NBR kumfa (kumfa roba nitrile) da silicone kumfa (silicone rubber foam), a matsayin roba biyu da aka yi amfani da shi sosai{0}kayan kumfa, suna nuna ainihin ka'idodin kumfa na asali daban-daban da kaddarorin kayan aiki saboda bambancin tsarin kwayoyin halittarsu da hanyoyin halayen sinadaran. Waɗannan bambance-bambance kai tsaye suna ƙayyade ma'aunin zaɓi na kowane abu a cikin aikace-aikacen masana'antu.
Daga hangen ainihin tsarin kumfa, NBR kumfa yana dogara ne akan aikin haɗin gwiwa na babban -zazzabi na lalata kumfa da sulfur vulcanization giciye - haɗi. Kashin bayan kwayoyin halitta na NBR ya ƙunshi carbon-carbon bond (C–C), tare da ƙungiyoyin gefe masu ɗauke da acrylonitrile ({4}}CN) da butadiene double bonds (C=C). Tsarinsa na kumfa yana faɗuwa ƙarƙashin nau'in nau'in kumburin kumburin ƙwayar cuta iri-iri. A cikin samar da masana'antu, azodicarbonamide (AC), sodium bicarbonate, ko N, N'-dinitrosopyramidetetramine (DPT) yawanci ana amfani da su azaman abubuwan busawa. Lokacin da zafin jiki ya tashi zuwa digiri 150-180, waɗannan nau'ikan busawa suna jurewa bazuwar thermal, suna sakin iskar gas kamar N₂, CO₂, da NH₃. Waɗannan iskar gas suna faɗaɗa a cikin NBR narke don samar da pores. A lokaci guda, halayen sulfur vulcanization suna faruwa a lokaci guda, wanda ke haifar da ƙetare - haɗin haɗin gwiwar butadiene biyu da samuwar tsarin cibiyar sadarwa na C-C da C-S-C, a ƙarshe yana daidaita yanayin halittar jiki. Mahimmancin wannan gicciye- cibiyar sadarwar da aka haɗa ta ta'allaka ne a cikin haɗakar hulɗar carbon{17}}haɗin carbon ta gadoji na sulfur, tare da giciye - haɗin haɗin gwiwa galibi ya ƙunshi C-S-C da guda/biyu sulfur bonds. Saboda ƙarancin ƙarfin haɗin gwiwa, waɗannan cibiyoyin sadarwa suna nuna ƙayyadaddun kwanciyar hankali.
Sabanin haka, tsarin kumfa na silicone ya haɗa da amsawar platinum -catalyzed giciye{1}} haɗawa da juyin halittar hydrogen a wurin kumfa, wanda ya ƙunshi tsarin kumfa mai kama da juna. Matrix na kumfa silicone shine polydimethylsiloxane (PDMS), tare da kashin bayan kwayoyin halitta wanda ya ƙunshi silicon - oxygen bond (Si-O-Si) da ƙungiyoyin gefen methyl (-CH₃). Ana samun kumfa da warkewa galibi ta hanyar amfani da tsari guda biyu-: Bangaren A ya ƙunshi man siliki na vinyl mai ɗauke da Si–CH=CH₂, yayin da Bangaren B ya ƙunshi hydrogen{8}mai ɗauke da man silicone tare da haɗin Si-H da ma'adinin platinum. Yayin da ake amsawa, matakai guda biyu masu mahimmanci suna faruwa a lokaci guda: na farko, platinum{10}}catalyzed giciye -haɗin kai inda Si-CH=CH₂ bond tare da Si-H don samar da Si-C bonds, kunna colloid curing; na biyu, yanayin kumfa na juyin halitta na hydrogen inda Si-H ke amsawa da Si-OH don samar da haɗin Si-O-Si kuma ya saki H₂. hydrogen yana ƙullawa kuma yana faɗaɗa cikin matrix polymer, a ƙarshe yana samar da tsarin rufaffiyar tantanin halitta ko buɗe{15}}. Giciye- cibiyar sadarwar da aka haɗe ta kewaye da manyan sarƙoƙi na Si-O-Si da Si–C{18} hanyoyin haɗin gwiwa, tare da Si-O bonds suna nuna kuzarin har zuwa 452 kJ/mol{20}} fiye da 347 kJ/mol na C–C bond a cikin NBR{{22} (PMC, 2025; MDPI, 2024).
Dangane da kaddarorin kayan, bambance-bambancen da ke tsakanin kayan biyu suna nunawa da farko a cikin mahimman alamomi kamar juriya na zafin jiki, juriya na sinadarai, kayan injin, da kwanciyar hankali na muhalli. Daga ainihin hangen nesa na zahiri, NBR kumfa yana da yawa na 0.3–0.8 g/cm³, a Shore A taurin digiri 20–70, galibi rufaffiyar tsarin -tsarin tantanin halitta tare da girman pore daga 50-300 μm da porosity na 40-70%. Sabanin haka, silicone mai kumfa yana nuna ƙananan ƙarancin (0.2-1.1 g / cm³), taurin mai laushi (Share A 1-50 digiri), ƙarin nau'in pore masu girma (20-100 μm), kuma mafi girma porosity (50-80%). Bayanan gwaji sun nuna cewa daidaiton girman pore ɗin sa ya fi 40% sama da na kumfa NBR (MDPI, 2024; PMC, 2025).
