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Abubuwan Dankowa na Hydroxypropyl Methyl Cellulose

Hydroxypropyl methylcelluloseHPMC) shi ne mara-ionic, ruwa mai narkewa cellulose gauraye ether.Siffar fari ce zuwa foda mai ɗan rawaya ko ɗan ƙaramin abu, mara ɗanɗano, mara wari, mara guba, tsayayyen sinadarai, kuma yana narkewa cikin ruwa don samar da ingantaccen bayani mai santsi, bayyananne da danko.Ɗaya daga cikin mahimman kaddarorin hydroxypropyl methylcellulose a aikace shine cewa yana ƙara danko na ruwa.Sakamakon thickening ya dogara da digiri na polymerization (DP) na samfurin, ƙaddamar da ether na cellulose a cikin maganin ruwa mai ruwa, yawan raguwa, da zafin jiki na bayani.Da sauran dalilai.

01

Nau'in ruwa na maganin ruwa na HPMC

Gabaɗaya, ana iya bayyana damuwa na ruwa a cikin kwararar shear a matsayin aiki na ƙimar shear ƒ(γ) kawai, idan dai bai dogara da lokaci ba.Dangane da nau'in ƒ(γ), ana iya raba ruwaye zuwa nau'ukan daban-daban, wato: Ruwan Newtonian, Dilatant fluids, ruwan pseudoplastic da ruwan roba na Bingham.

Cellulose ethers sun kasu kashi biyu: daya ba ionic cellulose ether da sauran shi ne ionic cellulose ether.Don rheology na waɗannan nau'ikan ethers na cellulose guda biyu.SC Naik et al.gudanar da wani m da kuma na yau da kullum nazarin kwatance a kan hydroxyethyl cellulose da sodium carboxymethyl cellulose mafita.Sakamakon ya nuna cewa duka hanyoyin da ba na ionic cellulose ether mafita da ionic cellulose ether mafita sun kasance pseudoplastic.Gudun ruwa, watau magudanar ruwa wanda ba na Newtonian ba, suna kusantar ruwan Newtonian kawai a cikin ƙarancin ƙima.A pseudoplasticity na hydroxypropyl methylcellulose bayani taka muhimmiyar rawa a aikace-aikace.Alal misali, lokacin da aka yi amfani da shi a cikin sutura, saboda halayen ɓacin rai na maganin ruwa na ruwa, dankon maganin yana raguwa tare da karuwar adadin shear, wanda ya dace da rarrabuwa iri-iri na barbashi pigment, kuma yana ƙara yawan ruwa na rufin. .Tasirin yana da girma sosai;yayin da yake hutawa, danko na maganin yana da girma, wanda ya hana ƙaddamar da ƙwayoyin pigment a cikin sutura.

02

Hanyar Gwajin Dankowar HPMC

Wani muhimmin alama don auna tasirin kauri na hydroxypropyl methylcellulose shine bayyanar danko na maganin ruwa.Hanyoyin aunawa na bayyanar danko yawanci sun haɗa da hanyar dankowar capillary, hanyar jujjuyawa danko da faɗuwar hanyar ɗanɗanon ƙwallon.

inda: shine bayyanannen danko, mPa s;K shine madaidaicin viscometer;d shine yawancin samfurin bayani a 20/20 ° C;t shine lokacin da maganin zai wuce ta ɓangaren sama na viscometer zuwa alamar ƙasa, s;Lokacin da daidaitaccen mai ke gudana ta cikin viscometer ana aunawa.

Koyaya, hanyar auna ta capillary viscometer ya fi damuwa.Abubuwan da ke tattare da ethers na cellulose da yawa suna da wuyar tantancewa ta amfani da viscometer capillary saboda waɗannan mafita sun ƙunshi adadin abubuwan da ba za a iya narkewa ba waɗanda ake ganowa kawai lokacin da aka toshe viscometer capillary.Sabili da haka, yawancin masana'antun suna amfani da viscometers na juyawa don sarrafa ingancin hydroxypropyl methylcellulose.Ana amfani da viscometers na Brookfield a ƙasashen waje, kuma ana amfani da viscometer na NDJ a China.

03

Abubuwan da ke tasiri na dankowar HPMC

3.1 Alaka tare da matakin tarawa

Lokacin da wasu sigogi suka kasance ba su canza ba, danko na hydroxypropyl methylcellulose bayani yana daidai da digiri na polymerization (DP) ko nauyin kwayoyin halitta ko tsayin sarkar kwayoyin halitta, kuma yana ƙaruwa tare da karuwa da digiri na polymerization.Wannan tasiri ya fi bayyana a cikin yanayin ƙananan ƙwayar ƙwayar cuta fiye da yanayin da ake ciki na polymerization.

