Lapho a Itheyiphu yokunamathela ye-PTFE ephezulu yokushisa isetshenziswa endaweni eshisayo - yithi, 200°C amaviki noma izinyanga - i-adhesive ye-silicone ezwela ukucindezela (PSA) ingashintsha. Amandla e-peel angase akhuphuke, awe, noma adlulise izinsalela. Ukubumbana kungase kukhule (ukuqina) noma kunciphe (ukwehluleka ukuhlangana).
Akuwona wonke ama-PSA we-silicone aziphatha ngendlela efanayo. Umehluko wehlela ekubunjweni kwe-polymer (i-methyl vs. methylphenyl), indlela yokuxhumanisa (i-peroxide vs. ukwelapha okungeziwe), kanye nesilinganiso se-MQ resin nerabha.
I-Aokai PTFE isebenzisa amamaki amaningi e-silicone e-PSA kumateyipu ethu. Lo mhlahlandlela uchaza ukuthi kwenzekani ekuxebuleni amandla nokubumbana ngemva kokuguga okuphezulu kwezinga lokushisa kwebanga ngalinye, nokuthi ungakhetha kanjani elifanele lohlelo lwakho lokusebenza.
Kwenzekani ku-Silicone PSA Ngaphansi Kokushisa - Izindlela Ezimbili Zokuhluleka
Uma isikhulile ekushiseni okuphezulu (200-250°C), ama-PSA e-silicone angabhekana nezinguquko ezimbili eziphikisanayo:
1. Ngemuva kokuxhumanisa (kuholela ekubeni brittleness)
Amaqembu asebenzayo angaphenduliwe ayaqhubeka nokusabela, andisa ukuminyana kwe-crosslink. Amandla ekhasi lokuqala angakhuphuka okwesikhashana, bese ewa kakhulu njengoba okunamathelayo kuba lukhuni kakhulu. Amandla okugunda okumile abonakala enyuka, kodwa ukubamba amandla kanye nokumelana nomthelela kuyawohloka. Ifilimu yokunamathisela iba nzima futhi iyaqhekeka.
2. Ukuwohloka komgogodla (kuholela ekulahlekeni nezinsalela)
I-polydimethylsiloxane backbone idlula i-cyclization kanye ne-chain scission. Amandla e-peel ehla ngokuqhubekayo. I-adhesive ingase idlulisele ku-substrate (insalela) noma ihluleke ngokuhlangene. Lokhu kuvamile kuma-PSA e-methyl silicone aphansi.
Amapharamitha wokumodela angukhiye:
Okuqukethwe kwe-Phenyl (okuphezulu = ukumelana nokushisa okungcono)
Ukuminyana kwe-Crosslink kanye nohlobo lokwelapha (ukwelapha okungeziwe ngokumelene nokwelashwa kwe-peroxide)
Isilinganiso se-MQ resin kuya kurabha ye-silicone
Izigaba Zebanga Ngesakhiwo Sekhemikhali
1. I-polydimethylsiloxane ejwayelekile (i-methyl-type silicone PSA)
Ukugcinwa kwesikhumba ngemva kokuguga (200-250°C): Amandla e-peel akhuphuka kancane ekuqaleni, bese ehla. Ngemuva kwezinsuku eziyi-7 ku-250 ° C, ukugcinwa kwamakhasi kungu- 50-70% kuphela . Ukusebenza kwehla ngokushesha emazingeni okushisa aphezulu. Ukuwohloka kuvela ekujikelezweni komgogodla we-dimethyl siloxane.
Ukuzinza kokubumbana: Izinguqulo ezilashwe nge-Peroxide (isb, i-KR-101) zineziqalisi eziyinsalela ezibangela ukuphulukiswa okungalawuleki - okunamathelayo kuyaqina futhi kufake i-embrittles. Amandla okuqala okugunda ayathuthuka, kodwa ukubamba amandla kuyehla, futhi ukwehluleka okuhlangene kwenzeka ngaphansi kokushisa. Izinguqulo ezelashiwe zingcono kancane kodwa zisanqunyelwe ukumelana nokushisa okungekuhle komgogodla we-dimethyl.
2. I-Methylphenyl polysiloxane (ibanga elimelana nezinga lokushisa eliphezulu)
Ukugcinwa kwesikhumba ngemva kokuguga: Amaketanga aseceleni e-Phenyl aphazamisa ukupakishwa okujwayelekile kwezingxenye ze-dimethyl futhi acindezele ukuwohloka kwe-cyclization. Ngemva kwezinsuku ezingu-7 ku-250°C, ukugcinwa kwamandla e-peel kudlula ama-85% . Ukwakhiwa kwe-phenyl ephezulu kugcina izici ezinzile zekhasi ngisho naku-260-288°C.
Ukuzinza kokubumbana: Kuhle kakhulu. Amandla e-shear ashintsha kancane; ukubamba ukugcinwa kwamandla kudlula u-80%. Isendlalelo se-adhesive sihlala siguquguquka isikhathi eside ngaphandle kwe-embrittlement noma izinsalela. Amamaki e-phenyl aphezulu engeziwe enziwe nge-premium ayi-premium thermally stable silicone PSA.
3. Amabanga akhethekile acwebezelayo naphansi
Amamaki e-high-peel (isb., i-Dow 7385, ikhasi elijwayelekile >10N/25mm): Ukulayishwa kwe-resin ye-MQ ephezulu kunikeza amandla okuqala okuhle kakhulu okuthelwa kanye namandla okucwecwa, kodwa ngezindleko zokumelana nokushisa nokuzinza kokubumbana. Abonisa ukwehla okukhulu kwekhasi ngemva kokuguga futhi ajwayele ukusala ngenxa yokubola okushisayo kwe-resin. Sebenzisa kuphela izinhlelo zokusebenza ezishintshashintshayo zezinga lokushisa eliphansi.
