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HPMC ee Dahaarka Filimka

HPMC ee Dahaarka Filimka

HPMC eeDahaarka filimku waa farsamada samaynta filim khafiif ah oo polymer ah oo ka sarreeya diyaarinta adag. Tusaale ahaan, lakabka walxaha polymer-ka ah ayaa si isku mid ah loogu buufiyaa dusha sare ee xaashida caadiga ah iyadoo la buufinayo habka lagu buufiyo si loo sameeyo lakabka filim caag ah oo dhowr microns ah, si loo gaaro saameynta la rabo. Samaynta lakabkan filimka ka baxsan kiniinka ayaa ah in hal kiniin ah uu ku dheggan yahay walxaha dahaarka polymer ka dib marka uu dhex maro aagga buufinta, ka dibna uu helo qaybta xigta ee alaabta daahan ka dib qalajinta. Ka dib markii lagu dhajiyo iyo qalajinta soo noqnoqda, daboolka ayaa la dhammeeyaa ilaa dhammaan dusha sare ee diyaarinta si buuxda loo daboolo. Daahan filimku waa filim joogto ah, dhumucdiisuna waxay u dhaxaysaa 8 ilaa 100 microns, heer go'an oo barti iyo dabacsanaan, si adag ugu dheggan dusha sare ee xudunta.

Sannadkii 1954-kii, Abbott wuxuu soo saaray dufcaddii ugu horreysay ee xaashiyo filim ganacsi ahaan la heli karo, tan iyo markaas, iyada oo la sii wanaajiyey iyo dhammaystirka qalabka wax soo saarka iyo tignoolajiyada, agabka filimka polymer ayaa la sii daayay, si tignoolajiyada dahaadhka filimka si dhakhso ah loo horumariyo. Ma aha oo kaliya noocyada kala duwan, tirada iyo tayada wakiilada midabka midabka ayaa si degdeg ah u kordhay, laakiin sidoo kale noocyada, foomamka iyo sifooyinka tignoolajiyada dahaarka, qalabka dahaarka iyo filimka daahan iyo sidoo kale daahan ee kiniinka TCM ayaa si weyn loo horumariyay. Sidaa darteed, codsiga tignoolajiyada daahan filimku waxay noqotay baahida iyo isbeddelka horumarinta shirkadaha dawooyinka si loo hagaajiyo tayada wax soo saarka.

Isticmaalka hore ee daahan aflaanta walxaha samaynta, waxaa jira tiro badan oo alaabooyin ah oo isticmaalaya HPMChydroxypropyl methylcellulosesida walxaha Membrane. Waa daahirintuHPMCcellulose ka soo suuf lint ama saxarka alwaax, iyo sodium hydroxide xal si ay u muujiyaan bararka cellulose alkali, ka dibna la daawaynta chloromethane iyo propylene oxide si aad u hesho methyl hydroxypropyl cellulose etherHPMC, sheyga si looga saaro wasakhda ka dib qalajinta, burburinta, baakadaha. Guud ahaan, viscosity hoose HPMC waxa loo isticmaalaa sidiifilimwax daahan, iyo 2% ~ 10% xal waxaa loo isticmaalaa xal daahan. Khasaaraha ayaa ah in viscosity-ku aad u weyn yahay iyo ballaarintu aad u xoog badan tahay.

Jiilka labaad ee walxaha samaynta filimku waa khamriga polyvinyl (PVA). Khamriga Polyvinyl waxaa sameeyay alkolysis of polyvinyl acetate. Cutubyada soo noqnoqda khamriga Vinyl looma isticmaali karo falcelin ahaan sababtoo ah ma buuxinayaan tirada iyo nadiifnimada looga baahan yahay polymerization. In methanol, ethanol ama ethanol iyo methyl acetate xal isku dhafan oo leh birta alkali ama inorganic acid sida kicinta, hydrolysis waa degdeg ah.

PVA waxaa si weyn loogu isticmaalaa daahan filimka. Sababtoo ah waxay ku milmi karin biyaha heerkulka qolka, guud ahaan waxaa lagu dahaadhay 20% daadinta biyaha. Uumiga biyaha iyo qulqulka oksijiinta ee PVA way ka hooseeyaan HPMC iyo EC, markaa awoodda xannibaadda uumiga biyaha iyo ogsijiinta ayaa ka xoog badan, taas oo si fiican u ilaalin karta xudunta chip-ka.

Plasticizer waxaa loola jeedaa shay kordhin kara caagagga walxaha samaynta filimada. Qaar ka mid ah qalabka samaynta filimku waxay beddelaan sifooyinkooda jireed ka dib marka heerkulku hoos u dhaco, dhaqdhaqaaqa makromolecules-koodu wuu yaraadaa, taasoo ka dhigaysa dahaarka mid adag oo jajaban, la'aanta dabacsanaanta lagama maarmaanka ah, oo sidaas fudud u jabin. Balaastiiste ayaa lagu daray si loo dhimo heerkulka kala-guurka galaaska (Tg) loona kordhiyo dabacsanaanta dahaarka. Balaastiijiyeyaasha sida caadiga ah loo isticmaalo waa polymers amorphous leh oo miisaankoodu aad u weyn yahay iyo xiriir xoog leh oo leh walxaha filim samaynta. Balaastiigga aan la milmi karin waxay ka caawisaa in la yareeyo qulqulka daboolka, sidaas darteed kordhinta xasilloonida diyaarinta.

 

Waxaa guud ahaan la rumeysan yahay in habka balaastiigga uu yahay in molecules balaastikisku ay ku dhex jiraan silsiladda polymer, kaas oo xannibaya isdhexgalka u dhexeeya molecules polymer ilaa xad. Isdhexgalka ayaa sahlan marka isdhexgalka polymer-plasticizer uu ka xoog badan yahay isdhexgalka polymer-plasticizer. Sidaa darteed, fursadaha qaybaha polymer-ka si ay u guuraan waa la kordhiyaa.

Jiilka saddexaad ee walxaha samaynta filimku waa caagadeeyaha habka kiimikaad ee lagu tallaalay filimka sameynta walxaha polymer

Tusaale ahaan, filimka hal-abuurka leh ee samaynta walxaha Kollicoat® IR ee ay soo bandhigtay BASF ayaa ah in PEG si kiimiko ah loogu tallaalay silsiladda dheer ee PVA polymer iyada oo aan lagu darin balaastiig, si ay uga fogaato socdaalka harada ka dib dahaadhka.


Waqtiga boostada: Dec-23-2023
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