The embrittlement wa silikoni mphira pa 250 digiri si "yachibadwa" mawonetseredwe ake, koma chifukwa cha umagwirira ake ukalamba pansi pa mikhalidwe yeniyeni.
Nthawi zambiri, mphira wa sililicone umadziwika chifukwa chosamva kutentha kwake, ndipo kutentha kwake kumakhala kotalika-kuyambira -60 digirii kufika pa 200-230 digirii . Kutentha kukakwera mpaka kumtunda wa digirii 250 kapena kupitilira apo, njira zingapo zokalamba zimachulukira, ndipo pamapeto pake zimatsogolera ku embrittlement. Choyambitsa chachikulu cha embrittlement chagona pakuwonongeka kwamankhwala kosasinthika kwa unyolo waukulu ndi magulu am'mbali a polima ya mphira ya silikoni. Pano pali njira zingapo zomwe zimatsogolera ku embrittlement
1. Njira yamagulu amtundu wa oxidation (makina akuluakulu): Mtundu wodziwika kwambiri wa mphira wa silikoni ndi rabara ya silikoni ya methyl vinyl. Pakutentha kwambiri, mpweya wa mumlengalenga umalimbana ndi magulu a methyl (-CH₃) pamaketani am'mbali a ma polima. Chemical reaction: Gulu la methyl limapangidwa oxidized, choyamba kupanga gulu la hydroxyl (-OH), lomwe limatha kuwoloka-kulumikizana kapena kupanga ma oxide ena. Njirayi imapanga mfundo zowonjezera zowonjezera (oxidative crosslinking) pakati pa maunyolo a maselo.
Zotsatira zake: Pamene kuchuluka kwa ma crosslinking ena kumachulukirachulukira, ma polima network amathina kwambiri komanso olimba. Zinthuzo zimataya mphamvu, zimakhala zouma, ndipo pamapeto pake zimathyoka ngati zili ndi nkhawa zazing'ono. Mutha kulingalira ukonde wophera nsomba. Node zake zikachuluka komanso zokhuthala kwambiri, zimataya kusinthasintha kwake ndipo zimasweka mosavuta zikakoka.
2.Main chain depolymerization (" unwinding "reaction) process: Pa kutentha kokwanira, siloxane main chain (-Si-O{3}}) imatha kusweka. Chemical reaction: The main unyolo imasweka, kupanga oligomers cyclic (monga D3, D4, etc.) ndi mamolekyu ena ang'onoang'ono.
Zotsatira zake: Kutalika kwa unyolo wa polima kumafupikitsa ndipo kulemera kwa maselo kumachepa. Izi zimabweretsa mwachindunji kuchepetsa mphamvu zamakina zakuthupi. Unyolo ukakhala waufupi kwambiri, zinthuzo sizingathe kupirira kupsinjika komanso zimakhala zolimba. Njirayi imatha kuchitika mukakhalapo komanso mulibe mpweya, koma imakhala yofunika kwambiri pakatentha kwambiri.
3. Kuwonongeka kwa zinthu zomwe zimasokonekera komanso zopangira mapulasitiki: Popanga mphira wa silikoni, ma siloxane ocheperako-mamolekyulu-amatha kukhalabe, kapena kuwonjezera zina kuti ziwonjezeke. Pakatentha-kwanthawi yayitali, zinthu zotsika-zolemera-zolemera zimasintha pang'onopang'ono kapena kutuluka.
Zotsatira zake: Pamlingo wakutiwakuti, zinthuzi zimagwira ntchito yopaka mafuta mkati ndi kupanga pulasitiki. Kutayika kwawo kumapangitsa kuti zinthuzo zikhale zolimba, kufota komanso kukhala zolimba.
4.Thermal njinga ndi kutopa kutopa
ndondomeko: Ngati pamakhala kuzizira komanso kutentha kwanthawi zonse pakugwiritsa ntchito, mphira wa silikoni umakula ndikukhazikika.
Zotsatira: Kupsinjika kwanthawi ndi nthawi kungayambitse ma microcracks mkati mwazinthu. Pansi pa kutentha kwapamwamba, ma microcracks awa amafulumizitsa kukulitsa ndi kulumikizana kwawo, kenako ndikupangitsa kuti zinthuzo ziwonongeke.