Hydroxypropyl methylcellulose waa nooc ka mid ah cellulose aan ionic ahayn oo isku qasan. Si ka duwan ionic methyl carboxymethyl cellulose ether qasan, kuma falceliso biraha culus. Sababtoo ah saamiga kala duwan ee maadada methoxyl iyo maadada hydroxypropyl ee hydroxypropyl methylcellulose iyo viscosities kala duwan, waxaa jira noocyo badan oo leh sifooyin kala duwan, tusaale ahaan, maadada methoxyl sare iyo maadada hydroxypropyl hoose Waxqabadkeedu wuxuu ku dhow yahay kan methyl cellulose, halka kan hoose Maadada methoxyl iyo ka kooban hydroxypropyl sare waxay ku dhowdahay ta hydroxypropyl methyl cellulose. Si kastaba ha noqotee, nooc kasta oo kala duwan, inkasta oo kaliya qadar yar oo ah kooxda hydroxypropyl ama qadar yar oo ah kooxda methoxyl ay ku jiraan, waxaa jira kala duwanaansho weyn oo ku milmay dareerayaasha organic ama heerkulka flocculation ee xalalka aqueous.
(1) Sifooyinka milmay ee hydroxypropyl methylcellulose
①Solubility of hydroxypropyl methylcellulose biyaha Hydroxypropyl methylcellulose dhab ahaantii waa nooc ka mid ah methylcellulose modified by propylene oxide (methoxypropylene), sidaas darteed waxa ay weli leedahay sifooyin la mid ah sida methyl cellulose Cellulose waxa uu leeyahay sifooyin la mid ah milanka biyaha qabow iyo biyo kulul. Si kastaba ha ahaatee, sababtoo ah kooxda hydroxypropyl ee la bedelay, heerkulka gelation ee biyaha kulul ayaa aad uga sarreeya kan methyl cellulose. Tusaale ahaan, viscosity of hydroxypropyl methylcellulose xal aqueous oo leh 2% methoxy content beddelka shahaadada DS=0.73 iyo maadada hydroxypropyl MS=0.46 waa 500mpa·s at 20°C methyl cellulose isla heerkulku waa qiyaastii 55°C. Marka laga hadlayo milanka biyaha, sidoo kale si weyn ayaa loo hagaajiyay. Tusaale ahaan, hydroxypropyl methylcellulose oo la burburiyay (qaab granular 0.2 ~ 0.5mm at 20 ° C leh 4% viscosity xal aqueous of 2pa•s waxaa laga iibsan karaa heerkulka qolka, si fudud ayay ugu milmay biyaha iyada oo aan qaboojin.
②Malka hydroxypropyl methylcellulose ee dareerayaasha organic. Alaabooyinka ka sarreeya 2.1, viscosity hydroxypropyl methylcellulose-sare oo ka kooban hydroxypropyl MS = 1.5 ~ 1.8 iyo methoxy DS = 0.2 ~ 1.0, oo leh wadarta guud ee beddelka ka sarreeya 1.8, waxay ku milmi kartaa methanol anhydrous iyo xalalka ethanol Dhexdhexaad, iyo thermoplastic iyo biyo-soluble . Waxa kale oo ay ku milmi kartaa hydrocarbons koloriin leh sida methylene chloride iyo chloroform, iyo dareerayaasha organic sida acetone, isopropanol iyo diacetone khamriga. Ku milmaynteeda dareerayaasha organic waxay ka fiican tahay milanka biyaha.
(2) Sababaha saameeya viscosity of hydroxypropyl methylcellulose Go'aaminta viscosity caadiga ah ee hydroxypropyl methylcellulose waa la mid ah ethers kale cellulose, waxaana lagu qiyaasaa 20 ° C leh 2% aqueous xal sida caadiga ah. Viscosity ee alaabta la mid ah waxay kordhisaa kororka feejignaanta. Alaabooyinka leh miisaan kala duwan oo unugyo isku mid ah, badeecada miisaankeedu weyn yahay waxay leedahay viscosity sare. Xidhiidhka ay la leedahay heerkulka ayaa la mid ah kan methyl cellulose. Marka heerkulku kor u kaco, viscosity-ku wuxuu bilaabmaa inuu hoos u dhaco, laakiin marka uu gaaro heerkul gaar ah, viscosity-ku si lama filaan ah ayuu u kacayaa waxaana soo baxa gelitaanka. Heerkulka jel ee alaabooyinka viscosity-yar ayaa sarreeya. waa sare Its dhibic jel ma aha oo kaliya la xidhiidha viscosity of ether, laakiin sidoo kale la xidhiidha saamiga ka kooban ee kooxda metoxyl iyo kooxda hydroxypropyl ee ether iyo cabbirka wadarta shahaadada beddelka. Waa in la ogaadaa in hydroxypropyl methylcellulose sidoo kale waa pseudoplastic, iyo xalkeedu waa ku xasiloon yahay heerkulka qolka iyada oo aan wax nabaad-guur ah ee viscosity marka laga reebo suurtagalnimada hoos u enzymatic.
