I-Hydroxypropylmethylcellellellellellellulose (HPMC) iyindawo eye yaba yinto ebabazekayo emikhakheni eminingi ngenxa yezakhiwo zayo ezisebenzayo. Isetshenziswa kakhulu njengesengezo sokudla, isikhulisi sezimonyo, kanye nesithako sezokwelapha emithini eminingi. Impahla eyingqayizivele ye-HPMC yokuziphatha kwayo ye-Thixotropic, okuvumela ukuthi iguqule ukwakheka kanye nokugeleza kwezimo ngaphansi kwezimo ezithile. Ngaphezu kwalokho, kokubili okubonakalayo kanye nokuvunywa okuphansi kwe-HPMC ephansi kunale ndawo, kukhombisa i-thixotropy ngisho nangaphansi kwe-gel lokushisa.
I-Thixotropy yenzeka ku-HPMC lapho isisombululo siba shuarng lapho ingcindezi isetshenziswa noma ivuselelwa, okuholela ekwehliseni ekuboneni. Lokhu kuziphatha kungabuye kubuyiselwe emuva; Lapho ukucindezelwa kususwa futhi ikhambi lishiywe ukuze liphumule, i-viscosity ibuyela kancane esimweni sayo esiphakeme. Le mpahla eyingqayizivele yenza i-HPMC ibe yingxenye ebalulekile ezimbonini eziningi njengoba ivumela uhlelo lokusebenza olubushelelezi nokucutshungulwa okulula.
Njenge-hydrocollolroid ye-nonion, i-HPMC ivuvukala emanzini ukuze kwakhiwe ijeli. Izinga lokuvuvukala kanye nokugcwala kuncike kusisindo samangqamuzana kanye nokuhlushwa kwe-polymer, i-pH kanye nokushisa kwesisombululo. I-Vissevosity ephezulu i-HPMC imvamisa inesisindo esiphakeme samangqamuzana futhi ikhiqize i-gelcosity yejeli ephezulu, ngenkathi i-viscosity ephansi i-HPMC inesisindo esiphansi samangqamuzana futhi ikhiqiza ijeli eliphansi le-viscous. Kodwa-ke, naphezu kwalolu mehluko ekusebenzeni, zombili izinhlobo zama-HPMCS akhombisa i-thixotropy ngenxa yezinguquko ezenzeka ezingeni lamangqamuzana.
Ukuziphatha kwe-Thixotropic kwe-HPMC kungumphumela wokuqondanisa kwamaketanga we-polymer ngenxa yokuxineka kwe-shear. Lapho ukucindezelwa kwe-shear kufakwa ku-HPMC, amaketanga e-polymer avumelanisa ngokuqondiswa kwengcindezi esetshenzisiwe, okuholela ekubhujisweni kwesakhiwo senethiwekhi enezici ezintathu ezasikhona lapho kungekho khona ukucindezela. Ukuphazamiseka kwemiphumela yenethiwekhi ekwehliseni kokuboniswa kwesixazululo. Lapho ukucindezelwa kususwa, amaketanga e-polymer ahlele kabusha ngokulandelana kwawo kwasekuqaleni, ukwakha kabusha inethiwekhi nokubuyisela ukubonakala.
I-HPMC ibuye ikhombisa i-Thixotropy ngaphansi kwamazinga okushisa akwa-gelling. Ukushisa kwe-gel kungamazinga okushisa lapho amaketanga e-polymer awela khona ukuwela inethiwekhi enezici ezintathu, akha ijeli. Kuya ngesisindo, isisindo samangqamuzana nakusixazululo sekhambi le-polymer. Ijeli eliphumayo linokubonakala okuphezulu futhi aliguquki ngokushesha ngaphansi kwengcindezi. Kodwa-ke, ngaphansi kokushisa kwe-gelation, ikhambi le-HPMC lihlala liketshezi, kepha namanje likhombise ukusebenza kwe-thixotropic ngenxa yokuba khona kwesakhiwo senethiwekhi esakhelwe ngokwengxenye. Inethiwekhi eyakheka yilezi zingxenye ihlukana ngaphansi kwengcindezi, okuholela ekunciphiseni ekuboneni. Lokhu kuziphatha kuyazuzisa kuzinhlelo zokusebenza eziningi lapho izixazululo zidinga ukugeleza kalula lapho zivuswa.
I-HPMC ingamakhemikhali ahlukahlukene anezakhiwo ezimbalwa eziyingqayizivele, enye yazo yokuziphatha kwayo ye-thixotropic. Kokubili ukubonakala okuphezulu kanye ne-HPMCS ephansi ephansi inale mpahla, kukhombisa i-thixotropy ngisho nangaphansi kwe-gel lokushisa. Lesi sici senza i-HPMC ibe yingxenye ebalulekile emikhakheni eminingi edinga izixazululo ezisingatha ukuhamba okulula ukuze kuqinisekiswe uhlelo lokusebenza oluhle. Naphezu kokwehlukahlukana kwezindawo eziphakathi kokubonakala okuphezulu kanye ne-HPMCS ephansi-i-vissusious HPMCS, ukusebenza kwawo kwe-Thixotropic kwenzeka ngenxa yokuhlangana kanye nokuphazamiseka kwesakhiwo senethiwekhi esakhelwe ngokwengxenye. Ngenxa yezakhiwo zayo ezihlukile, abacwaningi bahlola njalo ukusetshenziswa okuhlukahlukene kwe-HPMC, banethemba lokudala imikhiqizo emisha futhi banikeze izisombululo ezingcono zabathengi emhlabeni jikelele.
Isikhathi sePosi: Aug-23-2023