Mos (Defoe hardness 7.5 - 11.5 N). Thaum kos cov roj hmab no, tsab ntawv "M" ntxiv rau nws lub npe.
Rau NBRs tsim nrog alkylsulfonates ua emulsifiers, tsab ntawv "C" ntxiv rau qhov cim. Piv txwv li, SKN-26MS yog cov roj hmab muag uas muaj 26% khi NAC, thiab biodegradable alkyl sulfonate emulsifier tau siv rau hauv kev npaj.
Pom zoo:
Tung roj: ntau lawm, daim ntawv thov, khoom, tshuaj xyuas
Tung roj tau ntev tau siv los ua cov khoom siv ntoo. Rau ntau centuries, nws tau tsim nws tus kheej raws li ib tug zoo heev preservative, antiseptic, nrog zoo nkauj zoo nkauj
Roj ntau lawm hauv ntiaj teb. Roj ntau lawm nyob rau hauv lub ntiaj teb no ( rooj)
Lub ntiaj teb li peb paub nws yuav txawv heev yog tias tsis muaj roj. Nws yog ib qho nyuaj rau xav txog tias muaj pes tsawg yam khoom txhua hnub yog tsim los ntawm cov roj. Synthetic fibers uas ua rau cov khaub ncaws, tag nrho cov yas siv nyob rau hauv lub neej txhua hnub thiab kev lag luam, tshuaj, tshuaj pleev ib ce - tag nrho cov no yog tsim los ntawm cov roj. Yuav luag ib nrab ntawm lub zog siv los ntawm noob neej yog tsim los ntawm roj. Nws yog siv los ntawm aircraft xyaw, nrog rau yuav luag tag nrho cov tsheb nyob rau hauv lub ntiaj teb no
Tooj liab phaj, ntawv ci, daim kab xev: ntau lawm, yam ntxwv, daim ntawv thov
Tooj liab yog ib qho ntawm cov hlau nrov tshaj plaws nyob rau hauv lub ntiaj teb niaj hnub no, nws yog siv nyob rau hauv ntau qhov chaw ntawm ntau lawm
Vuas Roj Hmab: ntau lawm los ntawm A txog Z. Daim ntawv teev cov khoom siv thiab kev ua lag luam
Cov vuas roj hmab, uas tuaj yeem tsim tawm ntawm nws tus kheej, yuav tsum tau ua raws li qee yam thev naus laus zis. Cov khoom no tau tshwm sim nyob rau hauv lub tsev muag khoom lag luam kuj tsis ntev los no. Txawm li cas los xij, nws tuaj yeem raug sau tseg tias txawm hais tias qhov kev tsim khoom no tsis dav, nws muaj kev cia siab zoo
Ytterbium fiber ntau laser: ntaus ntawv, kev khiav hauj lwm hauv paus ntsiab lus, lub zog, ntau lawm, daim ntawv thov
Fiber lasers yog compact thiab rugged, taw tes precisely thiab dissipate thermal zog yooj yim. Lawv tuaj hauv ntau hom thiab, muaj ntau yam sib xws nrog lwm hom optical quantum generators, muaj lawv tus kheej zoo
