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I-Viscosity Properties ye-Hydroxypropyl Methyl Cellulose

IHydroxypropyl methylcellulose (I-HPMC) i-ether engeyona i-ionic, i-cellulose encibilika emanzini exubile.Ukubukeka kumhlophe kuya kokuphuzi kancane noma impahla eyimbudumbudu, ayinambitheki, ayinaphunga, ayinobuthi, azinzile kumakhemikhali, futhi incibilika emanzini ukuze kwakhe isixazululo esibushelelezi, esisobala nesibonakalayo.Enye yezinto ezibaluleke kakhulu ze-hydroxypropyl methylcellulose ekusetshenzisweni ukuthi yandisa i-viscosity yoketshezi.Umphumela wokujiya uncike ezingeni le-polymerization (DP) lomkhiqizo, ukugcwala kwe-cellulose ether esixazululweni esinamanzi, izinga lokugunda, kanye nezinga lokushisa lesixazululo.Nezinye izici.

01

Uhlobo oluwuketshezi lwesisombululo samanzi se-HPMC

Ngokuvamile, ukucindezeleka koketshezi ekugelezeni kwe-shear kungavezwa njengomsebenzi wezinga lokugunda kuphela ƒ(γ), inqobo nje uma lingancikile esikhathini.Ngokuya ngohlobo lwe-ƒ(γ), uketshezi lungahlukaniswa lube izinhlobo ezahlukene, okuyilezi: Uketshezi lwe-Newtonian, uketshezi olunwebekayo, uketshezi lwe-pseudoplastic kanye noketshezi lwepulasitiki lwe-Bingham.

Ama-cellulose ether ahlukaniswe abe izigaba ezimbili: eyodwa i-non-ionic cellulose ether kanti enye i-ionic cellulose ether.Ukuze uthole i-rheology yalezi zinhlobo ezimbili ze-cellulose ethers.SC Naik et al.yenze ucwaningo olunzulu noluhlelekile lokuqhathanisa nge-hydroxyethyl cellulose kanye nezixazululo ze-sodium carboxymethyl cellulose.Imiphumela yabonisa ukuthi kokubili izixazululo ze-non-ionic cellulose ether kanye nezixazululo ze-ionic cellulose ether kwakuyi-pseudoplastic.Ukugeleza, okungukuthi ukugeleza okungekona okwe-Newtonian, kusondela oketshezini lwe-Newtonian kuphela ekugxilweni okuphansi kakhulu.I-pseudoplasticity yesisombululo se-hydroxypropyl methylcellulose idlala indima ebalulekile ekusetshenzisweni.Isibonelo, uma isetshenziswa emigqeni, ngenxa yezimpawu zokunciphisa i-shear yezixazululo ezinamanzi, i-viscosity yesisombululo iyancipha ngokunyuka kwezinga lokugunda, elivumela ukuhlakazeka okufanayo kwezinhlayiya ze-pigment, futhi kwandisa ukugeleza kwe-coating. .Umphumela mkhulu kakhulu;ngenkathi uphumule, i-viscosity yesixazululo inkulu kakhulu, okuvimbela ngokuphumelelayo ukubekwa kwezinhlayiya ze-pigment ekugqokeni.

02

I-HPMC Viscosity Test Indlela

Inkomba ebalulekile yokulinganisa umphumela wokujiya we-hydroxypropyl methylcellulose wukubona kwe-viscosity yesisombululo esinamanzi.Izindlela zokulinganisa ze-viscosity ebonakalayo ngokuvamile zihlanganisa indlela ye-capillary viscosity, indlela ye-rotational viscosity kanye nendlela ye-viscosity yebhola eliwayo.

lapho: i-viscosity ebonakalayo, i-mPa s;I-K yi-viscometer engaguquki;d ukuminyana kwesampula yesixazululo ku-20/20°C;t yisikhathi sokuthi ikhambi lidlule engxenyeni engenhla ye-viscometer kuya kumaki aphansi, s;Isikhathi lapho uwoyela ojwayelekile ugeleza nge-viscometer siyalinganiswa.

Kodwa-ke, indlela yokulinganisa nge-capillary viscometer inzima kakhulu.Ama-viscosities ama-cellulose ethers amaningi kunzima ukuwahlaziya kusetshenziswa i-capillary viscometer ngoba lezi zixazululo ziqukethe amanani omkhondo wento engancibilikiyo etholwa kuphela lapho i-capillary viscometer ivinjiwe.Ngakho-ke, abakhiqizi abaningi basebenzisa ama-viscometers ajikelezayo ukulawula ikhwalithi ye-hydroxypropyl methylcellulose.Ama-viscometer e-Brookfield avame ukusetshenziswa emazweni angaphandle, kanti ama-viscometer e-NDJ asetshenziswa e-China.

03

Izici ezithonya ze-HPMC viscosity

3.1 Ubudlelwano nezinga lokuhlanganisa

Lapho amanye amapharamitha ehlala engashintshiwe, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ilingana nezinga le-polymerization (DP) noma isisindo samangqamuzana noma ubude beketanga lamangqamuzana, futhi iyanda ngokunyuka kwezinga le-polymerization.Lo mphumela ubonakala kakhulu esimweni sezinga eliphansi le-polymerization kunesimo sezinga eliphezulu le-polymerization.