Amabanga aphansi, amamaki efilimu avikelayo anokubumbana okuphezulu: Ukuminyana okuphezulu kwe-crosslink kunikeza ukusebenza kwekhasi okuzinzile nokuzinza okuhle kakhulu kokuguga, kodwa ukulinganisa kokuqala okuphansi. Ngemva kokuguga, ahlala ehlangene kodwa abe lukhuni, okunciphisa ukuhambisana nezindawo ezimbi.
I-Crosslinking Mechanism – Peroxide vs. Addition Cure (Same Methyl Base)
Ngisho nange-methyl polymer efanayo, indlela yokwelapha ishintsha kakhulu indlela yokuziphatha yokuguga.
1. Ukwelashwa nge-peroxide (isizukulwane sokuqala esivamile)
I-peroxide eyinsalela ibangela ukuhlangana okungalawuleki kwangemuva ngesikhathi sokuguga okunezinga lokushisa eliphezulu.
Ama-spikes amandla e-peel ekuqaleni, bese egoqa kakhulu.
Ukubumbana kuyenyuka isikhashana, kulandelwa ukufiphala nokubamba ukwehluleka kwamandla.
Ukuguga kwe-batch-to-batch akulungile.
2. Ukwelapheka (ukwelashwa nge-hydrosilylation)
Ikhambi alikhiqizi imikhiqizo; inethiwekhi ye-crosslink iyalawuleka kahle.
Izinguquko zezakhiwo zangemva kokuguga zilandela ithrendi yomugqa ebikezelwayo.
Ukugcinwa kwekhasi okuphakeme kakhulu nokuqina kokuhlangana uma kuqhathaniswa nokwakheka kwe-peroxide.
Isiqondiso Sokukhetha Ibanga
Isimo Sesevisi |
Ibanga Elinconyiwe |
Kungani |
Izinga lokushisa eliphakeme eliqhubekayo (>200°C), ikhasi elizinzile, izinsalela eziziro |
I-Addition-cured, high-phenyl (isb, i-Dow 7388, Q2-7406) |
>85% ukugcinwa kwekhasi, akukho embrittlement, >80% ebambe ukugcinwa kwamandla |
Ukushisa okuphezulu kwesikhashana esifushane, kuzwela izindleko |
Uhlobo lwe-methyl olujwayelekile, olulashiwe, oluphekiwe ngemuva kokubhaka (isb, 7657) |
Kuyamukeleka kodwa lindela ukuwohloka kwekhasi kanye nokuvuthwa okungenzeka emijikelezweni emide |
Kudingeka ikhasi lokuqala eliphezulu kakhulu, izinga lokushisa eliphansi kuphela |
Ibanga eliphezulu le-methyl |
Hhayi ngenxa yokushisa okuphezulu okuqhubekayo; lindela insalela ngemva kokuguga |
Ifilimu yokuzivikela, ukubumbana okuphezulu, i-tack ephansi |
Ibanga le-high-crosslink low-peel |
Ukuzinza okuhle kakhulu kokuguga kodwa kuqinile futhi kuhambisana kancane |
Isincomo se-Aokai PTFE : Kunoma iyiphi itheyiphu ye-PTFE ezobona amazinga okushisa aqhubekayo ngaphezu kuka-200°C, cacisa i-methylphenyl silicone PSA enwetshiwe. Izindleko zangaphambili ziphezulu, kodwa zivimbela ukwehluleka kwenkundla okubangelwa izinsalela zokunamathela noma ukulahlekelwa kwebhondi.
Isifinyezo - Ukufanisa Ibanga Le-Silicone PSA Nesidingo Esishisayo
I-silicone yohlobo lwe-Methyl PSA (ikakhulukazi eyelapha nge-peroxide) ifaneleka kuphela ukusetshenziswa kwezikhawu noma izinga lokushisa eliphansi. Ngemuva kwezinsuku eziyi-7 ku-250 ° C, lindela ukulahleka kwekhasi okungama-30-50% kanye nokuvela okungenzeka.
I-Methylphenyl (high-phenyl) abicah PSA igcina >85% amandla ekhasi nokuhlangana okuvumelana nezimo ngemva kokuguga okufanayo. Kuwukukhetha kwesevisi eqhubekayo engu-200-250°C.
Indlela ye-Crosslinking ibaluleke kakhulu: ukwelashwa kokwengeza (i-hydrosilylation) izinze kakhulu kunokwelapha nge-peroxide.
Amabanga anepeel ephezulu ahweba ngokuzinza kokuguga ukuze athathelwe izinyathelo zokuqala - zigweme ezinhlelweni ezishisayo.
Ngokufuna i-bonding yezinga eliphezulu lokushisa, i-Aokai PTFE isebenzisa ama-PSA e-methylphenyl silicone enziwe ngokwengeziwe. Singahlinzeka ngedatha yokugcinwa kwekhasi ngemva kuka-1000h ku-250°C uma siyicela.
Okuqukethwe kobuchwepheshe kuhlinzekwe ngu I-Jiangsu Aokai New Materials Technology Co., Ltd.
Ukuze uthole imininingwane yedatha yedatha yezobuchwepheshe nezixazululo zangokwezifiso ze-PTFE zezindwangu ezisezingeni lokushisa eliphezulu, amateyipu, amabhande anezikhala, nokuningi:
Ngokuhambisana nobungcweti nobuqotho, sihlinzeka ngezixazululo ezenziwe ngokwezifiso zokuma okukodwa kanye nezinsizakalo ezicabangelayo zangemuva kokuthengisa.
