Ba kamar thermoplastics na thermoplastics ba, ana amfani da ealastomers a kan yada yanayi mai yawa kuma yana da muhimmanci a saman yanayin yanayin zafin su (tg). Amfanin elastomers akan thermoplastics ikon su na murmurewa kusan gaba daya daga jihar tenesility), letging da low elulus kaddarorin. Lokacin da ana amfani da elastomers a ƙasa zazzabi dakin, suna nuna karuwa cikin tauri, karuwa a cikin modulus, da raguwar a cikin elasticity. Lokacin da ana amfani da elastomers a ƙasa zazzabi dakin, akwai hali na wahala don ƙaru, modulus don ƙara, elasticity don rage (low miliyoyin da karuwa don ƙaruwa. Ya danganta da matsalar tare da elastomer, abubuwa biyu na iya faruwa a lokaci guda - gilashi mai wahala - cr, ep, nr wasu misalai ne na elstomers waɗanda ke nuna crastallization.
1. Overview na ƙarancin gwajin zafin jiki
Kabilanci, matsanancin rashin tsoro na har abada, abin tunawa, da hardening da kuma bugun zuciya an yi amfani da su shekaru da yawa domin rarrabe allolin polymer a ƙananan yanayin zafi. Ja mai ban sha'awa damuwa yana da sababbi kuma yana mai da hankali kan tantance karfin kayan abu a tsawon lokaci a karkashin yanayi daban-daban.
2. Yawan zafin jiki
Astm D 2137 yana bayyana yawan zafin jiki a matsayin mafi ƙarancin zafin jiki wanda ya fi ƙarancin roba mara ƙarfi ba zai nuna rauni ba ko lalata ƙarƙashin yanayin tasirin da aka ƙayyade. An shirya samfuran samfuran roba guda biyar na sifar da aka ƙaddara biyar, sanya shi a cikin wani ɗaki ko matsakaici mai ruwa, an gindaya shi zuwa zazzabi na 2.0 ± 0M 0.2M 0.2M 0 s. An cire samfuran kuma an cire samfuran kuma an hore shi zuwa tasirin ko gwajin gwaji. An cire samfurin kuma an gwada don tasiri ko karaya, duk ba tare da lalacewa ba. An maimaita gwajin har zuwa yawan zafin jiki - mafi ƙarancin zafin jiki wanda ba a samo karaya yana da kusanci 1 ° C ba.
3. Low zazzabi ta kashe zazzabi da ƙarancin zafin jiki
Tsarin gwajin don ƙarancin zafin jiki wanda yake kusa yana da kusanci da wannan don tsarin matsakaicai da aka tsara, kamar yadda kuma hanyoyin injin ke sarrafawa, kamar yadda ƙimar ruwa, kuma darajar injiniya tana sarrafawa, kamar yadda ƙimar tana cikin ± 1 ° C na mitar zazzabi. Bayan murmurewa daga tsira, samfurin da aka sanya a farkon let zazzabi kuma an canza shi zuwa diamita na 29 Mm da kauri na 12.5 mm. Tsarin matsakaiciyar zazzabi na zazzabi shine hanya madaidaiciya don ƙyanaci aikace-aikace na fili a cikin tambaya. Haramtaccen daddare dan iska shine hanyar kai tsaye kuma za a tattauna daga baya. Harshen zafin jiki mai yawa kuma ana ƙaddara shi ta amfani da ƙirar m turawa (29m x 12.5mm), amma sake gwada shi a cikin yanayin matsakaiciya, sannan kuma a cikin zafin jiki da aka saita. Hardening da ƙaramin ƙarancin zazzabi suna kwarewa kai tsaye ta hanyar sanyaya, amma kuma ta hanyar kunnawa a kan ƙananan yanayin sarkar polymer, sannan kuma sarkar kwayar cuta ta daskarewa kafin a sake amfani da shi).
4. Gehman low zazzabi
Astm d 1053 ya bayyana ƙarancin zafin jiki kamar haka: Jerin ƙirar polymer na roba ana haɗe shi da ikon trisants mai iya ba da izinin ba da izinin wutan da za a juya. Ana nutsar da samfuran canja wuri a matsakaici canja wurin zafin da ke ƙasa na al'ada, a lokacin da harafin kai ya juya da kashi 180 °) wanda ya dogara da girman samfuran samfuri da tauri. Sannan yi amfani da adadin goniyer don sanin adadin ƙimar ƙira, kusurwar murguda hankali da kuma taurin kayan roba. A hankali zazzabi a hankali ya karu a wannan lokacin, kuma wani makirci na kusurwar murdiya a kan zazzabi an samu. Yanayin yanayin zafi wanda modulus ya kai T2, T10, da T100 yawanci ana yin rikodin daidai da darajar modulus a zazzabi a ɗakin.
