Aramid yog dab tsi

ARAMID yog dab tsi?

Hauv kev txiav txim siab, aramid yog ahom polyamidethiab yog li lwm qhov ntawm ntau cov hydrocarbon lossis roj av-raws li polymers. Ntawm Wikipedia, lub ntsiab lus yog me ntsis ntau meej, tab sis nyuaj dua:

Cov khoom tshwj xeeb ntawm Aramid / Kevlar ua rau nws cov khoom muaj txiaj ntsig hauv kev ua kis las thiab kev lag luam sab nraum zoov. Nws yog siv hauv hnab looj tes caij ski, thiab lwm yam.

"Aramid fibers are a class of heat-resistant and strong synthetic fibers. […] The name is a portmanteau of 'aromatic polyamide'. The chain molecules in the fibers are highly oriented along the fiber axis. As a result, a higher proportion of the chemical bond contributes more to fiber strength than in many other synthetic fibers. Aramides have a very high melting point (>500 degree)."

Vim li cas thiaj hu ua ib"aromatic polyamide"? Zoo lus nug! Cov pab pawg no (tsawg kawg hauv qhov chaw) tau tso tawm cov ntxhiab tsw (scented) uas feem ntau pom tau tias qab ntxiag. Raws li nthuav raws li qhov no tej zaum yuav yog, peb tsis tshua nyiam qhov tsis hnov ​​​​tsw dua li peb nyob hauv cov khoom siv ua haujlwm.

Tab sis ua ntej peb mus rau qhov nthuav tshaj plaws thiab muaj feem cuam tshuam, ntawm no yog qee cov ntaub ntawv ntxiv txog kev txhim kho cov khoom siv: Hauv nruab nrab xyoo pua, AsmeskasDuPont Grouptau tshawb fawb me ntsis ntawm kev siv aramids. Nyob rau hauv tus txheej txheem, lawv tsim qhov zoo tshaj plaws-paub hom aramidKevlarthiab tau npaj rau kev lag luam siv. Kevlar yog qhov tsuas yog lub npe lag luam uas koj yog ib tus neeg nyiam sab nraum zoov tau hnov ​​​​dua, pom tias qhov no aramid fiber ntau feem ntau siv rau sab nraum zoov thiab roob roob. Qhov tseeb, Kevlar yog tib lub aramid fiber ntau pom nyob rau hauv cheeb tsam no, uas yog vim li cas peb mam li tsom ntsoov rau nws thiab tawm aramid cov khoom, xws li Nomex, Teijinconex, Twaron los yog Technora mus tua tua fighters, tub rog thiab astronauts ...

PRODUCTION

Kev tsim cov aramids yog ntau haiv neeg thiab complex, hais qhov tsawg tshaj plaws. Lawv raug tsim ntau dua lifiberstshaj li cov yeeb yaj kiab. Nyob rau hauv lub ntiaj teb complex ntawm fiber kev tshawb fawb, ib tug sib txawv yog tsim ntawmqis-modulusthiabhigh-modulus fibers, functional zog uas txawv me ntsis ntawm ib leeg.

High modulus fibers yog spun los ntawm cov kua crytalline kua ntawm poly-paraphenylene terephtahalamide nyob rau hauv concentrated sulfuric acid. Tom qab kev kho deg, high-modules fibers yog mechanically stretched kom yield ib tug heev oriented polymer. Qhov "high degree of orientation" ua rau tus qauv huv si. Qhov tseeb geometry tsuas yog cov yam ntxwv ntawm aramid raws li cov xim daj daj, uas coj peb mus rau cov khoom ntawm aramid.

PROPERTIES

Cov neeg tsim khoom siv aramid tsis yog rau lub tsheb kauj vab nkaus xwb tab sis cov ntaub qhwv thiab.

Hauv lawv tus kheej cov lus piav qhia ntawm lawv cov khoom Kevlar, DuPont hais txog tias cov fibers no yog"zoo dua, muaj zog dua thiab nyab xeeb dua"nyob rau sab nraum zoov: "DuPont ™ Kevlar® aramid fiber ntau tso cai rau tib neeg kom Dare Loj dua. Nws yog siv los ua ntau yam khaub ncaws, khoom siv, thiab cov cuab yeej muaj kev nyab xeeb thiab txiav resistant. Nws yog lub teeb yuag, ruaj khov thiab muaj zog heev. Yog lawm, nws yog qhov paub zoo tshaj plaws rau nws siv hauv cov khoom siv phom sij thiab stab-tiv taus lub cev armor, raws li Kevlar® hom aramid fiber txuas ntxiv hloov zuj zus thiab tso cai rau tus phab ej los ua tus phab ej. Tab sis nws kuj tseem nyob ntawm qhov chaw caij ski, txoj kev hloov mus, hauv kev xav tau thaj chaw suab puam, txawm tias qhov txwv sab nraud ntawm qhov chaw."