(3) Dulqaadka milixda ee hydroxypropyl methylcellulose Maadaama hydroxypropyl methylcellulose uu yahay ether-ka aan-ionic ahayn, ma ionize warbaahinta biyaha, si ka duwan ethers cellulose kale ee ionic, Tusaale ahaan, karboxymethyl cellulose waxay la falgashaa ions birta culus waxayna soo saartaa xalka. Cusbada guud sida chloride, bromide, fosfate, nitrate, iwm. ma soo da'ayaan marka lagu daro xalkeeda aqueous. Si kastaba ha ahaatee, ku darida milixdu waxay xoogaa saameyn ah ku leedahay heerkulka qulqulka ee xalkeeda aqueous. Marka xoogga milixdu kordho, heerkulka jelku wuu yaraadaa. Marka fiirsashada milixdu ay ka hooseyso barta qulqulka, mawjadaha xalka ayaa u muuqda inuu kordho. Sidaa darteed, xaddi milix ah ayaa lagu daraa. , Codsiga, waxay ku gaari kartaa saameyn dhumuc dhaqaale ahaan. Sidaa darteed, codsiyada qaarkood, way fiicantahay in la isticmaalo isku dhafka ether cellulose iyo milix marka loo eego xoojinta sare ee xalalka etherka si loo gaaro saameynta dhumucda.
(4) Hydroxypropyl methylcellulose acid iyo caabbinta alkali Hydroxypropyl methylcellulose guud ahaan waa mid degan asiidhyada iyo alkaliska, mana saamayso inta u dhaxaysa pH 2 ~ 12. Waxay u adkeysan kartaa xaddi gaar ah oo asiidh iftiin ah, sida formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, iwm. Laakin acid-kooxdu waxay saameyn ku leedahay yaraynta viscosity. Alkalis sida soodhaha caustic, potash caustic iyo biyaha lime wax saameyn ah kuma laha, laakiin waxay kordhin karaan viscosity ee xalka, ka dibna si tartiib ah u yareynaya.
(5) Waafaqsanaanta hydroxypropyl methylcellulose Hydroxypropyl methylcellulose xalka waxaa lagu qasi karaa xeryahooda polymer-ka biyaha-milmi kara si loo sameeyo xal labis ah oo hufan oo leh viscosity sare. Xeryahooda polymer waxaa ka mid ah polyetylen glycol, polyvinyl acetate, polysilicon, polymethylvinylsiloxane, hydroxyethyl cellulose, iyo methyl cellulose. Iskudhisyada molecular sare ee dabiiciga ah sida cirridka carabiga, xanjada digirta ayaxa, xanjada karaya, iwm sidoo kale waxay leeyihiin waafaqid wanaagsan xalkeeda. Hydroxypropyl methylcellulose sidoo kale waxaa lagu qasi karaa mannitol ester ama sorbitol ester of stearic acid ama palmitic acid, sidoo kale waxaa lagu qasi karaa glycerin, sorbitol iyo mannitol, xeryahoodana waxaa loo isticmaali karaa sida hydroxypropyl methylcellulose Plasticizer for cellulose.
(6) Ethers-cellulose-ka biyaha-milmi kara ee hydroxypropyl methylcellulose waxay samayn karaan isku-tallaabta dusha sare leh aldehydes, si ay kuwan biyaha-milmi leh ay u soo baxaan xalka oo ay noqdaan kuwo aan milmin biyaha. Aldehydes ee ka dhigaya hydroxypropyl methylcellulose aan la karin karin waxaa ka mid ah formaldehyde, glyoxal, succinic aldehyde, adipaldehyde, iwm. Marka la isticmaalayo formaldehyde, fiiro gaar ah waa in la siiyaa qiimaha pH ee xalka, oo ka mid ah glioxal falcelin degdeg ah , sidaas darteed glioxal waxaa caadi ahaan loo isticmaalaa sida crosslink. wakiilka wax soo saarka warshadaha. Qadarka wakiilka noocan oo kale ah ee isku-dhafan ee xalka waa 0.2% ~ 10% miisaanka ether, doorbidaya 7% ~ 10%, tusaale ahaan, 3.3% ~ 6% glioxal ayaa ah kan ugu habboon. Guud ahaan, heerkulka daawaynta waa 0 ~ 30 ℃, iyo waqti waa 1 ~ 120min. Dareen-celinta isku-xiran waxay u baahan tahay in lagu sameeyo xaaladaha acidic. Guud ahaan, xalka ayaa marka hore lagu daraa asiidh xooggan oo aan dabiici ahayn ama karboksylic acid organic si loo hagaajiyo pH ee xalka ilaa 2 ~ 6, oo doorbidan inta u dhaxaysa 4 ~ 6, ka dibna ku dar aldehydes si loo fuliyo falcelinta isku-xiran. Aashitada la isticmaalay ayaa leh hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid ama citric acid iwm. Aashitada iyo aldehyde ayaa sidoo kale lagu dari karaa isku mar si loogu oggolaado xalka inuu maro fal-celin isku-xiran oo dhexda u ah qiyaasta pH ee la doonayo. Dareen-celintan waxaa badanaa loo isticmaalaa habka daaweynta ugu dambeysa ee habka diyaarinta ethers cellulose. Ka dib markii ether-ka cellulose uu yahay mid aan la milmi karin, way ku habboon tahay in la isticmaalo
20 ~ 25℃ biyaha lagu dhaqo iyo sifaynta. Marka badeecada la isticmaalo, walxaha alkaline ayaa lagu dari karaa xalka badeecada si loo hagaajiyo pH ee xalka si ay u noqoto alkaline, badeecaduna waxay ku milmi doontaa xalka si dhakhso ah. Habkani wuxuu sidoo kale lagu dabaqi karaa daaweynta filimka ka dib marka xalalka etherka cellulose laga sameeyo filim si looga dhigo filim aan la milmin.
