HPMC ya Kupaka Mafilimu

HPMC kwaKuphimba filimu ndi njira yopangira filimu yopyapyala ya polima pakukonzekera kolimba. Mwachitsanzo, wosanjikiza khola polima zakuthupi ndi sprayed uniformly padziko chigwa ndi kupopera mbewu mankhwalawa njira kupanga pulasitiki filimu wosanjikiza angapo microns wandiweyani, kuti tikwaniritse kufunika kwenikweni. Mapangidwe a filimuyi kunja kwa piritsi ndikuti piritsi limodzi limamatira kuzinthu zokutira za polima pambuyo podutsa malo opopera, ndiyeno amalandira gawo lotsatira la zinthu zokutira pambuyo poyanika. Pambuyo pophatikizana mobwerezabwereza ndi kuyanika, kuphimba kumatsirizidwa mpaka pamwamba pa kukonzekera kutsekedwa kwathunthu. Kupaka filimu ndi filimu yosalekeza, makulidwe ambiri pakati pa 8 mpaka 100 microns, mlingo wina wa elasticity ndi kusinthasintha, kumamatira pamwamba pa pachimake.

Mu 1954, Abbott anapanga gulu loyamba la mapepala opanga mafilimu omwe amapezeka pamalonda, kuyambira nthawi imeneyo, ndi kupititsa patsogolo kosalekeza ndi ungwiro wa zipangizo zopangira ndi teknoloji, zida za filimu za polima zatulutsidwa, kotero kuti teknoloji yophimba filimu yapangidwa mofulumira. Osati kokha mitundu yosiyanasiyana, kuchuluka ndi ubwino wa opangira utoto wamtundu wawonjezeka mofulumira, komanso mitundu, mawonekedwe ndi makhalidwe a teknoloji yophimba, zipangizo zophimba ndi filimu yophimba komanso kupaka mapiritsi a TCM apangidwa kwambiri. Chifukwa chake, kugwiritsa ntchito ukadaulo wopaka filimu kwakhala kufunikira ndi chitukuko chamakampani opanga mankhwala kuti apititse patsogolo malonda.

Kugwiritsa ntchito koyambirira pakupanga filimu yokutira filimu, pali zinthu zambiri zomwe zimagwiritsa ntchito HPMChydroxypropyl methylcellulosemonga ma membrane. Ndiko kuyeretsedwaMtengo wa HPMCmapadi kuchokera thonje lint kapena matabwa zamkati, ndi sodium hydroxide njira kusonyeza kutupa kwa mapadi alkali, ndiyeno ndi chloromethane ndi propylene okusayidi mankhwala kupeza methyl hydroxypropyl mapadi efa.Mtengo wa HPMC, mankhwala kuchotsa zonyansa pambuyo kuyanika, kuphwanya, kulongedza. Nthawi zambiri, otsika mamasukidwe akayendedwe HPMC ntchito ngatikanemazokutira zakuthupi, ndipo 2% ~ 10% yankho limagwiritsidwa ntchito ngati yankho lopaka. Choyipa ndichakuti mamasukidwe akayendedwe ndi akulu kwambiri ndipo kukulitsa kumakhala kolimba kwambiri.

M'badwo wachiwiri wa zinthu zopangira mafilimu ndi polyvinyl mowa (PVA). Mowa wa polyvinyl umapangidwa ndi alcoholysis ya polyvinyl acetate. Vinyl mowa wobwereza mayunitsi sangagwiritsidwe ntchito ngati reactants chifukwa samakwaniritsa kuchuluka ndi kuyera komwe kumafunikira polima. Mu methanol, ethanol kapena ethanol ndi methyl acetate njira yosakanikirana ndi zitsulo zamchere kapena asidi osakhazikika monga chothandizira, hydrolysis imathamanga.

PVA imagwiritsidwa ntchito kwambiri popaka filimu. Chifukwa sichisungunuka m'madzi otentha, nthawi zambiri imakutidwa ndi 20% kumwazikana kwamadzi. Mpweya wamadzi ndi mpweya wa okosijeni wa PVA ndi wotsika kuposa HPMC ndi EC, kotero kutsekereza mphamvu ya nthunzi yamadzi ndi okosijeni ndi yamphamvu, yomwe ingateteze bwino chip core.

Plasticizer amatanthauza zinthu zomwe zimatha kukulitsa pulasitiki yazinthu zopangira filimu. Zida zina zopangira filimu zimasintha mawonekedwe awo a thupi pambuyo pa kutentha kwachepa, ndipo kuyenda kwa macromolecules awo kumakhala kochepa, kumapangitsa kuti chophimbacho chikhale cholimba komanso chosasunthika, chosowa kusinthasintha koyenera, motero n'kosavuta kusweka. Plasticizer idawonjezeredwa kuti muchepetse kutentha kwa magalasi (Tg) ndikuwonjezera kusinthasintha kwa zokutira. Ma plasticizer omwe amagwiritsidwa ntchito kwambiri ndi ma polima amorphous okhala ndi kulemera kwakukulu kwa mamolekyulu komanso kuyanjana kwambiri ndi zida zopangira mafilimu. Pulasitiki yosasungunuka imathandiza kuchepetsa kutsekemera kwa zokutira, motero kumawonjezera kukhazikika kwa kukonzekera.

Amakhulupirira kuti makina a plasticizer ndikuti mamolekyu a plasticizer amalowetsedwa mu unyolo wa polima, womwe umalepheretsa kulumikizana pakati pa mamolekyu a polima kwambiri. Kuyanjana kumakhala kosavuta pamene kuyanjana kwa polima-pulasitiki kumakhala kolimba kuposa kuyanjana kwa polima-pulasitiki. Chifukwa chake, mwayi woti magawo a polima asamuke akuwonjezeka.

M'badwo wachitatu wa filimu kupanga zipangizo ndi plasticizer ndi mankhwala njira kumtengowo mu filimu kupanga zinthu polima

Mwachitsanzo, zinthu zatsopano zopangira filimu Kollicoat® IR yoyambitsidwa ndi BASF ndikuti PEG imalumikizidwa ndi mankhwala ku unyolo wautali wa PVA polima popanda kuwonjezera pulasitiki, kotero imatha kupeŵa kusuntha kwa nyanja pambuyo popaka.