I-Hydroxypropyl methylcellulose (HPMC)iyi-non-ionic, i-cellulose exutshwe ne-ether encibilikayo emanzini. 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 emigqonyeni, ngenxa yezimpawu zokunciphisa i-shear yezixazululo ezinamanzi, i-viscosity yesisombululo iyancipha ngokunyuka kwezinga le-shear, elihambisana nokuhlakazeka 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. I-viscosities yabaningii-cellulose etherskunzima ukuhlaziya kusetshenziswa i-capillary viscometer ngoba lezi zixazululo ziqukethe amanani omkhondo wento engancibiliki atholwa 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 ebangeni le-3 kuya ku-11. Ingakwazi ukumelana nenani elithile lama-acids abuthakathaka, njenge-formic acid, i-acetic acid, i-phosphoric acid, i-boric acid, i-citric acid, njll. Nokho, i-viscorated acid izonciphisa. Kodwa i-caustic soda, i-potassium hydroxide, amanzi e-lime, njll. Uma kuqhathaniswa namanye ama-cellulose ethers,i-hydroxypropyl methylcelluloseIsixazululo esinamanzi sinokuzinza okuhle kwe-antimicrobial, isizathu esiyinhloko ukuthi i-hydroxypropyl methylcellulose inamaqembu e-hydrophobic anezinga eliphezulu lokushintshwa kanye nesithiyo se-steric samaqembu Kodwa-ke, njengoba ukusabela kokubuyisela ngokuvamile akufani, iyunithi ye-anhydroglucose engashintshiwe iguguleka kalula yi-microorganisms, okuholela ekuwohlokeni kwe-molecule ye-cellsulose. 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 ezingenaphunga, njengama-fungicides e-DOW Chem's AMICAL, ama-preservatives e-CANGUARD64, ama-bacterium e-FUELSAVER neminye imikhiqizo. ingadlala indima ehambisanayo.
Isikhathi sokuthumela: Apr-28-2024