1 Rababa ƒuƒu tiatia
Plɛti dzoxɔxɔ ɖɔliɖɔli rababa gasket le ɣeyiɣi ma ke me to gas ƒe akpa si le dzoxɔxɔ gã la me, tsi ƒe akpa si wɔa akpa si nye nyaƒoɖeamenu gã, eye hã na kadodo kple ya, dɔwɔwɔ ƒe nɔnɔmewo bia nu geɖe wu. Eyata ele be nusi wotsɔ wɔe la nate ŋu anɔ te ɖe dzoxɔxɔ ƒe nutete nu nyuie ŋutɔ, eye wòate ŋu anɔ te ɖe tsi kple eƒe dzoxɔxɔ nu. Le nɔnɔme mawo me la, ele be nàtia propylene mass fraction si nye 40% ~ 50 % le EPDM me, elabena EPDM ƒe elasticity sia ƒomevie nye nyuitɔ kekeake.
EPDM si ƒe lolome ƒe akpa si lolo le etɔ̃lia ƒe monomer me la ƒe elasticity nyui kple low compression set; ke hã, le alesi woƒoa wo nɔewo nu ƒu ta la, eƒe tenɔnɔŋusẽ kple eƒe didime le gbagbãɣi mebɔbɔna o, eye tsitsi ƒe tsitretsitsi hã medea ŋgɔ o. Tsɔ kpe ɖe eŋu la, EPDM ƒe tsitsi ƒe tsitretsitsi kple ENB abe monomer etɔ̃lia ene nyo wu EPDM si me HD le.
2 Dɔyɔyɔ ƒe ɖoɖo
Zi geɖe la, woate ŋu atsɔ vulcanization ɖoɖo ƒomevi eve awɔ EPDM rababa: peroxide kple sulphur yellow vulcanization. Peroxide vulcanization system ƒe cross-linking bond structure nye CC bond, gake sulphur vulcanization system ƒe cross-linking bond structure nye CS bond. CC ƒe kadodoa te ŋu nɔa te ɖe dzoxɔxɔ nu wu CS kadodoa, eyata wotsɔa peroxide wɔa EPDM rababa si te ŋu nɔa te ɖe dzoxɔxɔ gã nu la vulcanized. Peroxide si wozãna wue nye DCP. Ne DCP ƒe agbɔsɔsɔme dzi ɖe edzi la, wotrɔa rababa si wotsɔ vulcanized wɔe la vivivi tso undersulfurization gbãtɔ, ŋusẽ si mede o kple deformation gã dzi va ɖoa ŋusẽ ƒe dzidziɖedzi kple deformation dzi ɖeɖe kpɔtɔ me; emegbe alesi gbegbe vulcanization la gadzina ɖe edzi, ŋusẽa dzea ɖiɖi gɔme, eye deformation la ɖoa suetɔ kekeake; mlɔeba la, le vulcanizing agent si sɔ gbɔ wu megbe la, molecule kɔsɔkɔsɔa ƒe akpa aɖe dzea kɔsɔkɔsɔa ƒe gbegblẽ gɔme, ŋusẽa yia edzi ɖiɖina, eye vivivi la, eƒe tɔtrɔa dzina ɖe edzi.
3.Filler ƒe agbalẽ
EPDM nye rababa si menye kristalo tɔ o, raw raw ƒe ŋusẽ mede ŋgɔ o. Gake ne wotsɔ nusi doa ŋusẽe kpe ɖe eŋu vɔ la, ŋusẽa dzina ɖe edzi ŋutɔ. Zi geɖe la, nusiwo wotsɔ doa ŋusẽe mekpɔa ŋusẽ boo aɖeke ɖe dzoxɔxɔ ƒe tsitretsitsi dzi o, gake nusi wotsɔ dea eme ƒe agbɔsɔsɔ dzi ɖeɖe kpɔtɔ gakpena ɖe ame ŋu kokoko be rababa la ƒe dzoxɔxɔ te ŋu nɔa te ɖe enu nyuie wu, gake eɖea gazazãwo dzi kpɔtɔna hã.
Ne carbon black ƒe grade le dzidzim ɖe edzi la, compression set dzi ɖena kpɔtɔna, elasticity dzina ɖe edzi, eye ŋusẽa dzi ɖena kpɔtɔna. N990 carbon black ƒe ŋusẽ le sue akpa eye esesẽna be woakpɔ edzi le ewɔwɔ me, eyata womezãnɛ o. To N762 carbon black tiatia me la, woate ŋu akpɔ asixɔxɔ si woɖo ɖe nutete si le bɔbɔe. Be carbon black ƒe kaka nanɔ bɔbɔe eye nàkpɔ dɔwɔwɔ nyuie la, tia plasticizer paraffin ami sue aɖe, si sɔ kple ethylene propylene rababa ŋutɔ.
4. Crosslinking agent
Unsaturated bond aɖeke mele EPDM ƒe kɔsɔkɔsɔ vevitɔ dzi o, togbɔ be woate ŋu azã peroxide vulcanization hã, gake vulcanization ƒe duƒuƒu le blewu, crosslinking ƒe dɔwɔwɔ nyuie le sue. Be woate ŋu ana vulcanization ƒe ɖoɖoa nali ke eye wòawɔe kabakaba la, ehiã be woazã crosslinking agent. TAC/GR si ŋu wowɔ atike ɖo la nyo wu na kaka kple kpekpeme.
