IHydroxypropyl methylcellulose (HPMC) yikhompawundi yepolymer enyibilikayo emanzini esetyenziswa kakhulu kumayeza, ukutya, izinto zokwakha kunye nezinye iindawo. Ngenxa yokuqina kwayo okulungileyo, ukwenza ifilimu, i-emulsifying, i-bonding kunye nezinye iipropati, isetyenziswa ngokubanzi njenge-thickener, i-stabilizer kunye ne-agent yokumisa. Iimpawu ze-rheological ze-HPMC, ngokukodwa ukusebenza kwayo kumaqondo okushisa ahlukeneyo, zizinto ezibalulekileyo ezichaphazela umphumo wesicelo.
1. Isishwankathelo se-HPMC Rheological Properties
Iimpawu ze-Rheological ziyimbonakaliso ebanzi yokuguqulwa kunye neempawu zokuhamba kwezinto eziphantsi kwamandla angaphandle. Kwimathiriyeli yepolymer, i-viscosity kunye ne-shear thinning behavior zezona parameters zixhaphakileyo zerheological. Iimpawu ze-rheological ze-HPMC zichatshazelwa ikakhulu yimiba efana nobunzima bemolekyuli, ugxininiso, iipropati zokunyibilikisa kunye nobushushu. Njenge-ether ye-cellulose engeyona i-ionic, i-HPMC ibonisa i-pseudoplasticity kwisisombululo samanzi, oko kukuthi, i-viscosity yayo iyancipha ngokunyuka kwesantya sokucheba.
2. Impembelelo yoBubushushu kwi-HPMC Viscosity
Ubushushu yenye yezinto eziphambili ezichaphazela iimpawu rheological of HPMC. Njengoko ubushushu buyanyuka, i-viscosity yesisombululo se-HPMC idla ngokuncipha. Oku kungenxa yokuba ukunyuka kwamaqondo obushushu kunciphisa intsebenziswano ye-hydrogen bond phakathi kweemolekyuli zamanzi, ngaloo ndlela kunciphisa amandla okunxibelelana phakathi kwamatyathanga eemolekyuli e-HPMC, okwenza amatyathanga emolekyuli abe lula ukutyibilika nokuhamba. Ke ngoko, kumaqondo obushushu aphezulu, izisombululo ze-HPMC zibonisa i-viscosity esezantsi.
Nangona kunjalo, utshintsho lwe-viscosity lwe-HPMC alukho ubudlelwane bomgca. Xa ubushushu bunyuka ukuya kumlinganiselo othile, i-HPMC inokungena kwinkqubo yokunyibilika kwemvula. Kwi-HPMC, ubudlelwane phakathi kwe-solubility kunye nobushushu bunzima ngakumbi: ngaphakathi koluhlu oluthile lobushushu, i-HPMC iya kudlula kwisisombululo, esibonakaliswa ngokunyuka okubukhali kwi-viscosity yesisombululo okanye ukubunjwa kwejel. Lo mcimbi uqhele ukwenzeka xa isondela okanye idlula ubushushu bokupheliswa kwe-HPMC.
3. Impembelelo yokushisa kwindlela yokuziphatha ye-rheological yesisombululo se-HPMC
Ukuziphatha kwe-rheological yesisombululo se-HPMC ngokuqhelekileyo kubonisa i-shear-thinning effect, oko kukuthi, i-viscosity iyancipha xa izinga lokucheba linyuka. Utshintsho kwiqondo lobushushu lunempembelelo ebalulekileyo kule mpembelelo yokucheba. Ngokubanzi, njengoko ubushushu bukhula, i-viscosity yesisombululo se-HPMC iyancipha, kwaye umphumo wayo wokucheba ubonakala ngakumbi. Oku kuthetha ukuba kumaqondo okushisa aphezulu, i-viscosity yesisombululo se-HPMC ixhomekeke ngakumbi kwizinga lokucheba, oko kukuthi, kwinqanaba elifanayo lokucheba, isisombululo se-HPMC kwiqondo lokushisa eliphezulu lihamba ngokulula ngakumbi kunokushisa okuphantsi.
Ukongezelela, ukunyuka kweqondo lokushisa kuchaphazela i-thixotropy yesisombululo se-HPMC. Thixotropy ibhekisela kwipropati ukuba i-viscosity yesisombululo iyancipha phantsi kwesenzo samandla okucheba, kwaye i-viscosity iyancipha ngokuthe ngcembe emva kokuba i-shear force isusiwe. Ngokuqhelekileyo, ukunyuka kweqondo lokushisa kukhokelela ekunyuseni kwe-thixotropy yesisombululo se-HPMC, oko kukuthi, emva kokuba i-shear force isusiwe, i-viscosity iphinda ibuyele kancinci kuneemeko zokushisa eziphantsi.
4. Impembelelo yobushushu kwindlela yokuziphatha ye-gelation ye-HPMC
I-HPMC inepropati ekhethekileyo ye-thermal gelation, oko kukuthi, emva kokufudumeza kwiqondo elithile lobushushu (ubushushu be-gel), isisombululo se-HPMC siya kutshintsha ukusuka kwimeko yesisombululo ukuya kwi-gel state. Le nkqubo ichaphazeleka kakhulu ngubushushu. Njengoko iqondo lokushisa lisanda, intsebenziswano phakathi kwe-hydroxypropyl kunye ne-methyl substituents kwiimolekyuli ze-HPMC ziyanda, okukhokelela ekubanjweni kwamatyathanga eemolekyuli, ngaloo ndlela zenza ijeli. Le nto ibaluleke kakhulu kumashishini amayeza kunye nokutya kuba ingasetyenziselwa ukulungelelanisa ukuthungwa kunye nokukhulula iimpawu zemveliso.
5. Ukusetyenziswa kunye nentsingiselo ebonakalayo
Impembelelo yobushushu kwiipropati ze-rheological ze-HPMC zibaluleke kakhulu kwizicelo eziphathekayo. Kuba isicelo izisombululo HPMC, ezifana amalungiselelo iziyobisi ezinzileyo-ukukhululwa, thickeners ukutya, okanye abalawuli izinto zokwakha, isiphumo lobushushu kwiipropati rheological kufuneka ziqwalaselwe ukuqinisekisa uzinzo kunye nokusebenza imveliso phantsi kweemeko ezahlukeneyo lobushushu. Umzekelo, xa ulungiselela amachiza ajongana nobushushu, isiphumo sokutshintsha kobushushu kwi-viscosity kunye nokuziphatha kwe-gelation ye-matrix ye-HPMC kufuneka ithathelwe ingqalelo ukunyusa izinga lokukhutshwa kwechiza.
Ubushushu bunempembelelo ebalulekileyo kwiipropati ze-rheological ze-hydroxypropyl methylcellulose. Ukunyuka kwamaqondo obushushu ngokuqhelekileyo kunciphisa i-viscosity yezisombululo ze-HPMC, kwandisa i-shear-thinning effect kunye ne-thixotropy, kwaye kunokubangela i-thermal gelation. Kwizicelo eziphathekayo, ukuqonda kunye nokulawula umphumo weqondo lokushisa kwiipropati ze-rheological ze-HPMC ngundoqo wokuphucula ukusebenza kwemveliso kunye neeparitha zenkqubo.
Ixesha lokuposa: Sep-05-2024