Momwe Sungunula Flow Index Imakhudzira Magwiridwe Opaka Paufa a LDPE
The melt flow index (MI), yomwe imadziwikanso kuti melt flow rate (MFR), ndi chizindikiro chofunikira choyezera kusungunuka kwamadzimadzi a polyethylene LDPE zokutira ufa pansi pa kutentha kwapadera ndi kupanikizika. Mtengo wake umakhudza mwachindunji magwiridwe antchito, mawonekedwe opanga mafilimu, komanso mawonekedwe omaliza a zokutira. Zotsatirazi ndizomwe zimakhudzidwa ndi ndondomeko yosungunuka yosungunuka pazinthu za zokutira za LDPE:
1. Zimakhudza Kukonzekera Magwiridwe
Fluidity ndi Kupaka Mwachangu
Kukwera kwazomwe zimasungunuka, kumapangitsa kuti ufa wa LDPE ukhale wosungunuka.
- High MI (mwachitsanzo,> 20g / 10min): Ufa wosungunuka ndi wosavuta kufalikira, womwe ndi woyenera pazigawo zokhala ndi mawonekedwe ovuta, ziboliboli zakuya, kapena mipata yabwino (monga mapaipi ndi zigawo zooneka bwino). Ikhoza kudzaza mwamsanga mipata ndi kuchepetsa ❖ kuyanika kutayikira mfundo.
- Low MI (mwachitsanzo, <5g/10min): Kusungunuka kumakhala ndi kukhuthala kwakukulu komanso kusayenda bwino. Panthawi yophimba, kutentha kwakukulu kapena kupanikizika kumafunika; apo ayi, mavuto monga ❖ kuyanika osagwirizana ndi thovu ndi sachedwa kuchitika. Ndizoyeneranso ndege zosavuta kapena zofunikira zokutira wandiweyani (monga pamwamba pa mbale).
Kuchiritsa Kuthamanga ndi Kuchita Mwachangu
LDPE yokhala ndi MI yayikulu imazizira ndikuchiritsa mwachangu ikasungunuka, zomwe zimatha kufupikitsa nthawi yochiritsa pamzere wopanga ndikuwonjezeratput pa nthawi ya unit; MI yotsika imakonda kupaka utoto chifukwa cha kuchepa kofanana pakuzizira chifukwa cha kukhuthala kwakukulu, zomwe zimafuna nthawi yayitali yochiritsa.
2. Zokhudza Kuyika Mawonekedwe
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Kusalala ndi Kuwala: Kusungunuka kokhala ndi MI yayikulu kumakhala ndi madzi abwino. Pambuyo pakuphimba, imatha kuyenda ndikuyenda mwachibadwa, kupanga zokutira zosalala komanso zonyezimira, komanso kuchepetsa zolakwika monga peel lalanje ndi mapini; kusungunula ndi MI yotsika kumakhala kovuta kuyenda ndi msinkhu, ndipo chophimba pamwamba chimakhala chovuta kwambiri ndi kung'ung'udza pang'ono, ndipo ngakhale kugwedezeka (panthawi yophimba pamwamba) kungatheke.
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Makulidwe Ofanana: Mkulu wa MI ndi woyenera zokutira zoonda (mwachitsanzo, 10-50μm), ndipo makulidwe a yunifolomu amatha kupezeka powongolera nthawi yosungunuka; MI yotsika ndiyoyenera kwambiri zokutira zokhuthala (mwachitsanzo, 50-200μm), koma kuchuluka kwa zokutira kumafunika kuwongolera bwino, apo ayi kudzikundikira kwanuko kapena makulidwe osagwirizana kumakonda kuchitika chifukwa cha kusayenda bwino kwamadzi.
3. Zomwe Zimagwira pa Thupi la Zovala
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Kumamatira: Zovala za LDPE zokhala ndi MI sing'anga (mwachitsanzo, 5-20g / 10min) zimakhala zomatira bwino: kusungunula sikungalowemo mu pores ting'onoting'ono pamtunda wa gawo lapansi kuti apange mgwirizano wamakina, komanso sichidzayambitsa kulowetsedwa kwakukulu ndi kutayika chifukwa cha madzi amphamvu kwambiri (mkulu wa MI) kapena kugwirizana kosauka chifukwa cha kuchepa kwa madzi okwanira (ochepa MI).
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Kulimba ndi Kukaniza Kuvala: Chophimba cha LDPE chokhala ndi MI chochepa chimakhala ndi cholumikizira cholimba cha mamolekyulu, ndipo chophimbacho chimakhala ndi kuuma kwapamwamba komanso kukana kuvala bwino pambuyo pa kuzizira, komwe kuli koyenera kwa zochitika zokhala ndi zofunikira zazikulu pamakina (monga pansi ndi zida za zida); zokutira zokhala ndi MI yayikulu zimakhala ndi mamolekyu osasunthika, kuuma pang'ono, ndipo ndikosavuta kukanda, koma kumasinthasintha bwino.
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Kusinthasintha ndi Kukaniza Kwambiri: Chophimba cha LDPE chokhala ndi MI yapamwamba chimakhala ndi kusinthasintha kwabwinoko ndipo chimatha kupirira kusinthika pang'ono kwa gawo lapansi (monga kupindika ndi kugwedezeka) popanda kusweka, komwe kuli koyenera magawo opunduka mosavuta monga mapulasitiki ndi mapepala achitsulo; Chophimba chokhala ndi MI yotsika sichimasinthasintha bwino ndipo chimakonda kusweka ngati chakhudzidwa, koma chimakhala ndi mphamvu zochulukirapo pang'ono.
PECOAT® pangani melt flow index (MI) molingana ndi zomwe ziyenera kuphimbidwa.
4.Summary
The melt flow index ndi gawo lalikulu la zokutira za ufa wa LDPE. Posankha, ndikofunikira kufananiza mozama molingana ndi ukadaulo wopangira (monga njira yokutira, machiritso), mawonekedwe apansi panthaka, makulidwe okutira, ndi zofunikira pakuchita:
- Kwa mawonekedwe ovuta, zokutira zoonda, ndi zofunikira zowala kwambiri → mkulu MI (mwachitsanzo, 20-100g/10min);
- Pa zokutira wandiweyani, kuuma kwakukulu, ndi zofunika kuvala kukana → otsika MI (mwachitsanzo, 0.5-5g/10min);
- Pakumamatira koyenera komanso zochitika zapadziko lonse lapansi → sing'anga MI (mwachitsanzo, 5-20g/10min).
