Dab tsi yog roj hmab EPDM

Roj hmab EPDM (ethylene propylene diene monomer roj hmab)[1][2][3]yog ib hom ntawmhluavtaws roj hmabuas yog siv rau hauv ntau daim ntawv thov.

EPDM yog M-Class roj hmab hauv qabASTMtus qauv D-1418; theMclass compriseselastomersmuaj asaturatedsaw hlau ntawmpolyethylenehom (tus M deriving los ntawm ntau cov lo lus tseeb polymethylene). EPDM yog tsim los ntawmethylene,roj ntsha, thiab adienecomonomer uas ua rau crosslinking ntawm leej faj vulcanisation. Cov kwv tij yav dhau los ntawm EPDM yog EPR, roj hmab ethylene-propylene, uas tsis muaj cov roj ntsha diene thiab tsuas yog crosslinked siv cov kev qhia dhau los xws li peroxides.[4]Dienes siv hauv kev tsim cov khoom ntawm EPDM rubbers yogethylidene norbornene(ENB),dicyclopentadiene(DCPD), thiabvinyl norbornene(VNB).

EPDM muab tau los ntawm polyethylene mus rau qhov uas 45-85 wt% ntawm propylene tau copolymerised los txo cov kev tsim ntawm cov polyethylene crystallinity raug. EPDM yog cov khoom siv semi-crystalline nrog cov ethylene-hom siv lead ua qauv ntawm cov qib siab ethylene, los ua qhov tseem ceebamorphousntawm cov ntsiab lus ethylene uas ze rau 50 wt%.

Cov pob zeb txhuam nrog cov nplais roj ntshiab polymer pob txha caj qaum, xws li EPDM, muaj kev tiv thaiv zoo dua rau kev ua kom sov, lub teeb thiab ozone dua li cov roj av tsis huv xws lintuj roj hmab,SBRlossispolychloroprene(Neoprene). Xws li, EPDM tuaj yeem tsim tau los tiv thaiv qhov kub thiab txias li 150 ° C, thiab, tsim qauv tsim nyog, tuaj yeem siv sab nraud tau ntau xyoo lossis xyoo lawm yam tsis muaj kev cuam tshuam. EPDM muaj cov khoom kub tsis tshua zoo, nrog cov khoom ntog ua rau kub qis li -40 ° C nyob ntawm qib thiab cov qauv.

Raws li nrog feem ntau rubbers, EPDM yog ib txwm siv compounded nrog sau rau hauv xws licarbon dubthiab calcium carbonate, nrog plasticisers xws li cov roj paraffinic, thiab muaj cov khoom muaj txiaj ntsig zoo nkauj tsuas yog thaumntoo khaub ligCov. Crosslinking feem ntau yuav siv qhov chaw ntawmlus mosnrog leej faj, tab sis kuj tseem ua tiav nrogKev cog lus(rau kev ua kom sov zoo dua) lossis nrog phenolic resins. Muaj hluav taws xob muaj zog xws li los ntawmhluav taws xob kab teebyog qee zaum siv rau kev tsim foams thiab xaim thiab cable.