3.2 Dangantaka tsakanin danko da maida hankali

Dankowar hydroxypropyl methylcellulose yana ƙaruwa tare da haɓaka haɓakar samfurin a cikin maganin ruwa.Ko da ƙananan sauye-sauyen maida hankali zai haifar da babban canji a cikin danko.Tare da danko mara kyau na hydroxypropyl methylcellulose Sakamakon canji na maida hankali a kan danko na maganin yana da yawa.

3.3 Dangantaka tsakanin danko da ƙimar ƙarfi

Hydroxypropyl methylcellulose bayani mai ruwa-ruwa yana da mallakar tsirin tsiro.Hydroxypropyl methylcellulose na danko daban-daban an shirya shi cikin maganin ruwa na 2%, kuma an auna dankon sa a nau'ikan juzu'i daban-daban bi da bi.Sakamakon yana kamar haka Kamar yadda aka nuna a cikin adadi.A ƙananan ƙarancin ƙarfi, dankowar maganin hydroxypropyl methylcellulose bai canza sosai ba.Tare da haɓakar ƙimar shear, danko na hydroxypropyl methylcellulose bayani tare da mafi girman danko na ƙima ya ragu sosai a fili, yayin da maganin tare da ƙananan danko bai ragu ba a fili.

3.4 Dangantaka tsakanin danko da zafin jiki

Dankowar maganin hydroxypropyl methylcellulose yana da matukar tasiri ta yanayin zafi.Yayin da zafin jiki ya karu, dankon maganin yana raguwa.Kamar yadda aka nuna a cikin adadi, an shirya shi a cikin wani bayani mai ruwa tare da maida hankali na 2%, kuma ana auna canjin danko tare da karuwar zafin jiki.

3.5 Wasu abubuwa masu tasiri

Dankowar maganin ruwa na hydroxypropyl methylcellulose shima yana shafar abubuwan da ke cikin maganin, ƙimar pH na maganin, da lalata ƙwayoyin cuta.Yawancin lokaci, don samun kyakkyawan aikin danko ko rage farashin amfani, ya zama dole don ƙara gyare-gyaren rheology, kamar yumbu, yumbu da aka gyara, foda polymer, sitaci ether da aliphatic copolymer, zuwa maganin ruwa na hydroxypropyl methylcellulose., da kuma electrolytes irin su chloride, bromide, phosphate, nitrate, da dai sauransu kuma za a iya karawa a cikin maganin ruwa.Wadannan additives ba kawai za su shafi kaddarorin danko na maganin ruwa ba, amma kuma suna shafar sauran kaddarorin aikace-aikacen hydroxypropyl methylcellulose kamar riƙe ruwa., sag juriya, da dai sauransu.

A danko na ruwa bayani na hydroxypropyl methylcellulose kusan ba zai shafi acid da alkali, kuma shi ne gaba ɗaya barga a cikin kewayon 3 zuwa 11. Yana iya jure wani adadin rauni acid, kamar formic acid, acetic acid, phosphoric acid. , boric acid, citric acid, da dai sauransu. Duk da haka, mai da hankali acid zai rage danko.Amma caustic soda, potassium hydroxide, lemun tsami ruwan lemun tsami, da dai sauransu suna da kadan tasiri a kan shi.Idan aka kwatanta da sauran cellulose ethers, hydroxypropyl methylcellulose ruwa bayani yana da kyau antimicrobial kwanciyar hankali, babban dalilin shi ne cewa hydroxypropyl methylcellulose yana da hydrophobic kungiyoyin tare da babban mataki na maye da kuma steric hana kungiyoyin Duk da haka, tun da canji dauki yawanci ba uniform, da unsabstituted anhydroglucose unit. Mafi sauƙaƙan ƙwayoyin cuta suna lalacewa, wanda ke haifar da lalacewar ƙwayoyin ether na cellulose da scission sarkar.Ayyukan shine cewa bayyanar danko na maganin ruwa yana raguwa.Idan ya zama dole don adana ruwa mai ruwa na hydroxypropyl methylcellulose na dogon lokaci, ana bada shawara don ƙara adadin adadin maganin antifungal don kada danko ya canza sosai.Lokacin zabar magungunan rigakafin fungal, masu kiyayewa ko fungicides, ya kamata ku kula da aminci, kuma zaɓi samfuran da ba su da guba ga jikin ɗan adam, suna da kaddarorin da ba su da wari, kamar DOW Chem's AMICAL fungicides, CANGUARD64 preservatives, FUELSAVER kwayoyin agents. da sauran kayayyakin.zai iya taka rawar da ta dace.


Lokacin aikawa: Oktoba-20-2022