I-HPMC (i-Hydroxypropyl Methylcellulose) yinto eqhelekileyo ye-semi-synthetic polysaccharide polymer esetyenziswa kakhulu kumayeza, ukutya, ishishini lemichiza kunye nezinye iinkalo. Iimpawu zayo zokuchithwa yenye yeendawo ezishushu kuphando kunye nokusetyenziswa.
1. Ubume bemolekyuli kunye neempawu zokunyibilika kwe-HPMC
I-HPMC yikhompawundi yepolymer enyibilikayo emanzini efunyenwe ngokuguqulwa kwe-etherification yeselulosi. Iyunithi yayo yesakhiwo yi-β-D-glucose, edibaniswe nge-1,4-glycosidic bonds. Isakhiwo esiphambili se-chain ye-HPMC sithathwe kwi-cellulose yendalo, kodwa inxalenye yamaqela ayo e-hydroxyl ithathelwe indawo ngamaqela e-methoxy (-OCH₃) kunye namaqela e-hydroxypropyl (-CH₂CH (OH)CH₃), ngoko ibonisa ukuziphatha kokuchithwa okungafaniyo ne-cellulose yendalo.
Ubume bemolekyuli ye-HPMC inefuthe elibonakalayo ekunyibilikeni kwayo. I-degree of substitution (i-DS, i-Degree of Substitution) kunye ne-molar substitution (MS, i-Molar Substitution) ye-HPMC yimilinganiselo ebalulekileyo emisela iimpawu zayo zokunyibilika. Ukuphakama kweqondo lokutshintshwa, amaqela amaninzi e-hydroxyl kwi-molecule athatyathwa ngamaqela e-hydrophobic methoxy okanye i-hydroxypropyl, eyandisa ukunyibilika kwe-HPMC kwizinyibilikisi zezinto eziphilayo kunye nokunciphisa ukunyibilika emanzini. Ngokuchasene noko, xa iqondo lokutshintshwa liphantsi, i-HPMC i-hydrophilic emanzini kwaye izinga lokuchithwa kwayo likhawuleza.
2. Indlela yokuchithwa kwe-HPMC
Ukunyibilika kwe-HPMC emanzini yinkqubo entsonkothileyo yomzimba kunye neekhemikhali, kwaye indlela yokupheliswa kwayo ibandakanya la manyathelo alandelayo:
Inqanaba lokumanzisa: Xa i-HPMC idibana namanzi, iimolekyuli zamanzi ziya kuqala zenze ifilimu ye-hydration kumphezulu we-HPMC ukusonga amasuntswana e-HPMC. Kule nkqubo, iimolekyuli zamanzi zisebenzisana ne-hydroxyl kunye namaqela e-methoxy kwiimolekyuli ze-HPMC ngokusebenzisa iibhondi ze-hydrogen, ezibangela ukuba iimolekyuli ze-HPMC zimanziswe ngokuthe ngcembe.
Inqanaba lokudumba: Ngokungena kweemolekyuli zamanzi, amasuntswana e-HPMC aqala ukufunxa amanzi kwaye adumbe, umthamo uyanda, kwaye amatyathanga eemolekyuli ngokuthe ngcembe akhulule. Ikhono lokudumba le-HPMC lichatshazelwa bubunzima bayo bemolekyuli kunye nezinto ezithatha indawo. Ubukhulu be-molecular weight, ixesha elide lokudumba; Ukuqina kwe-hydrophilicity ye-substitute, iqondo elikhulu lokudumba.
Inqanaba lokuchithwa: Xa iimolekyuli ze-HPMC zifunxa amanzi aneleyo, amakhonkco eemolekyuli aqala ukukhupha amasuntswana kwaye ngokuthe ngcembe asasazeke kwisisombululo. Isantya sale nkqubo sichatshazelwa yizinto ezifana nobushushu, izinga lokuvuselela kunye neempawu ze-solvent.
HPMC jikelele ibonisa ukunyibilika okulungileyo emanzini, ingakumbi kubushushu begumbi. Nangona kunjalo, kuyafaneleka ukuba uqaphele ukuba xa izinga lokushisa liphakama kwinqanaba elithile, i-HPMC iya kubonisa into ethi "i-gel thermal", oko kukuthi, i-solubility iyancipha njengoko iqondo lokushisa likhula. Oku kubangelwa ukunyakaza okuqinisiweyo kweemolekyuli zamanzi kumaqondo aphezulu okushisa kunye nokusebenzisana okuphuculweyo kwe-hydrophobic phakathi kwee-molecule ze-HPMC, ezikhokelela kumbutho we-intermolecular kunye nokwakhiwa kwesakhiwo se-gel.
3. Izinto ezichaphazela ukunyibilika kwe-HPMC
I-solubility ye-HPMC ichatshazelwa yimiba emininzi, kubandakanywa iimpawu zayo zomzimba kunye neekhemikhali kunye neemeko zangaphandle. Izinto eziphambili ziquka:
Iqondo lokutshintshwa: Njengoko kukhankanyiwe ngasentla, uhlobo kunye nenani lamalungu e-HPMC achaphazela ngqo ukunyibilika kwayo. Okukhona abathathi-nxaxheba abaninzi, amaqela ambalwa e-hydrophilic kwi-molecule kunye nokubi ngakumbi ukunyibilika. Ngokuchasene noko, xa kukho izinto ezibambeleyo ezimbalwa, i-hydrophilicity ye-HPMC iyaphuculwa kwaye ukunyibilika kungcono.
