Ƙirƙirar roba na silicone a digiri 250 ba bayyanar "al'ada" ba ce, amma sakamakon tsarin tsufa a ƙarƙashin takamaiman yanayi.
Gabaɗaya, robar silicone sananne ne don juriyar zafi, tare da dogon lokaci{0} yanayin zafi na sabis wanda yawanci ke jere daga digiri -60 zuwa digiri 200-230. Lokacin da zafin jiki ya tashi zuwa babba na digiri na 250 ko mafi girma, yawancin manyan matakan tsufa zasu haɓaka, ƙarshe yana haifar da haɓakawa. Babban dalilin embrittlement ya ta'allaka ne a cikin lalacewar sinadarai da ba za a iya jurewa ba na babban sarkar da ƙungiyoyin gefe na siliki roba polymer. Wadannan su ne manyan hanyoyin dabaru da yawa waɗanda ke haifar da ɓarna
1. Side kungiyar hadawan abu da iskar shaka (babban inji) tsari: Mafi na kowa irin silicone roba ne methyl vinyl silicone roba. A yanayin zafi mai yawa, iskar oxygen a cikin iska za ta kai hari ga ƙungiyoyin methyl ({2}}CH₃) akan sassan sassan polymers. Halin sinadarai: Ƙungiyar methyl ta kasance oxidized, da farko ta samar da ƙungiyar hydroxyl (-OH), wanda zai iya haye{5}} mahada ko samar da wasu oxides. Wannan tsari yana samar da ƙarin madaidaitan madaidaitan ma'auni (madaidaicin oxidative crosslinking) tsakanin sassan kwayoyin halitta.
Sakamako: Yayin da adadin ƙarin wuraren haɗin kai ke ci gaba da ƙaruwa, cibiyar sadarwar polymer ta zama mai girma da ƙarfi. Kayan yana rasa ƙarfinsa, ya zama mai tauri, kuma a ƙarshe yana fuskantar karaya lokacin da aka fuskanci ƙananan damuwa. Kuna iya tunanin gidan kamun kifi. Lokacin da noyoyinsa suka yi yawa kuma suka yi yawa, yana rasa sassauƙarsa kuma yana karyewa cikin sauƙi idan an ja shi.
2.Main sarkar depolymerization (" unwinding "reaction): A isasshe babban zafin jiki, babban sarkar siloxane (-Si-O-) kanta na iya karye. Maganin sinadaran: Babban sarkar karya, samar da oligomers na cyclic (kamar D3, D4, da sauransu) da sauran ƙananan ƙwayoyin cuta.
Sakamakon: Tsawon sarkar polymer yana raguwa kuma nauyin kwayoyin yana raguwa. Wannan kai tsaye yana haifar da raguwa a cikin ƙarfin injiniyoyi na kayan. Lokacin da sarkar ta zama gajere sosai, kayan ba zai iya ɗaukar damuwa yadda ya kamata ba kuma zai zama mara ƙarfi. Wannan tsari na iya faruwa a duka kasancewa da rashin iskar oxygen, amma yana da mahimmanci musamman a yanayin zafi sosai.
3. Tsarin hasara na sinadarai masu lalacewa da masu robobi: Yayin samar da robar silicone, wasu ƙananan siloxanes masu nauyi - na iya zama, ko kuma ana iya ƙara wasu abubuwan ƙari don haɓaka aiki. Karkashin yanayin zafi mai tsawo{4}}, waɗannan ƙananan abubuwa{5}}wayoyin nauyi{6} za su canza a hankali ko ƙaura.
Sakamakon: Zuwa wani ɗan lokaci, waɗannan abubuwa suna taka rawa a cikin lubrication na ciki da yin filastik. Rashin su zai sa kayan suyi taurare, raguwa kuma su zama masu rauni.
4.Thermal hawan keke da damuwa gajiya
tsari: Idan akwai m sanyi da zafi hawan keke a cikin aikace-aikace yanayin, silicone roba zai kullum fadada da kwangila.
Sakamakon: Wannan damuwa na lokaci-lokaci na iya haifar da ƙananan ƙwayoyin cuta a cikin kayan. A karkashin catalysis na babban yanayin zafi, waɗannan microcracks za su hanzarta haɓakawa da haɗin gwiwa, a ƙarshe yana haifar da fashewar kayan macroscopic.