Loko a PTFE high-temperature adhesive tape yitirhisiwa eka ndzhawu yo hisa – hiku vula, 200°C kuringana mavhiki kumbe tinhweti – silicone pressure-sensitive adhesive (PSA) yinga cinca. Matimba ya peel yanga tlakuka, ya wa, kumbe ku hundzisela masalela. Ku hlangana ku nga ha engeteleka (ku brittleness) kumbe ku hunguteka (ku tsandzeka ka ku hlangana).
A hi ti-PSA hinkwato ta silicone leti tikhomaka hi ndlela leyi fanaka. Kuhambana ku fika ehansi eka xivumbeko xa polymer (methyl vs. methylphenyl), crosslinking mechanism (peroxide vs. addition cure), na ratio ya MQ resin kuya eka rhaba.
Aokai PTFE yi tirhisa tigiredi to tala ta silicone PSA eka tithepi ta hina. Nkongomiso lowu wu hlamusela leswi humelelaka eka matimba ya peel xikan’we naku hlangana endzhaku ka ku dyuhala ka mahiselo yale henhla eka giredi yin’wana na yin’wana, na ndlela yo hlawula leyi faneleke eka xitirhisiwa xa wena.
Leswi Humelelaka Hi Silicone PSA Ehansi Ka Ku Hisa – Tindlela Timbirhi To Hluleka
Loko ti dyuharile eka mahiselo yale henhla (200-250°C), ti silicone PSAs tinga endla ku cinca kambirhi loku kanetanaka:
1. Post-crosslinking (swi yisa eka ku brittleness) .
Mintlawa ya ntirho leyi nga angulangiki yi ya emahlweni yi angula, yi engetela crosslink density. Matimba yosungula ya peel yanga tlakuka swa xinkarhana, kutani ya wa swinene loko xinamarheti xiva xi tiya swinene. Matimba ya static shear ya vonaka ya tlakuka, kambe matimba yo khoma na ku lwisana na ku khumbeka swa onhaka. Filimi leyi namarhelaka yi tiya naswona ya pandzeka.
2. Ku onhaka ka marhambu ya nkolo (swi yisa eka ku lahlekeriwa hi madzovo na masalela) .
Nkolo wa polydimethylsiloxane wu endla cyclization na chain scission. Matimba ya peel ya hunguteka hiku ya emahlweni. Xinamarheti xinga hundzisela eka substrate (masalela) kutani xi tsandzeka hiku hlangana. Leswi switala kuva eka ti methyl silicone PSAs ta xiyimo xale hansi.
Tipharamitha ta nkoka ta ku cinca-cinca:
Nhlayo ya phenyl (ya le henhla = ku tiya ka ku hisa ku antswa) .
Crosslink density na muxaka wa ku horisa (ku horisa ka ku engeteriwa vs. ku horisa ka peroxide) .
Ratio ya MQ resin kuya eka rhaba ya silicone
Ku Hlawuriwa ka Giredi hi Xivumbeko xa Tikhemikhali
1. Polydimethylsiloxane leyi tolovelekeke (silicone ya muxaka wa methyl PSA) .
Ku khomiwa ka madzovo endzhaku ka ku dyuhala (200-250°C): Matimba ya madzovo ya tlakuka nyana ekusunguleni, kutani ya hunguteka. Endzhaku ka masiku ya 7 eka 250°C, ku khomiwa ka madzovo i 50-70% ntsena . Matirhelo ya hunguteka hiku hatlisa eka mahiselo yale henhla. Ku onhaka swi huma eka cyclization ya dimethyl siloxane backbone.
Ku tshamiseka ka cohesion: Ti version leti horisiweke hi peroxide (xikombiso, KR-101) tina ti residual initiators leti vangaka ku nga lawuriwi endzhaku ka ku horisiwa – adhesive hardens and embrittles. Matimba yosungula ya shear ya antswisiwa, kambe matimba yo khoma ya hunguteka, naswona ku tsandzeka ka cohesive swihumelela ehansi ka kuhisa. Ti versions leti horisiweke hi addition ti antswa nyana kambe tahari na swipimelo hiku tiya ka inherent heat resistance ya dimethyl backbone.
2. Methylphenyl polysiloxane (giredi leyi nga ni mahiselo ya le henhla) .
Ku khomiwa ka peel endzhaku ka ku dyuhala: Phenyl side chains yi kavanyeta ku pakiwa ka nkarhi na nkarhi ka swiphemu swa dimethyl naswona yi tshikelela ku onhaka ka cyclization. Endzhaku ka masiku ya 7 eka 250°C, ku khomiwa ka matimba ya peel swi tlula 85% . Ti formulations ta high-phenyl ti hlayisa swivumbeko swa peel leswi tiyeke hambi kuri eka 260-288°C.
Ku tshamiseka ka ku hlangana: Swi kahle swinene. Matimba ya shear ya cinca nyana; ku khomiwa ka matimba ku tlula 80%. Leyara ya adhesive yitshama yirikarhi yi olova kuringana nkarhi woleha handle ka embrittlement kumbe masalela. Ti grades ta high-phenyl leti horisiweke hiku engeteriwa i premium thermally stable silicone PSA.
3. Tigredi to hlawuleka ta ntolovelo ta high-peel na low-peel
Ti grade tale henhla ta peel (xikombiso, Dow 7385, typical peel >10N/25mm): Ku layicha ka resin ya MQ yale henhla swinyika tack yosungula ya kahle swinene xikan’we na matimba ya peel, kambe hi ntsengo wa ku tiya ka kuhisa xikan’we naku tshamiseka ka cohesion. Tikombisa ku hunguteka lokukulu ka peel endzhaku ka ku dyuhala naswona titala kuva na masalela hikokwalaho ka resin thermal decomposition. Tirhisa ntsena eka switirhisiwa swa mahiselo yale hansi leswinga tshamisekangiki.
