IHydroxypropyl Methylcellulose (HPMC) yipolymer ebalulekileyo enyibilikayo emanzini esetyenziswa kakhulu kumayeza, ukutya, iingubo, izinto zokwakha kunye nezinye iindawo. I-viscosity yesisombululo ye-HPMC yinto ephambili echaphazela ukusebenza kwayo kunye nokusetyenziswa kwayo, kwaye ubushushu bunempembelelo enkulu kwi-viscosity ye-HPMC isisombululo samanzi.
1. Iimpawu ze-Viscosity zesisombululo se-HPMC
I-HPMC yimathiriyeli yepolymer eneempawu zokunyibilika ezibuyiselwa umva. Xa i-HPMC inyibilika emanzini, isisombululo esinamanzi enziweyo sibonisa iimpawu ze-non-Newtonian fluid, oko kukuthi, i-viscosity yesisombululo iyatshintsha kunye notshintsho kwizinga lokucheba. Kwiqondo lokushisa eliqhelekileyo, izisombululo ze-HPMC zihlala ziziphatha njenge-pseudoplastic fluids, oko kukuthi, zine-viscosity ephezulu kumazinga aphantsi okucheba, kwaye i-viscosity iyancipha njengoko izinga lokucheba linyuka.
2. Umphumo weqondo lokushisa kwi-viscosity yesisombululo se-HPMC
Utshintsho lobushushu luneendlela ezimbini eziphambili zempembelelo kwi-viscosity ye-HPMC izisombululo zamanzi: ukunyuka kwentshukumo ye-thermal yamatyathanga eemolekyuli kunye notshintsho kwintsebenziswano yesisombululo.
(1) Ukuhamba kwe-thermal yamaketanga e-molecular kwandisa
Xa iqondo lobushushu linyuka, intshukumo thermal HPMC chain imolekyuli ukwanda, nto leyo ebangela bonds hydrogen kunye van der Waals imikhosi phakathi iimolekyuli ukuba buthathaka kunye fluidity yesisombululo ukwandisa. I-viscosity yesisombululo iyancipha ngenxa yokunciphisa i-entanglement kunye nokudibanisa ngokomzimba phakathi kwamakhonkco e-molecular. Ke ngoko, izisombululo zamanzi ze-HPMC zibonisa i-viscosity esezantsi kumaqondo obushushu aphezulu.
(2) Utshintsho kwintsebenziswano yesisombululo
Utshintsho lobushushu lunokuchaphazela ukunyibilika kweemolekyuli zeHPMC emanzini. I-HPMC i-polymer eneempawu ze-thermogelling, kwaye ukunyibilika kwayo emanzini kuyatshintsha kakhulu ngobushushu. Kwiqondo lokushisa elisezantsi, amaqela e-hydrophilic kwitsheyina le-molecular ye-HPMC enza iibhondi ze-hydrogen ezizinzileyo kunye neemolekyuli zamanzi, ngaloo ndlela zigcina ukunyibilika okulungileyo kunye ne-viscosity ephezulu. Nangona kunjalo, xa iqondo lokushisa liphakama kwinqanaba elithile, ukusebenzisana kwe-hydrophobic phakathi kwe-HPMC yamaketane eemolekyuli kuphuculwe, okukhokelela ekubunjweni kwesakhiwo sothungelwano esine-ntathu-dimensional okanye i-gelation kwisisombululo, okubangela ukuba i-viscosity yesisombululo inyuke ngokukhawuleza phantsi kweemeko ezithile. Le nto ibizwa ngokuba yi "thermal gel" phenomenon.
