Mukudziwa chiyani za EPDM?

Chiyambi cha EPDM

EPDM ndi terpolymer ya ethylene, propylene ndi non-conjugated dienes, yomwe inayamba kupanga malonda mu 1963. Kugwiritsidwa ntchito kwapachaka kwa dziko lapansi ndi matani 800000. Chikhalidwe chachikulu cha EPDM ndi kukana kwake kwa okosijeni kwapamwamba, kukana kwa ozoni ndi kukana kwa dzimbiri. Popeza EPDM ndi ya banja la polyolefin (PO), ili ndi zinthu zabwino kwambiri zowononga. Pakati pa ma rubbers onse, EPDM ili ndi mphamvu yokoka yotsika kwambiri ndipo imatha kuyamwa zodzaza ndi mafuta ambiri popanda kukhudza katundu. Choncho, imatha kupanga mankhwala opangira mphira otsika mtengo.

Kachitidwe

• Kutsika kochepa komanso kudzaza kwakukulu

Ethylene-propylene rabara ili ndi kachulukidwe kakang'ono ka 0.87. Kuonjezera apo, mafuta ambiri amatha kudzazidwa ndi kudzaza wothandizira akhoza kuwonjezeredwa, zomwe zingathe kuchepetsa mtengo wamankhwala amphira, kupanga zofooka za mtengo wapamwamba wa mphira wa EPDM yaiwisi yaiwisi, ndi EPDM yokhala ndi mtengo wapamwamba wa Mooney, mphamvu yakuthupi ndi yamakina pambuyo pa kudzazidwa kwakukulu sikuchepetsedwa kwambiri.

• Kukana kukalamba

Rabara ya ethylene-propylene imakhala ndi kukana kwanyengo kwabwino kwambiri, kukana kwa ozoni, kukana kutentha, kukana kwa asidi ndi alkali, kukana kwa nthunzi wamadzi, kukhazikika kwamtundu, mphamvu zamagetsi, kudzaza mafuta komanso kutentha kwanthawi zonse.Zopangira mphira wa ethylene-propylene angagwiritsidwe ntchito kwa nthawi yaitali pa 120 ℃, ndipo angagwiritsidwe ntchito mongoyembekezera kapena intermittently pa 150 - 200 ℃. Kutentha kogwiritsa ntchito kumatha kukulitsidwa powonjezera antioxidant yoyenera. EPDM crosslinked peroxide ingagwiritsidwe ntchito pansi pa zovuta. Pansi pa ozoni ndende ya 50 phm ndi kutambasula kwa 30%, EPDM sichitha kusweka kwa maola oposa 150.

• Kukana dzimbiri

Chifukwa chosowa polarity ndi otsika unsaturation mphira ethylene-propylene, ali bwino kukana zosiyanasiyana polar mankhwala monga mowa, asidi, alkali, okosijeni, refrigerant, detergent, nyama ndi masamba mafuta, ketone ndi mafuta; Komabe, ili ndi kusakhazikika bwino mu zosungunulira za aliphatic ndi zonunkhira (monga mafuta, benzene, etc.) ndi mafuta amchere. Pansi pa zochita za nthawi yayitali za asidi wambiri, ntchitoyo idzachepanso.

• Kukana kwa nthunzi wamadzi

EPDM ili ndi kukana kwa nthunzi wamadzi kwabwino kwambiri ndipo ikuyerekezeredwa kuti ndiyoposa kukana kwake kutentha. Mu nthunzi yotentha kwambiri ya 230 ℃, palibe kusintha kwa mawonekedwe pambuyo pa maola pafupifupi 100. Komabe, mumikhalidwe yomweyi, mphira wa fluorine, mphira wa silicon, labala wa fluorosilicone, labala la butyl, labala la nitrile ndi mphira wachilengedwe zidawonongeka mowonekera pakanthawi kochepa.

• Kukana madzi otentha

Ethylene-propylene rabara imakhalanso yabwino kukana madzi otentha kwambiri, koma imagwirizana kwambiri ndi machitidwe onse ochiritsa. The makina katundu wa mphira ethylene-propylene ndi morpholine disulfide ndi TMTD monga machiritso dongosolo anasintha pang'ono ataviika mu 125 ℃ superheated madzi kwa miyezi 15, ndipo voliyumu kukulitsa mlingo anali 0.3% yokha.

• Kuchita kwamagetsi

Rabara ya ethylene-propylene imakhala ndi magetsi abwino kwambiri komanso kukana kwa corona, ndipo mphamvu zake zamagetsi ndizopambana kapena kuyandikira za rabara ya styrene-butadiene, chlorosulfonated polyethylene, polyethylene ndi polyethylene yolumikizana ndi mtanda.

• Kusangalala

Chifukwa palibe polar substituent mu kapangidwe ka maselo a mphira wa ethylene-propylene ndipo mphamvu yolumikizana ndi ma cell ndi yotsika, unyolo wa mamolekyulu ukhoza kukhalabe wosinthika mosiyanasiyana, wachiwiri kokha ku mphira wachilengedwe ndi mphira wa cis-polybutadiene, ndipo utha kukhalabe pa kutentha kochepa.

• Kumamatira

Chifukwa chosowa magulu yogwira mu dongosolo maselo amphira wa ethylene-propylene, mphamvu yolumikizana yochepa, ndi kupopera mosavuta kwa chisanu kwa mphira, kudzimangiriza ndi kumamatira pamodzi ndizosauka kwambiri.

Ubwino

• Ili ndi chiŵerengero chapamwamba cha ntchito-mtengo. Kuchuluka kwa mphira yaiwisi ndi 0.86 ~ 0.90g / cm3 yokha, yomwe ndi mphira wodziwika kwambiri wokhala ndi mphira wopepuka kwambiri wa rabara yaiwisi; Ikhozanso kudzazidwa mochuluka kuti muchepetse mtengo wa rabara.
• Kukana kukalamba kwabwino, kukana kwanyengo, kukana kwa ozoni, kukana kwa dzuwa, kukana kutentha, kukana madzi, kukana kwa nthunzi wamadzi, kukana kwa UV, kukana kwa radiation ndi zinthu zina zokalamba. Mukagwiritsidwa ntchito ndi mphira wa diene wopanda unsaturated monga NR, SBR, BR, NBR, ndi CR, EPDM imatha kugwira ntchito ya polymer antioxidant kapena antioxidant.
• Kukana mankhwala abwino, asidi, alkali, detergent, nyama ndi masamba mafuta, mowa, ketone, etc; Kukana kwabwino kwa madzi, madzi otentha kwambiri ndi nthunzi; Kukana mafuta a polar.
• Kuchita bwino kwambiri kwa kutchinjiriza, kuchuluka kwa resistivity 1016Q · cm, voteji yowonongeka 30-40MV/m, dielectric constant (1kHz, 20 ℃) ​​2.27.
• Imagwiritsidwa ntchito pamitundu yosiyanasiyana ya kutentha, yokhala ndi kutentha kosachepera - 40 ~ 60 ℃, ndipo ingagwiritsidwe ntchito pa 130 ℃ kwa nthawi yayitali.