IHydroxypropyl methylcellulose (HPMC) iyi-polymer eguquguqukayo esetshenziswa kabanzi njengokuqina ezimbonini ezahlukahlukene ezifana nemithi, izimonyo, ukudla, nezinto zokwakha. Ukuqonda izakhiwo ze-rheological zezinhlelo ze-HPMC thickener kubalulekile ekuthuthukiseni ukusebenza kwazo ezinhlelweni ezahlukene.
1. I-Viscosity:
Amasistimu okuqina e-HPMC abonisa ukuziphatha kokushear, okusho ukuthi i-viscosity yawo iyancipha ngokwenyuka kwezinga lokugunda. Lesi sakhiwo sinenzuzo ezinhlelweni zokusebenza lapho isicelo esilula noma ukucutshungulwa kuyadingeka, njengakumapende nama-coatings.
I-viscosity yezixazululo ze-HPMC ithonywa izici ezifana nokugxila kwe-polymer, isisindo samangqamuzana, i-substitution degree, izinga lokushisa, nezinga lokugunda.
Ngamazinga aphansi okugunda, izixazululo ze-HPMC ziziphatha njengoketshezi lwe-viscous olune-viscosity ephezulu, kuyilapho kumazinga aphezulu okugunda, ziziphatha njengoketshezi oluncane lwe-viscous, lwenza lula ukugeleza.
2. Thixotropy:
Thixotropy ibhekisela endaweni yoketshezi oluthile ukuze kubuye i-viscosity yayo lapho imile ngemva kokuba ngaphansi kwengcindezi yokugunda. Izinhlelo ze-HPMC thickener zivame ukubonisa ukuziphatha kwe-thixotropic.
Lapho ingaphansi kwengcindezi yokugunda, amaketanga e-polymer amade aqondana lapho kugeleza khona, ehlisa i-viscosity. Lapho sekuphelile ukucindezelwa kwe-shear, amaketanga e-polymer kancane kancane abuyela ekuqondeni kwawo okungahleliwe, okuholela ekwandeni kwe-viscosity.
Thixotropy iyathandeka ezinhlelweni ezifana nezingubo zokunamathisela kanye ne-adhesives, lapho impahla idinga ukugcina ukuzinza ngesikhathi sokufaka isicelo kodwa igeleza kalula ngaphansi kwe-shear.
3. Yield Stress:
Amasistimu okuqina we-HPMC avame ukuba nengcindezi yesivuno, okuyingcindezi encane edingekayo ukuze kuqalwe ukugeleza. Ngaphansi kwalokhu kucindezeleka, okubalulekile kuziphatha njengokuqinile, okubonisa ukuziphatha okunwebekayo.
Ukucindezelwa kwesivuno kwezixazululo ze-HPMC kuncike ezintweni ezifana nokugxila kwe-polymer, isisindo samangqamuzana, kanye nezinga lokushisa.
Ukucindezeleka kwesivuno kubalulekile ekusetshenzisweni lapho okubalulekile kudinga ukuhlala endaweni ngaphandle kokugeleza ngaphansi kwesisindo saso, njengasezimbozweni eziqondile noma ekumisweni kwezinhlayiya eziqinile kumapende.
4. Ukuzwela kwezinga lokushisa:
I-viscosity yezixazululo ze-HPMC ithonywa izinga lokushisa, i-viscosity ngokuvamile iyancipha njengoba izinga lokushisa likhuphuka. Lokhu kuziphatha kujwayelekile kwezixazululo ze-polymer.
Ukuzwela kwezinga lokushisa kungathinta ukuvumelana nokusebenza kwamasistimu okuqina kwe-HPMC ezinhlelweni ezihlukene, okudinga ukulungiswa ekwakhiweni noma ukucubungula amapharamitha ukuze kugcinwe izakhiwo ezifiselekayo kuwo wonke amabanga ahlukene okushisa.
5. Ukuncika Kwezinga Le-Shear:
I-viscosity yezixazululo ze-HPMC incike kakhulu kuzinga lokugunda, namazinga aphezulu okugunda okuholela ekubonakaleni okuphansi ngenxa yokuqondanisa nokwelula kwamaketanga e-polymer.
Lokhu kuncika kwezinga le-shear kuvame ukuchazwa umthetho-mthetho noma amamodeli e-Herschel-Bulkley, ahlobanisa ingcindezi yokugunda nezinga lokugunda kanye nengcindezi yokukhiqiza.
Ukuqonda ukuncika kwesilinganiso sokugunda kubalulekile ekubikezeleni nasekulawuleni ukuziphatha kokugeleza kwezinhlelo zokujiya ze-HPMC ezinhlelweni ezisebenzayo.
6. I-Concentration Effects:
Ukwandisa ukugxila kwe-HPMC esixazululweni ngokuvamile kuholela ekwandeni kwe-viscosity kanye nengcindezi yokukhiqiza. Lo mphumela wokugxilisa ingqondo ubalulekile ukuze kuzuzwe ukuvumelana okufiselekayo nokusebenza ezinhlelweni ezihlukahlukene.
Kodwa-ke, ekugxilweni okuphezulu kakhulu, izixazululo ze-HPMC zingase zibonise ukuziphatha okufana nejeli, ukwakha isakhiwo senethiwekhi esikhulisa kakhulu i-viscosity kanye nokucindezeleka kwesivuno.
7. Ukuxuba kanye Nokusabalalisa:
Ukuxutshwa okufanele nokuhlakazwa kwe-HPMC kusixazululo kubalulekile ukuze kuzuzwe i-viscosity efanayo kanye nezakhiwo ze-rheological kulo lonke uhlelo.
Ukuhlakazwa okungaphelele noma ukuhlanganisana kwezinhlayiya ze-HPMC kungaholela ku-viscosity engafaniswanga kanye nokusebenza okuxekethile ezinhlelweni ezifana nezingubo zokunamathela nezinamatheliso.
Kungase kusetshenziswe izindlela ezihlukahlukene zokuhlanganisa nezithasiselo ukuze kuqinisekiswe ukuhlakazeka okuphelele nokusebenza kwamasistimu okuqina we-HPMC.
Izici ze-rheological zezinhlelo ze-HPMC thickener, okuhlanganisa i-viscosity, i-thixotropy, ingcindezi yesivuno, ukuzwela kwezinga lokushisa, ukuncika kwezinga le-shear, imiphumela yokugxilisa ingqondo, nokuziphatha kokuxuba/nokuhlakazeka, kudlala indima ebalulekile ekunqumeni ukusebenza kwazo ezinhlelweni ezihlukahlukene. Ukuqonda nokulawula lezi zakhiwo kubalulekile ekwakhekeni kwemikhiqizo esekwe ku-HPMC ngokungaguquguquki, ukuzinza, nokusebenza okufunayo.
Isikhathi sokuthumela: May-08-2024