Juriya na thermal shine ɗayan mafi mahimmancin bambance-bambance tsakanin kayan biyu. NBR kumfa yana da tsayin tsayin sabis na zazzabi na -30 digiri zuwa digiri +120 , tare da asarar zafi na 5% yana faruwa a kusan digiri 280 . Bayan tsufa a digiri 150 na tsawon sa'o'i 72, yana nuna hardening, raguwa na 10-15%, da asarar elasticity fiye da 50%. Sabanin haka, kumfa silicone na iya jure yanayin zafi mai tsawo daga -60 digiri zuwa digiri +230 da kuma jure wa ɗan gajeren lokaci - bayyanarwa zuwa digiri 280, tare da asarar nauyi na 5% yana faruwa a kusan digiri 480 . Ko da bayan tsufa a digiri 200 na sa'o'i 72, nakasar matsi ta dindindin ta kasance ƙasa da ko daidai da 30%, kuma riƙewar sa na roba ya wuce 70% (bayanai daga Fasahar Rocket Rocket, 2019). Babban dalilin wannan bambance-bambance ya ta'allaka ne a cikin rarrabuwar kawuna a cikin ƙarfin haɗin sinadarai: babban kwanciyar hankali na Si-O bond yana ba da damar silicone don tsayayya da lalacewa ƙarƙashin yanayi mafi girma{27}}.
Dangane da juriyar yanayin zafi, wani kamfani na kasar Sin ya ƙera wani kumfa na silicone wanda zai iya jure yanayin zafi na digiri 315 na ɗan gajeren lokaci.
Dangane da juriya na sinadarai, kumfa NBR yana nuna juriya mai ban mamaki, yayin da silicone mai kumfa yana nuna kyakkyawan aiki akan acid, alkalis, ozone, da radiation ultraviolet. Bayanan gwaji daga Wiley (2019) sun nuna cewa bayan nutsewa a cikin man injin # 3 a digiri 100 na sa'o'i 72, canjin ƙarar kumfa na NBR ya kasance kawai 2.1%, yana nuna kyakkyawan haƙuri ga mai ma'adinai, man injin, da man dizal, da kuma juriya mai kyau ga aromatics da esters; duk da haka, aikin sa akan acid, alkalis, da ruwa matsakaita ne. Sabanin haka, silicone mai kumfa ya nuna adadin haɓaka girma har zuwa 42.7% a ƙarƙashin yanayi iri ɗaya, yana nuna ƙarancin juriyar mai amma na musamman haƙuri ga acid, alkalis, ruwa, ozone, da UV radiation, tare da rayuwar sabis na waje na shekaru 20-30 ba tare da tsufa ba. Idan aka kwatanta, NBR kumfa yana da tsawon rayuwar waje na shekaru 3-5 kawai kuma yana tasowa bayan tsufa na ozone (50 ppm, 40 digiri, 72 h), yayin da UV tsufa na tsawon sa'o'i 300 yana haifar da hardening, brittleness, da powdering surface (bayanin da aka ambata daga Journal of Wuhan University, 2022).
Dangane da kaddarorin injiniyoyi, kumfa NBR yana nuna ƙarfin ƙarfi mai ƙarfi (0.8-2.5 MPa), nakasar matsawa ta dindindin (25%,72 h, 70 digiri) Kasa da ko daidai da 25%, da matsakaicin juriya (50-60%). Silicone foamed yana nuna ƙananan ƙarancin ƙarfi (0.5-0.8 MPa) amma mafi girman tsayin daka a lokacin hutu (Fiye da ko daidai da 300%) da ƙarfin juriya (70-85%), tare da ingantaccen kwanciyar hankali na inji a ƙarƙashin yanayin yanayin zafi{15}sa nakasar na dindindin ta zama ƙasa da 30% a Jami'ar Wuhan 2002. Game da jinkirin harshen wuta da aminci, NBR kumfa yana buƙatar masu kare harshen wuta don cimma juriyar harshen wuta da kai - yana kashe kadarori bayan cirewa daga harshen wuta; yana fitar da hayaki mai yawa yayin konewa kuma yana fitar da iskar gas mai guba kamar CN⁻ da SO₂. Sabanin haka, silicone mai kumfa yana da jinkirin harshen wuta, saduwa da UL94 V -0 ƙa'idodi, ba{25}}mai ƙonewa ba, hayaki{26}} kyauta, kuma mara{27}mai guba/ƙamshi, yana biyan buƙatun abinci (FDA 21 CFR 177.2600).
A taƙaice, bambance-bambancen da ke tsakanin kumfa na NBR da silicone mai kumfa ya samo asali ne daga tsarinsu na asali daban-daban na kwayoyin halitta da tsarin kumfa/giciye - hanyoyin haɗin kai: NBR kumfa yana da sarkar carbon{1}, yana samun siffarsa ta hanyar sulfur vulcanization da thermal bazuwar, yana ba da ƙarfin juriya na mai da ƙananan farashi, amma tare da iyakancewar yanayin zafi da juriya da yanayin zafi. Silicone mai kumfa yana dogara ne akan siliki{2}}kashin bayan iskar oxygen, inda giciye{3}haɗin da platinum ke haɗawa yana faruwa lokaci guda tare da juyin halittar hydrogen yayin kumfa, yana nuna juriya na musamman na zafin jiki, juriyar tsufa, da aminci, kodayake yana da ƙarancin juriyar mai da tsada. Waɗannan bambance-bambancen halayen suna ba da ƙayyadaddun yanayin aikace-aikacen kowane abu kuma suna ba da ingantaccen tushe don zaɓin masana'antu.
Idan ba ku da tabbacin yanayi kuna amfani da kumfa NBR da kumfa na silicone, zaku iya kwangilar mu don samun takaddun bayanai da Sabbin Ci gaban Ci gaban takardar soso na silicone.