Esi TAC/GR ƒe agbɔsɔsɔ dzi ɖe edzi la, tensile strength, elongation at break kple compression permanent deformation of vulcanized rubber dzi ɖe kpɔtɔ, eye MH ƒe asixɔxɔ si le tensile stress si nɔa anyi ɖaa ŋu dzi ɖe edzi. Woate ŋu akpɔe be wowɔ vulcanized rubber ƒe crosslinking density nyo ɖe edzi, mɔ̃ɖaŋununya ƒe nɔnɔmewo dzi ɖe kpɔtɔ, gake elasticity la va lolo ɖe edzi. Le ɣeyiɣi ma ke me la, ML ƒe asixɔxɔ dzi ɖe kpɔtɔ, si fia be Mooney ƒe ʋeʋẽ dzi ɖe kpɔtɔ, rababa la ƒe tsinyenye dzi ɖe edzi, eye eŋudɔwɔwɔ le bɔbɔe; ts1 koŋ metrɔ o, eye woɖe t 90 ƒe asixɔxɔ dzi kpɔtɔ, eye edze ƒã be vulcanization ƒe duƒuƒu nyo ɖe edzi. Tsitsi ƒe dɔwɔwɔ menyo o wu le TAC/GR ƒe 1.5phr me. Esia ate ŋu atso cross-linking aid ƒe anyinɔnɔ gbɔ, ana peroxide vulcanization ƒe ɖoɖoa nawɔ dɔ, ana vulcanization ƒe ɣeyiɣia nanɔ kpuie, aɖe rababa molecule chain ƒe gbagbã kple disproportionation ƒe mɔnukpɔkpɔ dzi akpɔtɔ le dzoxɔxɔ gã me. Ne agbɔsɔsɔa sɔ gbɔ akpa la, enaa rababa la ƒe tsitsi ƒe cross-linking dzina ɖe edzi eye wòɖea EPDM ƒe dzoxɔxɔ ƒe tsitretsitsi dzi kpɔtɔna. Ne wotsɔe sɔ kple wo nɔewo vɔ la, compression permanent deformation nyo wu le 2phr, eye wometsɔa dzoxɔxɔ ƒe tsitretsitsi saa vɔe boo o, eyata wozãa TAC/GR le 2phr.
5.Nu si tsia dzoxɔxɔ nu
Woate ŋu azã EPDM ɣeyiɣi didi aɖe le dzoxɔxɔ si nye 150 °C me , gake ne ewu 150 °C la , moleculeawo dzea tsitsi gɔme vivivi, eye ne dzoxɔxɔa nye 180 °C la , rababa ƒe molecule ƒe kɔsɔkɔsɔa agblẽ vivivi. Be woate ŋu ana eƒe dɔwɔwɔ nanyo ɖe edzi le dzoxɔxɔ gã me la, ele be woazã ametakpɔnu siwo wotsɔ kpena ɖe eŋu. Le tsi-yaƒoƒo ƒe nyadzɔdzɔgblɔmɔnuwo gome la, woate ŋu azã antioxidant RD, si te ŋu nɔa te ɖe dzoxɔxɔ gã nu gake mekpɔa ŋusẽ ɖe vulcanization dzi bɔbɔe o. Gakpe ɖe eŋu la, woate ŋu azã 0.5phr antioxidant D atsɔ ado ŋusẽ ŋutete si le esi be wòatsi tre ɖe oxygen ŋu le ya me eye wòana flexural fatigue resistance nanyo ɖe edzi. RD/anti-butyl ƒe xexlẽme=1.8/0.5.
Nyanuwuwuw
Tsi ƒe dzoxɔxɔ gã-tsi ƒe dzoxɔxɔ-tsitretsitsi gã elasticity EPDM rababa ƒe ŋgɔyiyi, nusi ŋu wotsia dzi ɖoe nye be woado go mɔ̃ɖaŋununya ƒe nɔnɔmewo le gɔmeɖoanyi si nye be woadzi tsitsi ƒe tsitretsitsi ɖe edzi eye woaɖe nutete tegbee deformation ƒe asixɔxɔ dzi akpɔtɔ.
( 1) Wotia EPDM rababa ƒuƒu la kple 40% ~ 50% ƒe propylene kple medium mass fraction of ENB abe monomer etɔ̃lia ene.
( 2) Vulcanization ɖoɖoa xɔa DCP/ TAC, si kpena ɖe ame ŋu be crosslinking ƒe dɔwɔwɔ nyuie, tsitsi ƒe tsitretsitsi kple dɔwɔwɔ ƒe dɔwɔwɔ nanyo ɖe edzi.
( 3) Zã high elasticity carbon black N762 alesi nàte ŋui, si ate ŋu akpe ɖe ŋuwò nàna tsitretsitsi ɖe nyadzɔdzɔgblɔmɔnuwo ƒe gege ɖe eme kple tsitsi ƒe dɔwɔwɔ ŋu nanyo ɖe edzi, eye ate ŋu aɖe gazazã dzi akpɔtɔ.
( 4) Woaxɔ ametakpɔnu si nye antioxidant RD/antioxidant D, eye antioxidant RD si ƒe dzoxɔxɔ loloe nye vevitɔ, eye antioxidant D si te ŋu nɔa te ɖe ɖeɖiteameŋu si le flexural nu eye wòte ŋu nɔa te ɖe ozone nu abe kpeɖeŋutɔ ene.
( 5) Ewɔwɔ ƒe ɖoɖoa xɔa dzoxɔxɔ gã ƒe evelia ƒe vulcanization be woadzi vulcanization ƒe agbɔsɔsɔme ɖe edzi.
(6) Edze ƒã be EPDM ƒe dɔwɔwɔ le tsi si xɔ dzo akpa kple tsi ƒe dzoxɔxɔ me nyo wu esi le ya me (dzoxɔxɔ ɖeka). Gake togbɔ be ele alea hã la, dzoxɔxɔ si wòzãna ɣeyiɣi didi la mewu 150 °C kokoko o ; impact temperature si nye 165 °C sɔ, esi kɔkɔ wu mate ŋu agbɔ 180 °C ŋu o.