3.2 Ubudlelwano phakathi kwe-viscosity nokugxila

I-viscosity ye-hydroxypropyl methylcellulose iyanda ngokukhula kokugxila komkhiqizo kwisisombululo esinamanzi.Ngisho noshintsho oluncane lokuhlushwa luzobangela ushintsho olukhulu ku-viscosity.Nge-viscosity yegama le-hydroxypropyl methylcellulose Umphumela wokuguqulwa kokugxila kwesixazululo ku-viscosity yesixazululo ubonakala ngokusobala.

3.3 Ubudlelwano phakathi kwe-viscosity kanye ne-shear rate

I-Hydroxypropyl methylcellulose isixazululo esinamanzi sinendawo yokunciphisa i-shear.I-Hydroxypropyl methylcellulose ye-viscosity ehlukile yegama ilungiswa ibe yisisombululo samanzi esingu-2%, futhi i-viscosity yayo ngamazinga ahlukene okugunda kuyalinganiswa ngokulandelana.Imiphumela imi kanje Njengoba kuboniswe emfanekisweni.Ngezinga eliphansi le-shear, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ayizange ishintshe kakhulu.Ngokunyuka kwezinga le-shear, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ene-viscosity ephezulu yegama lehla ngokusobala, kuyilapho isixazululo esine-viscosity ephansi asizange sehle ngokusobala.

3.4 Ubudlelwano phakathi kwe-viscosity nezinga lokushisa

I-viscosity yesisombululo se-hydroxypropyl methylcellulose ithinteka kakhulu izinga lokushisa.Njengoba izinga lokushisa likhuphuka, i-viscosity yesisombululo iyancipha.Njengoba kuboniswe emfanekisweni, ilungiselelwe ibe yisisombululo se-aqueous nge-concentration ye-2%, futhi ukuguqulwa kwe-viscosity ngokunyuka kwezinga lokushisa kuyalinganiswa.

3.5 Ezinye izici ezinomthelela

I-viscosity yesisombululo esinamanzi se-hydroxypropyl methylcellulose nayo iyathinteka yizithasiselo ezisesixazululweni, inani le-pH lesisombululo, nokuwohloka kwe-microbial.Ngokuvamile, ukuze uthole ukusebenza okungcono kwe-viscosity noma ukunciphisa izindleko zokusetshenziswa, kuyadingeka ukwengeza ama-rheology modifiers, njengobumba, ubumba oluguquliwe, i-polymer powder, i-starch ether kanye ne-aliphatic copolymer, kusixazululo samanzi se-hydroxypropyl methylcellulose., kanye nama-electrolyte afana ne-chloride, i-bromide, i-phosphate, i-nitrate, njll.Lezi zengezo ngeke zithinte kuphela izakhiwo ze-viscosity zesisombululo se-aqueous, kodwa futhi zithinte ezinye izakhiwo zokusetshenziswa kwe-hydroxypropyl methylcellulose njengokugcinwa kwamanzi., ukumelana ne-sag, njll.

I-viscosity yesisombululo esinamanzi se-hydroxypropyl methylcellulose cishe ayithinteki nge-asidi ne-alkali, futhi ngokuvamile izinzile ku-3 kuya ku-11. Ingakwazi ukumelana nenani elithile lama-asidi abuthakathaka, njenge-formic acid, i-acetic acid, i-phosphoric acid. , i-boric acid, i-citric acid, njll. Nokho, i-asidi egxilile izonciphisa i-viscosity.Kodwa i-caustic soda, i-potassium hydroxide, amanzi e-lime, njll.Uma kuqhathaniswa namanye ama-cellulose ethers, isixazululo samanzi se-hydroxypropyl methylcellulose sinokuzinza okuhle kwe-antimicrobial, isizathu esiyinhloko ukuthi i-hydroxypropyl methylcellulose inamaqembu e-hydrophobic anezinga eliphezulu lokushintshwa kanye nesithiyo esiqinile samaqembu Kodwa-ke, njengoba ukusabela kokushintsha ngokuvamile akufani, iyunithi ye-anhydroglucose engashintshiwe. iguguleka kalula amagciwane, okuholela ekulimaleni kwamangqamuzana e-cellulose ether kanye ne-chain scission.Ukusebenza ukuthi i-viscosity ebonakalayo yesisombululo se-aqueous iyancipha.Uma kudingekile ukugcina isixazululo samanzi se-hydroxypropyl methylcellulose isikhathi eside, kunconywa ukwengeza inani elincane le-ejenti ye-antifungal ukuze i-viscosity ingashintshi kakhulu.Lapho ukhetha ama-anti-fungal agents, ama-preservatives noma ama-fungicides, kufanele unake ukuphepha, futhi ukhethe imikhiqizo engenabo ubuthi emzimbeni womuntu, enezindawo ezinzile futhi engenaphunga, njengama-fungicides e-DOW Chem's AMICAL, ama-preservatives e-CANGUARD64, ama-bacterium e-FUELSAVER. neminye imikhiqizo.ingadlala indima ehambisanayo.


Isikhathi sokuthumela: Oct-20-2022