IHydroxypropyl methylcellulose (HPMC) yikhompawundi yepolymer esetyenziswa ngokuqhelekileyo, isetyenziswa kakhulu kulwakhiwo, amayeza, ukutya kunye namanye amashishini. Njengepolymer enyibilikayo emanzini, i-HPMC inokugcinwa kwamanzi okugqwesileyo, ukwenza ifilimu, ukuqina kunye neempawu ze-emulsifying. Ukugcinwa kwayo kwamanzi yenye yezinto zayo ezibalulekileyo kwizicelo ezininzi, ngakumbi kwizinto ezifana nesamente, udaka kunye neengubo kwishishini lokwakha, ezinokulibazisa ukuvela kwamanzi kunye nokuphucula ukusebenza kokwakhiwa kunye nomgangatho wemveliso yokugqibela. Nangona kunjalo, ukugcinwa kwamanzi kwe-HPMC kuhambelana ngokusondeleyo nokutshintsha kweqondo lokushisa kwimeko yangaphandle, kwaye ukuqonda obu budlelwane kubalulekile ekusebenziseni kwayo kwiinkalo ezahlukeneyo.
1. Ubume kunye nokugcinwa kwamanzi kwe-HPMC
I-HPMC yenziwe ngokuguqulwa kweekhemikhali ze-cellulose yendalo, ngokukodwa ngokungeniswa kwe-hydroxypropyl (-C3H7OH) kunye namaqela e-methyl (-CH3) kwikhonkco le-cellulose, elinika ukunyibilika okulungileyo kunye neempawu zokulawula. Amaqela e-hydroxyl (-OH) kwiimolekyuli ze-HPMC angenza iibhondi ze-hydrogen kunye neemolekyuli zamanzi. Ngoko ke, i-HPMC inokufunxa amanzi kwaye idibanise namanzi, ibonisa ukugcinwa kwamanzi.
Ukugcinwa kwamanzi kubhekiselele kubuchule bento ukugcina amanzi. Kwi-HPMC, ibonakaliswe ngokukodwa kwikhono layo lokugcina umxholo wamanzi kwinkqubo ngokusebenzisa i-hydration, ngokukodwa kwiindawo eziphezulu zokushisa okanye kwiindawo zokufuma, ezinokuthintela ngokufanelekileyo ukulahleka kwamanzi ngokukhawuleza kunye nokugcina ukumanzi kwento. Ekubeni i-hydration kwiimolekyuli ze-HPMC inxulumene ngokusondeleyo nokusebenzelana kwesakhiwo sayo se-molecular, utshintsho lobushushu luya kuchaphazela ngokuthe ngqo umthamo wokufunxa kwamanzi kunye nokugcinwa kwamanzi kwe-HPMC.
2. Impembelelo yobushushu ekugcinweni kwamanzi eHPMC
Ubudlelwane phakathi kokugcinwa kwamanzi kwe-HPMC kunye nobushushu kunokuxoxwa ngazo kwimiba emibini: enye yimpembelelo yobushushu kwi-solubility ye-HPMC, kwaye enye isiphumo sobushushu kwisakhiwo sayo se-molecular kunye ne-hydration.
2.1 Impembelelo yobushushu kwi-solubility ye-HPMC
Ukunyibilika kwe-HPMC emanzini kuhambelana nobushushu. Ngokubanzi, ukunyibilika kwe-HPMC kwandisa ngokunyuka kwamaqondo obushushu. Xa iqondo lobushushu linyuka, iimolekyuli zamanzi zifumana amandla ashushu angakumbi, nto leyo ekhokelela ekunciphiseni intsebenziswano phakathi kweemolekyuli zamanzi, ngaloo ndlela ikhuthaza ukunyibilika. HPMC. Kwi-HPMC, ukunyuka kweqondo lokushisa kungenza kube lula ukwenza isisombululo se-colloidal, ngaloo ndlela siphucula ukugcinwa kwamanzi emanzini.
Nangona kunjalo, ubushushu obuphezulu kakhulu bunokunyusa i-viscosity yesisombululo se-HPMC, echaphazela iimpawu zayo ze-rheological kunye ne-dispersibility. Nangona le mpembelelo ilungile ekuphuculeni i-solubility, ukushisa okuphezulu kakhulu kunokutshintsha ukuzinza kwesakhiwo sayo se-molecular kwaye kukhokelela ekunciphiseni ukugcinwa kwamanzi.
2.2 Impembelelo yobushushu kwisakhiwo semolekyuli ye-HPMC
Kulwakhiwo lwemolekyuli ye-HPMC, iibhondi ze-hydrogen zenziwa ikakhulu ngeemolekyuli zamanzi ngokusebenzisa amaqela e-hydroxyl, kwaye le bhondi ye-hydrogen ibalulekile kugcino lwamanzi lwe-HPMC. Njengoko iqondo lokushisa linyuka, amandla ebhondi ye-hydrogen anokutshintsha, okubangela ukuba buthathaka kwamandla okubopha phakathi kwe-molecule ye-HPMC kunye ne-molecule yamanzi, ngaloo ndlela ichaphazela ukugcinwa kwayo kwamanzi. Ngokukodwa, ukunyuka kweqondo lokushisa kuya kubangela ukuba iibhondi ze-hydrogen kwi-molecule ye-HPMC zihlukane, ngaloo ndlela zinciphisa ukufunxa kwamanzi kunye nokugcinwa kwamanzi.
