1 Ukukhethwa kwerabha eluhlaza
I-Plate heat exchanger rubber gasket ngasikhathi sinye ngasohlangothini lwegesi lokushisa okuphezulu, uhlangothi lwamanzi lwendima yokucindezela okukhulu, futhi luphinde lube nokuxhumana nomoya, izimo zokusebenza zidinga kakhulu. Ngakho-ke, impahla kufanele ibe yinhle kakhulu ukumelana nokushisa kokucindezela, futhi ingakwazi ukumelana namanzi kanye nomusi wawo. Ezimweni ezinjalo, kufanele ukhethe ingxenyenamba ye-propylene mass of 40% ~ 50 % ye-EPDM, ngoba lolu hlobo lwe-EPDM elasticity lungcono kakhulu.
I-EPDM enengxenye enkulu ye-monomer yesithathu ine-elasticity enhle nesethi yokucindezela okuphansi; nokho, ngenxa yezinga eliphezulu lokuxhumanisa, amandla okuqina kanye nobude ngesikhathi sekhefu aphansi, futhi ukumelana nokuguga nakho kubi. Ngaphezu kwalokho, ukumelana nokuguga kwe-EPDM ene-ENB njenge-monomer yesithathu kungcono kunaleyo ye-EPDM ene-HD.
2 Uhlelo lokwelapha
Ngokuvamile, irabha ye-EPDM ingavuthwa ngezinhlobo ezimbili zezinhlelo ze-vulcanization: i-peroxide kanye ne-sulphur yellow vulcanization. Isakhiwo sebhondi esixhumanisa esiphambanweni sohlelo lwe-peroxide vulcanization siyisibopho se-CC, kuyilapho ukwakheka kwebhondi exhumanisa okuphambanayo yohlelo lwe-sulfur vulcanization kuyisibopho se-CS. Ibhondi ye-CC izinze kakhulu ngokufudumeza kunebhondi ye-CS, ngakho-ke irabha ye-EPDM emelana nezinga lokushisa eliphezulu ifakwa i-peroxide. I-peroxide esetshenziswa kakhulu yi-DCP. Ngokukhuphuka komthamo we-DCP, irabha ene-vulcanized iguqulwa kancane kancane isuka ku-undersulfurization yokuqala, amandla aphansi kanye nokuguqulwa okukhulu kuya ekwandeni kwamandla nokuncipha kokuguqulwa; khona-ke izinga le-vulcanization liyanda, amandla aqala ukwehla, futhi ukuguqulwa kufinyelela ubuncane; ekugcineni, ngemva kokudlulela kwe-ejenti ye-vulcanizing, ingxenye yeketanga lamangqamuzana iqala ukugqashula ukuwohloka kweketango, amandla aqhubeka ehla, futhi ukuguqulwa kwanda kancane kancane.
3.Ukugcwalisa
I-EPDM ingeyerabha engeyona i-crystalline, amandla enjoloba eluhlaza awaphezulu. Kodwa ngemva kokwengeza i-reinforcing filler, amandla anda kakhulu. Ukuqinisa ama-filler ngokuvamile akunawo umthelela omncane ekuphikiseni ukushisa, kodwa ukwandisa inani lokugcwalisa kusasiza ukuthuthukisa ukumelana nokushisa kwerabha, kodwa futhi kunciphisa izindleko.
Njengoba izinga le-carbon black likhuphuka, isethi yokucindezela iyancipha, ukunwebeka kuyanda, futhi amandla ayancipha. Amandla e-N990 carbon black aphansi kakhulu futhi kunzima ukuwalawula ekukhiqizeni, ngakho-ke awasetshenziswa. Ngokukhetha i-N762 carbon black, inani eliphansi lesethi yokucindezelwa lingatholakala. Ukuze kube lula ukuhlakazwa kwe-carbon black futhi uthole ukusebenza okuhle kokucubungula, khetha inani elincane lamafutha e-plasticizer parafini, ahambisana kakhulu ne-ethylene propylene rubber.
4. I-Crosslinking agent
Ayikho ibhondi engagcwalisiwe ochungechungeni oluyinhloko lwe-EPDM, nakuba i-peroxide vulcanization ingasetshenziswa, kodwa isivinini se-vulcanization sihamba kancane, ukusebenza kahle kwe-crosslinking kuphansi. Ukuze uzinzise futhi usheshise inqubo ye-vulcanization, kuyadingeka ukusebenzisa i-agent yokuxhumanisa. I-TAC/GR ephathwayo ingcono ekuhlakazeni nasekukaleni.