5. Low zazzabi maimaitawa (try gwajin)
Ana amfani da gwajin TR don kimanta ikon ƙirar da aka tsara a cikin jihar har abada da dawwama na har abada wanda aka ƙayyade don tantance ƙarancin zafin jiki. Kamar yadda aka rufe a baya, polymers da yawa kamar NR da PVC za su yi kuka a ƙarancin yanayin zafi, amma shimfiɗa ma zata iya yin kuka, jagoranta zuwa ƙarin dalilai yayin kallon ƙananan kayan tsire-tsire. Don aikace-aikace na kimantawa kamar yadda aka dakatar, Trashin da ke cikin tashin hankali ya dace sosai kuma ana amfani da shi akai-akai. A cikin wannan gwajin, samfurin yana da elongated (sau da yawa ta 50% ko 100% ko 100%) da daskarewa a cikin jihar elongated. An sake tantance samfuran, a lokacin da ake fitar da zafin jiki a wani ƙimar ƙayyadaddun don auna dawo da ƙira, tsawon shrinkage ana yin rikodin kuma elongation an yi rikodin shi kuma ana yin rikodin tsawan. Yanayin yanayin zafi wanda aka lalata samfurin da 10%, 30%, da kashi 70, da kuma 70% ana lura dasu azaman Tr50, tr30, tr50, da tr70. Tr10 ya danganta ga zafin jiki; Tr70 ya danganta ga lalata na dindindin a cikin matsakaicin matsakaiciyar-zazzabi; Kuma bambanci tsakanin Tr10 da Tr70 ana amfani da su don auna luximin da ƙirar (mafi tsananin bambanci, mafi girma da kuka ɗauka).
6. Lowerancin zafin jiki na damuwa na damuwa (CSR)
Za'a iya amfani da gwajin CSR don yin annabta game da aikin da rayuwar suttukan kayan. A lokacin da aka ba da wani fili mai kyau, wanda aka kirkira wani karfi, da kuma ikon kayan don kiyaye wannan karfin muhalli yana auna da safa. Duk hanyoyin da suka shafi jiki da sunadarai suna ba da gudummawa ga annashuwa na jiki, bisa kan lokaci, gwargwadon abin kwanciyar hankali, wanda ke haifar da tsarin cirewar jiki, da kuma faruwar tsarin cire danniya, da kuma faruwar tsarin cire danniya, da kuma annashuwa tsarin cire danniya, da kuma annashuwa tsarin cire danniya, da kuma faruwar tsarin cire danniya. A mafi girma yanayin zafi, da tsarin sunadarai yana tantance adadin annashuwa, lokacin da matakai na zahiri sun riga sunadarai, suna haifar da rashin daidaituwa na sarkar. Hawan zazzabi ko kwatsam yana ƙaruwa da yawan zafin jiki na iya samun tasiri akan annashuwa na damuwa a cikin elastomers. A lokacin gwajin CSR, an sanya samfurin gwaji
A lokacin gwajin CSR, ana ƙaruwa da kwanciyar hankali lokacin da samfurin gwajin ya yiwa yanayin yanayin zafi. Idan danniya hutu yana faruwa da wuri a cikin gwaji, yawan ƙarin farfadowa yana ƙaruwa da farko kuma yana da matsakaicin darajar yayin sake zagayowar farko. A cikin manyan kayayyaki na gwaji don samar da samfurori (19mm na waje diamita, da diamita na ciki, sannan kuma a ci gaba da gyara zuwa 4mm, da ƙasa zuwa zazzabi na gaba ɗaya 20, kuma a gaba zuwa lokacin zazzabi a tsakanin -20 ℃ A cikin 24h, duk lokacin jarabawar a gwajin zazzabi, zazzabi gwajin, ci gaba da yanke hukunci. Ana yin ma'aunin ƙarfi ci gaba a duk lokacin gwaji a zazzabi gwajin.