Ubunzima bemolekyuli: Ubunzima bemolekyuli ye-HPMC buhambelana ngokuthe ngqo nexesha layo lokuchithwa. Ubukhulu be-molecular weight, bucotha inkqubo yokutshatyalaliswa. Oku kungenxa yokuba ikhonkco lemolekyuli ye-HPMC enobunzima obukhulu bemolekyuli inde kwaye iimolekyuli zibambene ngokuqinileyo, zenza kube nzima ukuba iiamolekyuli zamanzi zingene, okukhokelela ekudumbeni kancinci kunye namazinga onyibiliko.
Ubushushu besisombululo: Ubushushu ngomnye wemiba ephambili echaphazela ukunyibilika kwe-HPMC. I-HPMC inyibilika ngokukhawuleza kumaqondo obushushu asezantsi, ngelixa kumaqondo obushushu aphezulu inokwenza ijeli kwaye inciphise ukunyibilika kwayo. Ngoko ke, i-HPMC idla ngokulungiswa emanzini obushushu obuphantsi ukuphepha i-gelation kumaqondo aphezulu.
Uhlobo lokunyibilika: I-HPMC ayinyibiliki kuphela emanzini, kodwa ikwanyibilika kwizinyibilikisi ezithile eziphilayo, njenge-ethanol, i-isopropyl alcohol, njl njl. Phantsi kweemeko eziqhelekileyo, i-HPMC inonyibiliko olulambathayo kwizinyibilikisi eziphilayo, kwaye isixa esifanelekileyo samanzi kufuneka sifakwe ukunceda ukunyibilika.
Ixabiso le-pH: I-HPMC inokunyamezela okuthile kwixabiso le-pH yesisombululo, kodwa phantsi kweemeko ze-asidi kunye neemeko ze-alkali, ukunyibilika kwe-HPMC kuya kuchaphazeleka. Ngokubanzi, i-HPMC inonyibiliko olungcono kuluhlu lwe-pH lwe-3 ukuya kwi-11.
4. Ukusetyenziswa kweHPMC kwiinkalo ezahlukeneyo
Ukunyibilika kwe-HPMC kwenza ukuba luncedo kwiindawo ezininzi:
Intsimi yamachiza: I-HPMC isetyenziswa ngokuqhelekileyo njengezinto zokugquma, izinto zokuncamathelisa kunye nee-arhente ezizinzileyo zokukhupha iipilisi zamayeza. Kwiingubo zamachiza, i-HPMC inokwenza ifilimu efanayo yokuphucula ukuzinza kwechiza; kwimixube yokukhutshwa okuzinzileyo, i-HPMC ilawula izinga lokukhutshwa kwechiza ngokulawula izinga lokuchithwa kwechiza, ngaloo ndlela ifezekisa ukuhanjiswa kwechiza okuhlala ixesha elide.
Ishishini lokutya: Ekutyeni, i-HPMC isetyenziswa njenge-thickener, emulsifier kunye ne-stabilizer. Ngenxa yokuba i-HPMC inonyibiliko olulungileyo lwamanzi kunye nokuzinza kobushushu, inokubonelela ngobume obufanelekileyo kunye nencasa kwiintlobo ezahlukeneyo zokutya. Kwangaxeshanye, ubume be-HPMC obungeyiyo i-ionic buyithintela ekuphenduleni kunye nezinye izithako zokutya kunye nokugcina ukuzinza komzimba kunye neekhemikhali zokutya.
Umzi-mveliso wemichiza wemihla ngemihla: I-HPMC isoloko isetyenziswa njenge-thickener kunye ne-emulsifier kwiimveliso ezifana neshampu, i-conditioner kunye ne-cream yobuso. Ukunyibilika kwayo okulungileyo emanzini kunye nesiphumo sokutyeba kwenza ukuba ibonelele ngamava osetyenziso agqwesileyo. Ukongeza, i-HPMC inokunxibelelana nezinye izithako ezisebenzayo ukuphucula ukusebenza kwemveliso.
Izinto zokwakha: Kushishino lokwakha, i-HPMC isetyenziswa njenge-thickener kunye ne-ejenti yokugcina amanzi kwiimbumba zesamente, i-adhesives tile kunye neengubo. I-HPMC inokuphucula ngokufanelekileyo ukusebenza kwezi zixhobo, ukwandisa ixesha labo lokusetyenziswa, kunye nokuphucula ukuxhathisa ukuqhekeka.
Njengesixhobo se-polymer esine-solubility efanelekileyo, i-HPMC's dissolution behavior ichaphazeleka kwizinto ezininzi, ezifana nesakhiwo se-molecular, ubushushu, ixabiso le-pH, njl. Kwiinkalo ezahlukeneyo zesicelo, i-solubility ye-HPMC inokulungiswa ngokulungelelanisa le miba ukuhlangabezana neemfuno ezahlukeneyo. I-solubility ye-HPMC ayigxininisi kuphela ukusebenza kwayo kwizisombululo ezinamanzi, kodwa ichaphazela ngokuthe ngqo imisebenzi yayo kumashishini amayeza, ukutya, imichiza yemihla ngemihla kunye nokwakhiwa.
Ixesha lokuposa: Oct-14-2024