Izifundo zeRheological zeHydroxypropyl Methylcellulose (HPMC) ezityebileyo kwiinkqubo zibalulekile ekuqondeni ukuziphatha kwazo kwizicelo ezahlukeneyo, ukusuka kumayeza ukuya ekutyeni nakwizithambiso. I-HPMC yi-cellulose ether derivative esetyenziswa ngokubanzi njenge-ejenti yokuqina, i-stabilizer, kunye ne-emulsifier ngenxa yokukwazi ukuguqula iimpawu ze-rheological zezisombululo kunye nokumiswa.
1.Imilinganiselo yeViscosity:
I-Viscosity yenye yezona zinto zibalulekileyo ze-rheological properties ezifundwe kwiinkqubo ze-HPMC. Iindlela ezahlukeneyo ezifana ne-viscometry ejikelezayo, i-capillary viscometry, kunye ne-oscillatory rheometry zisetyenziselwa ukulinganisa i-viscosity.
Ezi zifundo zicacisa isiphumo sezinto ezinje ngoxinaniso lwe-HPMC, ubunzima bemolekyuli, iqondo lokutshintsha, ubushushu, kunye nesantya sokucheba kwi-viscosity.
Ukuqonda i-viscosity kubalulekile njengoko imisela indlela yokuziphatha, uzinzo, kunye nokufaneleka kokusetyenziswa kweenkqubo ezityebileyo ze-HPMC.
2.Ukucheba-Ukuziphatha:
Izisombululo ze-HPMC zidla ngokubonisa ukuziphatha kokucheba, okuthetha ukuba i-viscosity yabo iyancipha ngokunyuka kwesantya sokucheba.
Izifundo zeRheological zijonga kubungakanani bokuchetywa kwe-chear kunye nokuxhomekeka kwayo kwizinto ezinje ngoxinaniso lwepolymer kunye nobushushu.
Ukulinganisa ukuziphatha kwe-shear-thinning kubalulekile kwizicelo ezifana neengubo kunye ne-adhesives, apho ukuhamba ngexesha lesicelo kunye nokuzinza emva kokusetyenziswa kubaluleke kakhulu.
3.Thixotropy:
Thixotropy ibhekisela kwixesha elixhomekeke kwixesha lokubuyiswa kwe-viscosity emva kokususwa koxinzelelo lwe-shear. Iinkqubo ezininzi ze-HPMC zibonisa ukuziphatha kwethixotropic, okuluncedo kwizicelo ezifuna ukuhamba okulawulwayo kunye nokuzinza.
Izifundo ze-Rheological zibandakanya ukulinganisa ukubuyiswa kwe-viscosity ekuhambeni kwexesha emva kokubeka inkqubo kuxinzelelo lokucheba.
Ukuqonda uncedo lwe-thixotropy ekuqulunqeni iimveliso ezifana neepende, apho ukuzinza ngexesha lokugcinwa kunye nokulula kwesicelo kubalulekile.
4.Gelation:
Kwiindawo eziphezulu okanye ngezongezo ezithile, izisombululo ze-HPMC zinokungena kwi-gelation, zenze isakhiwo senethiwekhi.
Izifundo zeRheological ziphanda indlela yokuziphatha kwe-gelation malunga nezinto ezinje ngoxinaniso, ubushushu, kunye ne-pH.
Izifundo ze-Gelation zibalulekile ekuyileni ukuqulunqwa kweziyobisi ezizinzileyo kunye nokudala iimveliso ezizinzile ezisekwe kwijeli kumashishini okutya kunye nokhathalelo lomntu.
5.Ubume boLwakhiwo:
Ubuchwephesha obufana ne-X-ray encinci ye-X-ray (SAXS) kunye ne-rheo-SAXS ibonelela ngengqiqo kwi-microstructure yeenkqubo ze-HPMC.
Olu phononongo lutyhila ulwazi malunga ne-polymer chain conformation, i-aggregation behaviour, kunye nokunxibelelana neemolekyuli ezinyibilikayo.
Ukuqonda imiba yolwakhiwo kunceda ekuqikeleleni indlela yokuziphatha kwe-rheological macroscopic kunye nokuphucula imiqulu yeepropathi ezifunwayo.
I-6.Dynamic Mechanical Analysis (DMA):
I-DMA ilinganisa iimpawu ze-viscoelastic zezinto eziphantsi kwe-oscillatory deformation.
Izifundo zeRheological zisebenzisa i-DMA zicacisa iiparamitha ezifana nemodyuli yokugcina (G'), imodyuli yokulahleka (G”), kunye ne-viscosity entsonkothileyo njengomsebenzi wokuphindaphinda kunye nobushushu.
I-DMA iluncedo kakhulu ekuphawuleni ukuziphatha okuqinileyo nokufana nolwelo lweejeli kunye neepastes zeHPMC.
7.Izifundo eziNxibelele ngeSicelo:
Izifundo ze-Rheological zilungelelaniswe kwizicelo ezithile ezifana neepilisi zamachiza, apho i-HPMC isetyenziswa njenge-binder, okanye kwiimveliso zokutya ezifana neesosi kunye nempahla yokunxiba, apho isebenza njenge-thickener kunye ne-stabilizer.
Olu phononongo luphucula ukwakheka kwe-HPMC kwiipropati ezinqwenelekayo zokuhamba, ukuthungwa, kunye nokuzinza kweshelufu, ukuqinisekisa ukusebenza kwemveliso kunye nokwamkelwa kwabathengi.
izifundo rheological zidlala indima ebalulekileyo ekuqondeni ukuziphatha entsonkothileyo iinkqubo HPMC thickener. Ngokucacisa i-viscosity, i-shear-thinning, i-thixotropy, i-gelation, iimpawu zolwakhiwo, kunye neempawu ezithe ngqo kwisicelo, ezi zifundo ziququzelela uyilo kunye nokwenza ngcono ukwakheka okusekwe kwi-HPMC kuwo wonke amashishini ahlukeneyo.
Ixesha lokuposa: May-10-2024