7. Tasirin abun ciki na Ethylene
Abun da ke cikin Ethylene yana da babban tasiri a kan ƙarancin zafin jiki na poldm polymers. Polymers tare da ethylene abun ciki jere daga 48% zuwa 72% aka kimanta karkashin manyan hanyoyin gado. Dukkanin manufar rage bambancin a cikin dankalin Mooney ta gabatar da enb a cikin wadannan polymers daban-daban.
Epdm roba yana amorphous idan da ethylene daidai yake da kuma rarraba abubuwan biyu a cikin sarkar polymer. EPDM tare da 48% da 54% abun ciki na ethylene baya kuka a ko sama da dakin da zazzabi. Lokacin da abun ciki na Ethylene ya kai kashi 65%, jerin na Ethylene sun fara karuwa cikin lamba da tsayi kuma na iya samar da lu'ulu'u, waɗanda aka lura da su a cikin korar kerestall a cikin 40 ° C. Mafi girma the DSC kololuka, mafi girma lu'ulu'u wancan form.
7.2 Baya ga sakamakon abun ciki na Ethylene a kan ƙananan yawan zafin jiki da aka tattauna daga baya, girman crystallite yana shafar sauƙin haɗuwa da sarrafa maharan da ke ɗauke da lu'ulu'u. Mafi girman girman cystallite, ana buƙatar ƙarin zafi a aikin ƙarfin aiki a matakin haɗuwa don cakuda polymer tare da sauran abubuwan polymer tare da sauran kayan aikin. Thean roba karfin roba na EPDM mahaɗan yana ƙaruwa tare da kara yawan abun cikin Ethynene. A cikin tsarin rufewa inda aka auna sakamakon abun ciki na abun ciki, karuwa a cikin abun ciki na Ethylene daga kashi 50% zuwa 68% ya haifar da ƙarancin ninka na roba. Harshen zazzabi yana ƙaruwa tare da ƙara yawan abun cikin Ethynene. A bakin gefen wuya na amorphous polymer polymer shine 63 °, yayin da gefen gefen wuya na polymer tare da mafi girman abun ciki shine 79 °. Wannan ya faru ne saboda karuwa cikin jerin Elthylene, karuwa a cikin lu'ulu'u a cikin m a m, da karuwa da dacewa a cikin polymers thermoplast.
7.3 Lokacin da aka auna taurin kai a yanayin zafi mai rauni, sabanin abubuwan polymer da ke ɗauke da canji mafi girma ethylene baya nuna mafi girman yanayin a yanayin zafi.
Saitin matsawa ta 7.4 ya dogara da yawan zafin jiki. Idan an gwada shi a 175 ° C, babu wani banbanci a cikin tsayarwar matsakaiciyar tsakanin kowane ɗayan polymers (saiti yana tasiri da ƙirar tsarin kuma zaɓi na tsarin rashin daidaituwa). Bayan narkar da lu'ulu'u na Ethylene, polymer ɗin ya nuna wani nau'in amorphous, kuma don bincika tasirin abun cikin Ethylene, an yi shi ne a 23 ° C. Polymers tare da mafi girman abun ciki na bayyane suna da nakasassu na dindindin (fiye da sau biyu), da tasirin abun cikin Ethylene ya fi girma idan -20 ° C. Polymers tare da fiye da 60% na ethylene abun ciki suna da nakasassu na dindindin (> 80%); A -40 ° C, kawai polfors cikakken amorphous suna da ƙarancin nakasa na dindindin (17%).
7.5 Sakamakon abun ciki na Ethylene akan ƙarancin zafin jiki na Hardening daga Gwajin Gehman Gehman. Bayar da zazzabi, mafi girma kusurwa, ƙananan karuwa cikin tauri (ko karuwa a cikin modulus). A low yanayin zafi, moduless modulus yana ƙaruwa sosai tare da haɓaka abun ciki na Ethylene. Don poluffius polymers, T2 shine -47 ° C, yayin da mafi girman yanayin polymer na ciki yana da T2 na kawai -16 ° C.
7.6Tr auna Shrinkage dawo da samfur bayan tsawan abubuwan daskarewa, abun ciki na Ethylene yana da tasiri sosai akan hanyar gwajin, wanda ya sake yi da gwajin Gehman.
Wannan yayi kama da gwajin Gehman. Shrinkage (%) na polymers daban-daban sun bambanta a matsayin aikin zazzabi, tare da poluphous polymers da da da da da da da da ke da maimaitawa a yanayin zafi; Koyaya, kamar yadda annabta, dawo da abin da ya lalace yayin da abun ciki na Ethylene yana ƙaruwa da zazzabi da aka bayar.
farfadowa da lalacewar. Darajar Tr10 ta bambanta da -53 ° C don poluffus polymers zuwa -28 ° C don polymers tare da babban abun ciki.
