I-Hydroxypropylmethylcellulose (HPMC), njenge-polymer eyi-hydrophilic evame ukusetshenziswa embonini yezemithi, isetshenziswa kakhulu embotsheni yamathebulethi, ekwakhiweni kokukhishwa okulawulwayo kanye nezinye izinhlelo zokulethwa kwezidakamizwa.Enye yezinto ezibalulekile ze-HPMC yikhono layo lokugcina amanzi, okuthinta ukusebenza kwayo njengesithako semithi.Kulesi sihloko, sizohlola izici ezibalulekile ezithinta ukugcinwa kwamanzi kwe-HPMC, okuhlanganisa isisindo samangqamuzana, uhlobo lokufaka esikhundleni, ukugxila, kanye ne-pH.
isisindo samangqamuzana
Isisindo samangqamuzana e-HPMC sidlala indima ebalulekile ekunqumeni umthamo wayo wokugcina amanzi.Ngokuvamile, isisindo samangqamuzana aphezulu i-HPMC ine-hydrophilic kakhulu kune-HPMC enesisindo esiphansi futhi ingamunca amanzi amaningi.Lokhu kungenxa yokuthi ama-HPMC esisindo samangqamuzana aphezulu anamaketanga amade angagoqa futhi akhe inethiwekhi ebanzi, okwandisa inani lamanzi angamuncwa.Kodwa-ke, kufanele kuqashelwe ukuthi i-HPMC ephezulu kakhulu yesisindo samangqamuzana izodala izinkinga ezifana ne-viscosity kanye nobunzima bokucubungula.
okunye
Esinye isici esithinta umthamo wokugcina amanzi we-HPMC uhlobo lokushintsha.I-HPMC ngokuvamile iza ngezindlela ezimbili: i-hydroxypropyl-substituted kanye ne-methoxy-substituted.Uhlobo olufakwe esikhundleni se-hydroxypropyl lunamandla okumunca amanzi aphezulu kunohlobo olufakwe endaweni ye-methoxy.Lokhu kungenxa yokuthi iqembu le-hydroxypropyl elikhona ku-molecule ye-HPMC liyi-hydrophilic futhi likhulisa ukuhlobana kwe-HPMC emanzini.Ngokuphambene, uhlobo olufakwe esikhundleni se-methoxy lune-hydrophilic encane futhi ngenxa yalokho lunomthamo ophansi wokugcina amanzi.Ngakho-ke, ezinye izinhlobo ze-HPMC kufanele zikhethwe ngokucophelela ngokusekelwe ezintweni ezifiselekayo zomkhiqizo wokugcina.
gxila ku
Ukugxila kwe-HPMC kuphinde kuthinte umthamo wayo wokugcina amanzi.Ezimweni eziphansi, i-HPMC ayakhi isakhiwo esifana nejeli, ngakho-ke umthamo wayo wokugcina amanzi uphansi.Njengoba ukugxila kwe-HPMC kwanda, ama-molecule e-polymer aqala ukugoqa, enza isakhiwo esifana nejeli.Le nethiwekhi yejeli imunca futhi igcine amanzi, futhi amandla okugcina amanzi e-HPMC akhuphuka ngokugxilisa ingqondo.Kodwa-ke, kufanele kuqashelwe ukuthi ukugcwala okuphezulu kakhulu kwe-HPMC kuzoholela ezinkingeni zokwakheka ezifana ne-viscosity kanye nobunzima bokucubungula.Ngakho-ke, ukugxila kwe-HPMC esetshenzisiwe kufanele kuthuthukiswe ukuze kuzuzwe umthamo ofunekayo wokugcina amanzi ngenkathi kugwenywa izinkinga ezishiwo ngenhla.
PH inani
Inani le-pH lendawo lapho kusetshenziswa i-HPMC lizophinde lithinte umthamo wayo wokugcina amanzi.Isakhiwo se-HPMC siqukethe amaqembu e-anionic (-COO-) namaqembu e-hydrophilic ethylcellulose (-OH).I-ionization yamaqembu -COO- incike ku-pH, futhi i-ionization degree yawo ikhuphuka nge-pH.Ngakho-ke, i-HPMC inomthamo ophezulu wokugcina amanzi ku-pH ephezulu.Nge-pH ephansi, i-COO-group i-protonated futhi i-hydrophilicity yayo iyancipha, okuholela ekunciphiseni umthamo wokugcina amanzi.Ngakho-ke, i-pH yemvelo kufanele ithuthukiswe ukuze kuzuzwe umthamo ofunekayo wokugcina amanzi we-HPMC.
Ekuphetheni
Sengiphetha, amandla okugcina amanzi e-HPMC iyisici esibalulekile esithinta ukusebenza kwayo njengengxenye yezemithi.Izinto ezibalulekile ezithinta amandla okugcina amanzi e-HPMC zihlanganisa isisindo samangqamuzana, uhlobo lokushintsha, ukugxilisa ingqondo kanye nenani le-pH.Ngokulungisa ngokucophelela lezi zici, amandla okugcina amanzi e-HPMC angathuthukiswa ukuze kuzuzwe izici ezifiselekayo zomkhiqizo wokugcina.Abacwaningi bemithi nabakhiqizi kufanele banake kakhulu lezi zici ukuze baqinisekise ikhwalithi ephezulu kakhulu nokusebenza kokwakhiwa kwezidakamizwa okusekelwe ku-HPMC.
Isikhathi sokuthumela: Aug-05-2023