Kev siv ntau yam yog vim lub fiber ntau (tensile) lub zog, muaj kev cuam tshuam tsis zoo, nruab nrab mus rau qis elongation, zoo vibration-dampening zog thiab kub tsis kam. Es tsis txhob melting, cov fibers pib carbonise ntawm txog 400 degree. Tsis yog cov kuab tshuaj, roj, roj nplua nyeem, dej ntsev, fungi lossis kab mob tuaj yeem ua rau muaj kev phom sij ntau rau aramid fibers. Lawv tsuas yog nkag siab rau qee cov kua qaub thiab alkalis. Hauv lwm lo lus, aramid yog heevtawv.

Thaum nws los txog rau compressive zog, txawm li cas los xij, aramid fabrics yog ntau nruab nrab ntawm pob thiabneeg pluagnyob rau hauv cov nqe lus ntawm UV tsis kam thiab nqus dej (txog 7 feem pua). UV hluav taws xob ua rau cov fiber ntau poob txog li 75 feem pua ​​ntawm nws lub zog. Txawm li cas los xij, qhov no tuaj yeem tiv thaiv tau yooj yim los ntawm UV-absorbing coatings lossis laminates. Feem ntau, aramid tuaj yeem yooj yimua ke nrog lwm cov ntaub, uas txhais tau hais tias nws cov functionality yuav optimized thiab nthuav nyob rau hauv ntau txoj kev.

APPLICATIONS

Cov khoom tshwj xeeb ntawm aramid ua rau nws zoo tagnrho rau ntau yam kev siv, suav nrog kev tsim kho thiab kev lag luam. Kev ua kis las thiab kev lag luam sab nraum zoov nyiam cov khoom siv rau nwstawv, tensile zogthiabhnyav. Aramid fibers yog siv rau cords, paragliding kab, sails, tsheb kauj vab log tsheb thiab lwm yam.

Kevlar cov ntsiab lus hauv textiles ua haujlwm feem ntaukev txhawb zoguas tiv thaiv lub cev thiab ua kom lub neej ntev ntawm cov khaub ncaws. Cov kev txhawb nqa Kevlar yog tshwj xeeb tshaj yog nrov hauv kev caij tsheb kauj vab, maus taus thiab motorsports tsoos tsho nrog rau hauv cov ris tsho hnav sab nraum zoov thiab hnab ev khoom. Kevlar stitching yog siv nyob rau hauv caij ski thiab ntawm ferrata hnab looj tes ib yam nkaus.

Edelrid txawm siv cov khoom siv nce toj iav.

Vim tias cov khoom siv tawv heev, muaj qee qhov nyiajtawvrau nws. Qhov no tuaj yeem yog qhov ntxiv, tab sis muaj qee qhovdownsidesrau nws ib yam nkaus, tshwj xeeb tshaj yog nyob rau sab nraum zoov. Qhov no yog piav qhia los ntawm qhov piv txwv ntawm tus tshiab kujKevlar cords, uas kuj muaj raws li sewn qaum slings nyob rau hauv ntau qhov ntau thiab tsawg. Cov tub ntxhais yog ua los ntawm aramid, thaum lub sheath yog ua los ntawm polyamide, zoo li cov ntaub ntawv "ib txwm" cords thiab hlua. Cov tub ntxhais ntawm aramid yog xim av xim av, yog li nws yooj yim kom paub qhov txawv ntawm cov pa, dazzling dawb polyethylene core ntawm koj li niaj zaus hlua, hlua thiab cov khoom siv webbing.

Lub 5/2014 qhov teeb meem ntawm German-lus DAV Panorama magazine hais txog lub zog siab thiab siab txiav tsis kam ntawm cov khoom raws li qee qhov tseem ceeb.qhov zoo. Ntxiv rau, cov khoom siv tsis yog tsuas yog abrasion thiab kub resistant, tab sis nws kuj boasts lub zog tensile ntau dua li ntawm polyamide cords. Kevlar cords kuj muab lub zog tawg ntau dua li cov khoom siv sib txuas nrog tib txoj kab uas hla.

Raws li ib tugqhov tsis zoo, Panorama magazine tau taw qhia txog qhov ntau dua ntawm cov hlua khi uas pom los ntawm Kevlar cords thaum piv rau cov ntshiab polyamide. Lawv kuj tau taw qhia tias cov khoom siv quasi-static yuav tsum tsis txhob siv rau hauv dynamic belays rau cov thawj coj.

Vim tias nws tsis muaj elasticity (ntau qhov tseeb: qis elongation kom tawg), Kevlar tsis haum rau cov hlua dynamic. Txawm li cas los xij, cov khoom siv tawv tawv tiag tiag tuaj yeem muaj txiaj ntsig zoo rau pob zeb tunnels lossis rappelling tawm ntawm Abalakov teeb tsa.