7.7 danniya damuwar damuwa (CSR) maimaitawa
Sake zagayowar. Click da mahadi, ba su damar shakata da 25 ° C na 24 h, sannan sanya su cikin yanayin yanayin zafi da ke faruwa a 240 h. Lokacin da aka matsa a karo na farko, bayan lokacin daidaitawa, polystalline polymer e yana da rashi mai ban sha'awa fiye da nazara polymer (mafi girman polymer karfi na damuwa (mafi girma F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / F / FT). Haji da mahaɗan zuwa 110 ° C ya dawo da karfinta na hatimi, kuma lokacin da aka dawo da karfin polyster, da kuma polymer karuwa da mafi girma daga polymer na polyalline. Matsakaici na gaba yana ba da irin wannan ƙarshe. A bayyane yake cewa kayan kwalliyar kwalliya suna da fifikon aikace-aikacen da aka ɗora inda ake buƙata masu girma da ƙarancin zafin jiki.
8. Tasiri da abun ciki diolefin
Don samar da ma'anar da ba a buƙata don m, diofug mai yawa kamar enb, an ƙara HX da DCPD zuwa Uthylene propylene polylene. Umarni biyu yana aiki a cikin matrix na polymer, yayin da na biyu abubuwa a matsayin biyan kuɗi zuwa sarkar kwayoyin cutar kuma tana samar da ma'anar rashin daidaituwa don ɓarna ta sulfur. Tasirin Enb an kimanta shi a cikin iska mai iska (ruwan sama). Polymers dauke da 2%, 6% kuma 8% enb an kwatanta.The Modulus ya karu yayin da elongation ya ragu sosai. Tauyin ya karu kuma matsawa yana da haɓaka a lokacin tashi zuwa zazzabi. Kamar yadda Enb abun ciki ya karu, lokacin mai biyan bashi ya ga gajarta.
Enb shine kayan amorphous, kuma idan aka ƙara wa polymer baya, sai ya rushe abun ciki na polymer, don haka polymers da za'a iya samu iri ɗaya, kuma mafi girman abun ciki na entb yana inganta ƙananan ƙananan tsire-tsire. A zazzabi dakin da, mafi girma enb abun ciki dan kadan yana inganta matsawa da aka saita saboda ingantattun yawa. Koyaya, a ƙarancin yanayin zafi, saitin da aka saita na polymers tare da mafi girma enb ya zama mafi kyau fiye da na polymers tare da abun ciki 2% enb abun ciki. Tasirin abun ciki na Enb akan zazzabi, maimaitawa, da gwajin Gehman, kowane polymer ya nuna cigaba a cikin kayan masarufi tare da kara abubuwan da ake ciki.
9. Tasirin gyaran Mooney akan kayan ƙananan zazzabi
Sanannen abu ne cewa ƙwayar Mooney) tana da tasiri mai mahimmanci akan aikin sarrafa elastomers. A cikin cirewa da aikace-aikacen da aka gyara a cikin cirewa da aikace-aikace masu gyara, yana da mahimmanci don zaɓar fili tare da darajar danko na Mooney. Ta amfani da irin tsari iri ɗaya da aka yi amfani da shi don bincika sakamakon na uku mononey, enb, da kuma danko na Mooney. Tenarfin tenarshe, modulus, da kuma roba karogomar ya karu da kara danko na Mooney. Tasirin gyaran Mooney akan ƙananan yawan zafin jiki na EPDM bai da muhimmanci. Koyaya, rashin matsari na dindindin a zazzabi a ɗakin, -20 ° C da -40 ° C ya ƙaru tare da ƙara yawan ƙwayar ƙwayar ƙwayar ƙwayar ƙwayoyin cuta. Koyaya, matsawa ya faɗi a zazzabi a ɗakin, -20 ° C) ba su canza wasu canje-canje na molarfin growy na VIMDM adeciities.
10. Kammalawa
Abun cikin mahaifa da diolefin abun ciki yana da tasiri sosai a kan aikin epdm elastomers a cikin ƙananan abubuwan da ke cikin ƙasa mai ƙarfi, tare da ƙarancin ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar cuta na phaterene na polymer. Yakamata a yi amfani da petmers mara amfani a lokacin da ƙarancin yawan zafin jiki shine iyakancewa.