Ukongezelela, ukuvakalelwa kweqondo lokushisa kwe-HPMC kubonakaliswe kwindlela yokuziphatha kwesigaba sesisombululo sayo. I-HPMC enobunzima beemolekyuli ezahlukeneyo kunye namaqela abambeleyo ahlukeneyo aneemvakalelo ezahlukeneyo zobushushu. Ngokubanzi, ubunzima bemolekyuli ephantsi HPMC bunovakalelo ngakumbi kubushushu, ngelixa ubunzima obuphezulu bemolekyuli HPMC ibonisa ukusebenza okuzinzileyo. Ngoko ke, kwizicelo ezisebenzayo, kuyimfuneko ukukhetha uhlobo olufanelekileyo lwe-HPMC ngokoluhlu oluthile lweqondo lokushisa ukuqinisekisa ukugcinwa kwamanzi kwiqondo lokushisa lokusebenza.
2.3 Ifuthe lobushushu kubushushu bamanzi
Kwimekobume yobushushu obuphezulu, ukugcinwa kwamanzi kwe-HPMC kuya kuchatshazelwa kukunyuka kwamanzi okuba ngumphunga okubangelwa kukwanda kobushushu. Xa ubushushu bangaphandle buphezulu kakhulu, amanzi akwinkqubo ye-HPMC kunokwenzeka ukuba abe ngumphunga. Nangona i-HPMC inokugcina amanzi ukuya kumlinganiselo othile ngolwakhiwo lwemolekyuli, ubushushu obugqithisileyo bunokubangela ukuba inkqubo ilahlekelwe ngamanzi ngokukhawuleza kunomthamo wokugcina amanzi we-HPMC. Kule meko, ukugcinwa kwamanzi kwe-HPMC kuthintelwe, ngokukodwa kwiqondo lokushisa eliphezulu kunye nendawo eyomileyo.
Ukunciphisa le ngxaki, ezinye izifundo zibonise ukuba ukongeza i-humectants efanelekileyo okanye ukulungelelanisa amanye amacandelo kwifomula kunokuphucula umphumo wokugcinwa kwamanzi we-HPMC kwindawo yokushisa ephezulu. Ngokomzekelo, ngokulungelelanisa i-viscosity modifier kwi-formula okanye ukukhetha i-solvent ephantsi, ukugcinwa kwamanzi kwe-HPMC kunokuphuculwa kwinqanaba elithile, ukunciphisa umphumo wokunyuka kweqondo lokushisa kwi-evaporation yamanzi.
3. Imiba enempembelelo
Isiphumo sobushushu kugcino lwamanzi HPMC ayixhomekanga kuphela kwiqondo lobushushu ambient ngokwayo, kodwa ubunzima molekyuli, degree of substitution, ingxinano isisombululo kunye nezinye izinto HPMC. Umzekelo:
Ubunzima bemolekyuli:HPMC ngobunzima obuphezulu bemolekyuli ngokuqhelekileyo inokugcinwa kwamanzi okunamandla, kuba isakhiwo sothungelwano esakhiwe ngamatyathanga obunzima bemolekyuli ephezulu kwisisombululo sinokufunxa kwaye sigcine amanzi ngokufanelekileyo.
I-Degree yokutshintshwa: Iqondo le-methylation kunye ne-hydroxypropylation ye-HPMC iya kuchaphazela ukusebenzisana kwayo kunye neemolekyuli zamanzi, ngaloo ndlela ichaphazela ukugcinwa kwamanzi. Ngokubanzi, iqondo eliphezulu lokutshintshwa linokuphucula i-hydrophilicity ye-HPMC, ngaloo ndlela iphucula ukugcinwa kwayo kwamanzi.
Ugxininiso lwesisombululo: Uxinzelelo lwe-HPMC lukwachaphazela ukugcinwa kwayo kwamanzi. Ugxininiso oluphezulu lwezisombululo ze-HPMC ludla ngokuba neziphumo ezingcono zogcino lwamanzi, kuba ugxininiso oluphezulu lwe-HPMC lunokugcina amanzi ngonxibelelwano olomeleleyo lwe-intermolecular.
Kukho ubudlelwane obunzima phakathi kokugcinwa kwamanziHPMCkunye nobushushu. Ukushisa okunyukayo ngokuqhelekileyo kukhuthaza ukunyibilika kwe-HPMC kwaye kunokukhokelela ekuphuculeni ukugcinwa kwamanzi, kodwa ukushisa okuphezulu kakhulu kuya kutshabalalisa isakhiwo se-molecular of HPMC, ukunciphisa amandla ayo okubopha emanzini, kwaye ngaloo ndlela kuchaphazela umphumo wokugcinwa kwamanzi. Ukuze kuphunyezwe ukusebenza kakuhle kokugcinwa kwamanzi phantsi kweemeko ezahlukeneyo zobushushu, kuyimfuneko ukukhetha uhlobo olufanelekileyo lwe-HPMC ngokweemfuno ezithile zesicelo kunye nokulungelelanisa ngokufanelekileyo iimeko zokusetyenziswa kwayo. Ukongeza, amanye amacandelo kwifomula kunye nezicwangciso zokulawula ubushushu zinokuphucula ukugcinwa kwamanzi kwe-HPMC kwindawo yobushushu obuphezulu ukuya kumlinganiselo othile.
Ixesha lokuposa: Nov-11-2024