3. Ukuqwalaselwa kovavanyo lobushushu kwi-viscosity yesisombululo se-HPMC
Uphononongo lovavanyo lubonise ukuba ngaphakathi koluhlu oluqhelekileyo lobushushu (umzekelo, i-20 ° C ukuya kuma-40 ° C), i-viscosity ye-HPMC izisombululo zamanzi ziyancipha ngokuthe ngcembe ngokunyuka kwamaqondo obushushu. Oku kungenxa yokuba amaqondo okushisa aphezulu anyusa amandla e-kinetic amatyathanga eemolekyuli kunye nokunciphisa ukusebenzisana kwe-intermolecular, ngaloo ndlela kuncitshiswe ukungqubuzana kwangaphakathi kwesisombululo. Nangona kunjalo, xa ubushushu buqhubeka nokunyuka ukuya kwindawo ye-thermal gel ye-HPMC (ngokuqhelekileyo phakathi kwe-60 ° C kunye ne-90 ° C, kuxhomekeke kwiqondo lokutshintshwa kunye nobunzima be-molecular ye-HPMC), i-viscosity yesisombululo iyanda ngokukhawuleza. Ukwenzeka kwesi siganeko kunxulumene nokudibanisa kunye kunye nokudibanisa kwamakhonkco e-molecular HPMC.
4. Ubudlelwane phakathi kobushushu kunye neeparamitha zesakhiwo seHPMC
I-viscosity yesisombululo se-HPMC ayichaphazeli nje kuphela ubushushu, kodwa inxulumene ngokusondeleyo nesakhiwo sayo se-molecular. Umzekelo, iqondo lokutshintshwa (okt, umxholo we-hydroxypropyl kunye ne-methyl substituents) kunye nobunzima bemolekyuli ye-HPMC inefuthe elibalulekileyo kukuziphatha kwayo kwejeli ye-thermal. I-HPMC eneqondo eliphezulu lokutshintshwa igcina i-viscosity ephantsi kuluhlu olubanzi lobushushu ngenxa yamaqela ayo angaphezulu kwe-hydrophilic, ngelixa i-HPMC eneqondo eliphantsi lokutshintshwa kunokwenzeka ukuba yenze iijeli ze-thermal. Ukongeza, izisombululo ze-HPMC ezinobunzima obuphezulu bemolekyuli zinokunyuka kwi-viscosity kumaqondo obushushu aphezulu.
5. Iingqwalasela zeSicelo soShishino kunye nesiSebenzayo
Kwizicelo ezisebenzayo, iintlobo ezifanelekileyo zeHPMC kufuneka zikhethwe ngokweemeko ezithile zobushushu. Ngokomzekelo, kwiindawo ezinobushushu obuphezulu, i-HPMC enokumelana nobushushu obuphezulu kufuneka ikhethwe ukuphepha i-thermal gelation. Ngaphantsi kweemeko zobushushu obuphantsi, ukunyibilika kunye nokuzinza kwe-viscosity ye-HPMC kufuneka kuthathelwe ingqalelo.
Isiphumo sobushushu kwi-viscosity ye-HPMC isisombululo samanzi sinokubaluleka okusebenzayo okubalulekileyo. Kwintsimi yamachiza, i-HPMC isetyenziswa rhoqo njengento eqhubekayo yokukhutshwa kumalungiselelo amayeza, kunye neempawu zayo ze-viscosity zichaphazela ngokuthe ngqo izinga lokukhutshwa kweziyobisi. Kwishishini lokutya, i-HPMC isetyenziselwa ukuphucula ukuthungwa kunye nokuzinza kweemveliso, kunye nokuxhomekeka kobushushu be-viscosity yayo yesisombululo kufuneka ihlengahlengiswe ngokuhambelana nobushushu bokusebenza. Kwizinto zokwakha, i-HPMC isetyenziswa njenge-ejenti yokuqina kunye nokugcina amanzi, kwaye iimpawu zayo ze-viscosity zichaphazela ukusebenza kokwakhiwa kunye namandla ezinto eziphathekayo.
Umphumo weqondo lokushisa kwi-viscosity ye-HPMC isisombululo se-aqueous yinkqubo enzima ebandakanya ukunyakaza kwe-thermal ye-molecular chain, ukusebenzisana kwesisombululo, kunye nezakhiwo zesakhiwo sepolymer. Ngokubanzi, i-viscosity ye-HPMC izisombululo zamanzi ngokubanzi ziyancipha ngokunyuka kwamaqondo obushushu, kodwa kumanqanaba athile obushushu, i-thermal gelation ingenzeka. Ukuqonda olu phawu kunokubaluleka okukhokelayo okubalulekileyo kwisicelo esisebenzayo kunye nokuphucula inkqubo ye-HPMC.
Ixesha lokuposa: Jul-10-2024