(7) Caabbinta Enzyme ee hydroxypropyl methylcellulose Aragti ahaan, soosaarayaasha cellulose, sida koox si adag ugu xidhan koox kasta oo anhydroglucose ah, uma nugulna nabaad guurka microbial, laakiin dhab ahaantii, marka qiimaha beddelka ee alaabta la dhammeeyey ka badan tahay 1, waxay noqon doontaa. Sidoo kale waxaa hoos u dhigaya enzymes, taas oo macnaheedu yahay in heerka beddelka koox kasta ee silsiladda cellulose aysan ahayn mid la mid ah. ku filan, iyo microorganismsku way baabi'i karaan kooxda anhydroglucose aan la bedelin. Sonkorta ayaa samaysma oo la nuugo sida nafaqeeyayaalka noolaha. Sidaa darteed, haddii heerka beddelka etherification ee cellulose uu kordho, iska caabinta enzymatic nabaad guurka etherka cellulose ayaa sidoo kale kordhin doona. Sida laga soo xigtay warbixinnada, xaaladaha la xakameeyey, natiijooyinka hydrolysis ee enzymes, haraaga haraaga ee hydroxypropyl methylcellulose (DS=1.9) waa 13.2%, methylcellulose (DS=1.83) waa 7.3%, methylcellulose (DS=1.66) waa 3.8%, iyo hydroxyethyl cellulose waa 1.7%. Waxaa la arki karaa in hydroxypropyl methylcellulose uu leeyahay awood xoog leh oo anti-enzyme ah. Sidaa darteed, iska caabbinta enzyme aad u fiican ee hydroxypropyl methylcellulose, oo ay weheliso kala-baxsanaanteeda wanaagsan, dhumucdeeda iyo sameynta filimada, ayaa loo isticmaalaa daaha-biyoodka-emulsion-ka, iwm, iyo guud ahaan uma baahna in lagu daro waxyaabaha ilaaliya. Si kastaba ha noqotee, kaydinta muddada dheer ee xalka ama wasakheynta suurtagalka ah ee ka imanaysa dibadda, ilaalinta ayaa lagu dari karaa taxadar ahaan, doorashadana waxaa lagu go'aamin karaa iyadoo loo eegayo shuruudaha ugu dambeeya ee xalka. Phenylmercuric acetate iyo manganese fluorosilicate waa ilaalin wax ku ool ah, laakiin dhammaantood waxay leeyihiin sunta, dareenka waa in la bixiyaa hawlgalka. Guud ahaan, 1 ~ 5mg of phenylmercury acetate ayaa lagu dari karaa xalka halkii litir ee qiyaasta.
(8) Waxqabadka filimka hydroxypropyl methylcellulose Hydroxypropyl methylcellulose wuxuu leeyahay sifooyin filim-samayn heersare ah. Xalka aqueous ama dareeraha dareeraha organic waxaa lagu dahaadhay saxan galaas, oo waxay noqotaa mid xor ah qalajinta ka dib. Midab, filim hufan oo adag. Waxay leedahay iska caabin qoyaan wanaagsan waxayna ku sii adkaysataa heerkulka sare. Haddii balaastikada hygroscopic lagu daro, dhererkeeda iyo dabacsanaanteeda waa la wanaajin karaa. Marka la eego hagaajinta dabacsanaanta, balaastikada sida glycerin iyo sorbitol ayaa ah kuwa ugu habboon. Guud ahaan, xoojinta xalku waa 2% ~ 3%, iyo qadarka balaastikada waa 10% ~ 20% eter cellulose. Haddii waxa ku jira balaastiiste aad u badan tahay, fuuqbaxa kolloidal waxay ku dhici doontaa qoyaan badan. Xoogga jilicsan ee filimka lagu daray balaastiigga ayaa aad uga weyn kan aan lahayn balaastiig, waxayna kordhisaa korodhka qadarka lagu daray. Sida hygroscopicity ee filimka, waxay sidoo kale kordhisaa kordhinta qadarka balaastikada.
Waqtiga boostada: Dec-20-2022