Ngokukhula kwenani le-TAC/GR, amandla okuqina, ubude ngesikhathi sekhefu kanye nokucindezelwa ukuguqulwa unomphela kwenjoloba ecindezelwe kwehla, kanye nenani le-MH lokucindezeleka okuqinile okuqhubekayo lenyuka. Kungabonakala ukuthi ukuminyana okuxhumanisayo kwenjoloba eyenziwe nge-vulcanized kwathuthukiswa, izakhiwo zemishini zehla, kodwa ukunwebeka kwaba kukhulu. Ngesikhathi esifanayo, inani le-ML lehla, okubonisa ukuthi i- Mooney viscosity yehla, i-fluidity yerabha yathuthukiswa, futhi kulula ukucutshungulwa; I-ts1 empeleni yayingashintshiwe, futhi inani le-t 90 lafushaniswa, futhi isivinini se-vulcanization ngokusobala sathuthukiswa. Ukusebenza kokuguga kwaba kubi kakhulu ku-1.5phr we-TAC/GR. Lokhu kungase kube ngenxa yokuba khona kosizo lokuxhumanisa, sebenzisa inqubo ye-peroxide vulcanization, unciphise isikhathi se-vulcanization, unciphise amathuba okuphuka kweketango lamangqamuzana enjoloba kanye nokungalingani ekushiseni okuphezulu. Uma inani likhulu kakhulu, lithuthukisa ukuguga okuxhumanisa irabha futhi linciphise ukumelana nokushisa kwe-EPDM. Ngemuva kokuqhathanisa, ukuguqulwa okuhlala njalo kokucindezela kungcono ku-2phr, futhi ukumelana nokushisa akunikelwanga kakhulu, ngakho-ke i-TAC / GR isetshenziswa ku-2phr.
5.I-Antioxidant
I-EPDM ingasetshenziswa isikhathi eside ku-150 ℃ , kodwa ngaphezu kuka-150 ℃ , ama-molecule aqala ukuguga kancane kancane, futhi ku-180 ℃ , uchungechunge lwe-molecular yenjoloba luzobola kancane kancane. Ukuze uqhubeke uthuthukisa ukusebenza kwayo emazingeni okushisa aphezulu, izithasiselo zokuzivikela kufanele zisetshenziswe. Endabeni yemidiya yomusi wamanzi, i-antioxidant RD ingasetshenziswa, ephikisana nokushisa okuphezulu kodwa ayithinti kalula i-vulcanization. Ngaphezu kwalokho, i-0.5phr antioxidant D ingasetshenziselwa ukuqinisa amandla okumelana nomoya-mpilo emoyeni futhi ithuthukise ukumelana nokukhathala okuguquguqukayo. Isilinganiso se-RD/anti-butyl=1.8/0.5.
Isiphetho
Ukuthuthukiswa kwerabha ye-EPDM yamanzi asezingeni lokushisa ephezulu engavimbeli umhwamuko, kugxilwe kuyo ukuhlangabezana nezakhiwo zemishini ngaphansi kwesisekelo sokukhulisa ukumelana nokuguga nokunciphisa inani lokuguga lokucindezelwa unomphela.
( 1) Irabha ye-EPDM eluhlaza ikhethwa nge-40% ~ 50% ye-propylene kanye nengxenye ye-medium mass ye-ENB njenge-monomer yesithathu.
( 2) Uhlelo lwe-vulcanization lwamukela i-DCP/TAC, esiza ukuthuthukisa ukusebenza kahle kwe-crosslinking, ukumelana nokuguga nokusebenza kwenqubo.
( 3) Sebenzisa i-high elasticity carbon black N762 ngangokunokwenzeka, engasiza ekuthuthukiseni ukumelana nokuqina kwemidiya nokusebenza kokuguga, futhi kunganciphisa izindleko.
( 4) Yamukela uhlelo lokuvikela lwe-antioxidant RD/antioxidant D, ene-high-temperature antioxidant RD njengeyona eyinhloko, kanye ne-flexural-resistant-resistant and ozone-resistant antioxidant D njengensiza.
( 5) Inqubo yokukhiqiza isebenzisa izinga lokushisa eliphakeme lesibili le-vulcanization ukuze kwandiswe izinga lokuvuvukala.
(6) Ukusebenza kwe-EPDM emanzini ashisa kakhulu kanye nomhwamuko wamanzi ngokusobala kungcono kunalokho okusemoyeni (ukushisa okufanayo). Kodwa noma kunjalo, ukusetshenziswa kwayo isikhathi eside kwezinga lokushisa kusengaphezu kuka-150 ℃ ; izinga lokushisa lomthelela lika-165 ℃ lifanelekile, eliphakeme kakhulu alikwazi ukudlula i-180 ℃.
