I-Hydroxypropylmethylcellulose (HPMC), njenge-polymer evame ukusetshenziswa kakhulu embonini yezemithi, isetshenziswa kabanzi ekumbozweni kwamathebulethi, ekubunjweni kokukhishwa okulawulwayo nakwezinye izinhlelo zokulethwa kwemithi. Enye yezimpawu ezibalulekile ze-HPMC yikhono layo lokugcina amanzi, okuthinta ukusebenza kwayo njengesithako semithi. Kulesi sihloko, sizohlola izici ezibalulekile ezithinta ukugcinwa kwamanzi kwe-HPMC, okuhlanganisa isisindo sama-molecule, uhlobo lokufaka esikhundleni, ukuhlushwa, kanye ne-pH.
isisindo sama-molecule
Isisindo sama-molecule se-HPMC sidlala indima ebalulekile ekunqumeni amandla ayo okugcina amanzi. Ngokuvamile, i-HPMC enesisindo sama-molecule esiphezulu ithanda kakhulu amanzi kune-HPMC enesisindo sama-molecule esincane futhi ingamunca amanzi amaningi. Lokhu kungenxa yokuthi ama-HPMC anesisindo sama-molecule esiphezulu anezintambo ezinde ezingabambisa futhi zakhe inethiwekhi ebanzi kakhulu, okwandisa inani lamanzi angamuncwa. Kodwa-ke, kufanele kuqashelwe ukuthi i-HPMC enesisindo sama-molecule esiphezulu kakhulu izobangela izinkinga ezifana nokuxinana kanye nobunzima bokucubungula.
okunye
Esinye isici esithinta amandla okugcina amanzi e-HPMC uhlobo lokushintshana. I-HPMC ngokuvamile iza ngezindlela ezimbili: i-hydroxypropyl-substituted kanye ne-methoxy-substituted. Uhlobo lwe-hydroxypropyl-substituted lunamandla aphezulu okumunca amanzi kunohlobo lwe-methoxy-substituted. Lokhu kungenxa yokuthi iqembu le-hydroxypropyl elikhona ku-molecule ye-HPMC lithanda amanzi futhi landisa ukuhambisana kwe-HPMC namanzi. Ngokuphambene nalokho, uhlobo lwe-methoxy-substituted aluthandi amanzi kakhulu ngakho-ke lunamandla okugcina amanzi aphansi. Ngakho-ke, izinhlobo ezihlukile ze-HPMC kufanele zikhethwe ngokucophelela ngokusekelwe ezicini ezifiselekayo zomkhiqizo wokugcina.
gxila ku
Ukuhlushwa kwe-HPMC nakho kuthinta amandla ayo okugcina amanzi. Uma kuhlushwa okuphansi, i-HPMC ayakhi isakhiwo esifana nejeli, ngakho-ke amandla ayo okugcina amanzi aphansi. Njengoba ukuhlushwa kwe-HPMC kwanda, ama-molecule e-polymer aqala ukugxamalaza, akha isakhiwo esifana nejeli. Le nethiwekhi yejeli imunca futhi igcine amanzi, futhi amandla okugcina amanzi e-HPMC ayanda ngokuhlushwa. Kodwa-ke, kufanele kuqashelwe ukuthi ukuhlushwa okuphezulu kakhulu kwe-HPMC kuzoholela ezinkingeni zokwakheka ezifana nokuxinana nobunzima bokucubungula. Ngakho-ke, ukuhlushwa kwe-HPMC esetshenziswayo kufanele kulungiselelwe ukufeza amandla okugcina amanzi afunekayo ngenkathi kugwenywa izinkinga ezishiwo ngenhla.
Inani le-PH
Inani le-pH lendawo lapho i-HPMC isetshenziswa khona lizothinta nomthamo wayo wokugcina amanzi. Isakhiwo se-HPMC siqukethe amaqembu e-anionic (-COO-) kanye namaqembu e-hydrophilic ethylcellulose (-OH). I-ionization yamaqembu e-COO- incike ku-pH, futhi izinga lawo le-ionization liyakhuphuka nge-pH. Ngakho-ke, i-HPMC inomthamo wokugcina amanzi ophezulu ku-pH ephezulu. Ku-pH ephansi, iqembu le-COO- liyavela futhi i-hydrophilicity yalo iyancipha, okuholela ekutheni umthamo wokugcina amanzi ube phansi. Ngakho-ke, i-pH yemvelo kufanele ilungiselelwe ukuze kufezwe umthamo wokugcina amanzi ofiselekayo we-HPMC.
Ekuphetheni
Ekuphetheni, amandla okugcina amanzi e-HPMC ayisici esibalulekile esithinta ukusebenza kwayo njengesithako semithi. Izici ezibalulekile ezithinta amandla okugcina amanzi e-HPMC zifaka phakathi isisindo sama-molecule, uhlobo lokufaka esikhundleni, ukuhlushwa kanye nenani le-pH. Ngokulungisa ngokucophelela lezi zici, amandla okugcina amanzi e-HPMC angathuthukiswa ukuze kufezwe izakhiwo ezifiselekayo zomkhiqizo wokugcina. Abacwaningi bemithi nabakhiqizi kufanele banake kakhulu lezi zici ukuqinisekisa ikhwalithi ephezulu kanye nokusebenza kwemithi esekelwe ku-HPMC.
Isikhathi sokuthunyelwe: Agasti-05-2023