Ti grade ta filimi yo sirhelela ya peel yale hansi, ya cohesion yale henhla: Crosslink density yale henhla yinyika matirhelo ya peel lawa ya tiyeke xikan’we naku tiya ka kahle swinene ka ku dyuhala, kambe tack yosungula yale hansi. Endzhaku ka ku dyuhala, ti tshama ti ri leti hlanganeke kambe ti nonoka, leswi hungutaka ku fambisana ni swilo leswi nga ni swiganga.
Ndlela yo hlanganisa – Peroxide vs. Ku tshungula ku engetela (Same Methyl Base) .
Hambi ku ri hi methyl polymer leyi fanaka, ndlela yo horisa yi cinca swinene mahanyelo ya ku dyuhala.
1. Peroxide-cured (xitukulwana xo sungula lexi tolovelekeke) .
Peroxide leyi saleke yi hlohletela post-crosslinking leyinga lawuriwiki hinkarhi wa ku dyuhala ka mahiselo yale henhla.
Matimba ya peel ya spike ekusunguleni, kutani ya wa swinene.
Ku hlangana ku tlakuka swa xinkarhana, ku landzela ku tshoveka na ku tsandzeka ka gezi ro khoma.
Ku tshamiseka ka ku dyuhala ka ntlawa kuya eka ntlawa aswi kahle.
2. Ku horisiwa hi ku engeteriwa (ku horisiwa hi hydrosilylation) .
Cure a yi humesi swilo leswi nga riki swa nkoka; crosslink network yi lawuriwa kahle.
Ku cinca ka nhundzu endzhaku ka ku dyuhala ku landzela ntshamiseko wa linear lowu nga languteriwaka.
Ku khomiwa ka madzovo yale henhla swinene xikan’we naku tshamiseka ka cohesion loko ku pimanyisiwa na swivumbeko swa peroxide.
Nkongomiso wa ku Hlawula Giredi
Xiyimo xa Vutirheli
Giredi leyi Hlamuseriweke
Hikokwalaho ka yini
Kuya emahlweni ka mahiselo yale henhla (>200°C), peel leyi tiyeke, zero residue
Ku horisiwa hi ku engeteriwa, loku nga na phenyl ya le henhla (xikombiso, Dow 7388, Q2-7406) .
>85% ku khomiwa ka peel, kungari na embrittlement, >80% ku khoma matimba yo khoma
Ku hisa lokukulu ka nkarhi wo koma loku nga tshamisekangiki, loku nga durhiki
Standard methyl-type, leyi horisiweke hi ku engeteriwa, leyi horisiweke endzhaku ka ku baka (xikombiso, 7657) .
Swi amukeleka kambe langutela ku onhaka kun’wana ka peel xikan’we na embrittlement leyinga endlekaka eka swirhendzevutani swo leha
A hi ku hisa lokukulu loku yaka emahlweni; langutela masalela endzhaku ka ku dyuhala
Filimi yo sirhelela, ku hlangana ka le henhla, tack ya le hansi
High-crosslink ya xiyimo xale hansi xa peel
Ku tshamiseka lokunene ka ku dyuhala kambe ku nonoka naswona ku nga fambisani ngopfu
Xitsundzuxo xa Aokai PTFE : Eka thepi yin’wana na yin’wana ya PTFE leyi nga ta vona mahiselo lama nga heriki yale henhla ka 200°C, boxa addition-cured methylphenyl silicone PSA. Ntsengo wa upfront wule henhla, kambe wu sivela ku tsandzeka ka nsimu leswi vangiwaka hi masalela ya adhesive kumbe ku lahlekeriwa hi bond.
Nkatsakanyo – Ku fambelanisa Giredi ya Silicone PSA na Xilaveko xa ku Hisisa
Methyl-type silicone PSA (ngopfu ngopfu peroxide-cured) yi lulamerile ntsena eka ku tirhisiwa ka nkarhi na nkarhi kumbe eka mahiselo yale hansi. Endzhaku ka masiku ya 7 eka 250°C, langutela 30-50% wa ku lahlekeriwa hi peel xikan’we na embrittlement leyinga endlekaka.
Methylphenyl (high-phenyl) silicone PSA yi hlayisa >85% wa matimba ya peel xikan’we naku hlangana loku olovaka endzhaku ka ku dyuhala loku fanaka. I nhlawulo wa vukorhokeri lebyi yaka emahlweni bya 200-250°C.
Ti grade ta high-peel ti cincana ku tiya ka ku dyuhala eka tack yosungula – papalata eka switirhisiwa swo hisa.
Eka ku lava ku hlanganisiwa ka mahiselo yale henhla, Aokai PTFE yi tirhisa ti addition-cured methylphenyl silicone PSAs. Hinga nyika data ya peel retention endzhaku ka 1000h eka 250°C loko ku komberiwa.
Ku kuma vuxokoxoko bya ti-datasheet ta xithekiniki na swintshuxo swa ntolovelo swa malapi ya mahiselo ya le henhla ya PTFE, tithepi, mabandhi ya mesh, na swin’wana:
Hi ku namarhela vutshila na vutshembeki, hi nyika swintshuxo leswi endleriweke ku yima kan’we na vukorhokeri bya le ndzhaku ka ku xavisiwa lebyi anakanyisisiweke.
