IHydroxypropyl methylcellulose (HPMC) iyi-semi-synthetic, i-polymer encibilika emanzini etholakala ku-cellulose. Isetshenziswa kakhulu ezimbonini ezahlukahlukene, kufaka phakathi ezemithi, ukudla, ezokwakha, nezimonyo, ngenxa yezakhiwo zayo ezihlukile njengokujiya, ukubopha, ukwenza amafilimu, kanye nokusimamisa. Kodwa-ke, kubalulekile ukuqaphela ukuthi i-HPMC ayinayo indawo ethile yokuncibilika ngenxa yokuthi ayingeni inqubo yeqiniso yokuncibilika njengezinto zecrystalline. Kunalokho, iba nenqubo yokuwohloka kokushisa lapho ishiswa.
1. Izakhiwo ze-HPMC:
I-HPMC iyimpushana engenaphunga emhlophe kuya kokumhlophe, encibilika emanzini kanye nezincibilikisi eziningi eziphilayo. Izici zayo ziyahlukahluka kuye ngezinto ezifana nezinga lokushintshwa (DS), isisindo samangqamuzana, nokusabalalisa usayizi wezinhlayiyana. Ngokuvamile, ibonisa izici ezilandelayo:
Imvelo engeyona i-ionic: I-HPMC ayithwali noma iyiphi ishaji kagesi ngesisombululo, iyenza ihambisane nenhlobonhlobo yezinye izinto.
Ukwakhiwa kwefilimu: I-HPMC ingakha amafilimu acacile, aguqukayo uma omile, athola izinhlelo zokusebenza kuma-coatings, amafilimu, nasemafomini emithamo yokukhishwa okulawulwayo kwezemithi.
I-ejenti ejiyayo: Inikeza i-viscosity ezixazululweni, iyenze ibe wusizo emikhiqizweni yokudla, izimonyo, kanye nemithi.
I-Hydrophilic: I-HPMC inobudlelwane obuphezulu bamanzi, okufaka isandla ekuncibilikeni kwayo kanye nezakhiwo zefilimu.
2. Ukuhlanganiswa kwe-HPMC:
I-HPMC ihlanganiswa ngochungechunge lokusabela kwamakhemikhali okubandakanya i-cellulose, i-propylene oxide, ne-methyl chloride. Inqubo ihilela ukufakwa kwe-cellulose nge-propylene oxide elandelwa i-methylation ne-methyl chloride. Izinga lokushintsha (DS) le-hydroxypropyl namaqembu e-methoxy lingalawulwa ukuze kulungiselelwe izakhiwo ze-HPMC ewumphumela.
3. Izicelo ze-HPMC:
Imboni yezokwenziwa kwemithi: I-HPMC isetshenziswa kakhulu njenge-excipient ekwenziweni kwemithi, okuhlanganisa amaphilisi, amaphilisi, izixazululo ze-ophthalmic, namafomu emithamo yokukhishwa okulawulwayo.
Imboni yokudla: Isetshenziswa njenge-thickener, stabilizer, kanye ne-emulsifier emikhiqizweni yokudla efana namasoso, amasobho, ama-ayisikhilimu, nezinto zokubhaka.
Imboni yezokwakha: I-HPMC yengezwa emikhiqizweni esekwe kusimende ukuthuthukisa ukusebenza, ukugcinwa kwamanzi, nokunamathela. Ibuye isetshenziswe kuma-adhesives amathayili, ama-mortars, nama-renders.
Imboni yezimonyo: I-HPMC isetshenziswa ekwakhiweni kwezimonyo okuhlukahlukene okufana nokhilimu, izinto zokuthambisa, nama-shampoos ngokuqina kwayo kanye nezakhiwo zayo zokuzinzisa.
4. Ukuziphatha Okushisayo kwe-HPMC:
Njengoba kushiwo ngaphambili, i-HPMC ayinayo indawo ethile yokuncibilika ngenxa yemvelo yayo ye-amorphous. Kunalokho, ithola ukuwohloka kokushisa lapho ishiswa. Inqubo yokuwohloka ihilela ukugqashuka kwezibopho zamakhemikhali ngaphakathi kweketango le-polymer, okuholela ekwakhekeni kwemikhiqizo yokubola eguquguqukayo.
Izinga lokushisa lokuwohloka kwe-HPMC lincike ezintweni ezimbalwa, okuhlanganisa isisindo sayo samangqamuzana, izinga lokushintshwa, kanye nokuba khona kwezithasiselo. Ngokuvamile, ukuwohloka kokushisa kwe-HPMC kuqala cishe ku-200°C futhi kuqhubekela phambili ngezinga lokushisa elikhulayo. Iphrofayili yokonakaliswa ingahluka kakhulu ngokuya ngebanga elithile le-HPMC nezinga lokushisa.
Ngesikhathi sokuwohloka kokushisa, i-HPMC ibhekana nezinqubo eziningana ezihambisanayo, okuhlanganisa ukuphelelwa amanzi emzimbeni, ukuchithwa kwe-depolymerization, nokubola kwamaqembu asebenzayo. Imikhiqizo eyinhloko yokubola ihlanganisa amanzi, isikhutha, i-carbon monoxide, i-methanol, nama-hydrocarbon ahlukahlukene.
5. Amasu okuhlaziya okushisayo kwe-HPMC:
Ukuziphatha okushisayo kwe-HPMC kungafundwa kusetshenziswa amasu ahlukahlukene okuhlaziya, okuhlanganisa:
Ukuhlaziywa kwe-Thermogravimetric (TGA): I-TGA ikala ukwehla kwesisindo sesampula njengomsebenzi wezinga lokushisa, ihlinzeka ngolwazi mayelana nokuzinza kwayo kokushisa kanye ne-kinetics yokubola.
I-Differential scanning calorimetry (DSC): I-DSC ikala ukugeleza kokushisa kungene noma kuphume kusampula njengomsebenzi wezinga lokushisa, okuvumela ukuchazwa koshintsho lwesigaba kanye nemicimbi yokushisa efana nokuncibilika nokuwohloka.
I-Fourier-transform infrared spectroscopy (FTIR): I-FTIR ingasetshenziselwa ukuqapha izinguquko zamakhemikhali ku-HPMC ngesikhathi sokuwohloka kokushisa ngokuhlaziya izinguquko emaqenjini asebenzayo kanye nesakhiwo samangqamuzana.
6. Isiphetho:
I-HPMC iyi-polymer eguquguqukayo enezinhlobonhlobo zezicelo kwezemithi, ukudla, ukwakhiwa, nezimonyo. Ngokungafani nezinto ezicwebezelayo, i-HPMC ayinayo indawo ethile yokuncibilika kodwa ithola ukuwohloka kokushisa lapho ishiswa. Izinga lokushisa lokuwohloka lincike ezintweni ezihlukahlukene futhi ngokuvamile liqala cishe ku-200 ° C. Ukuqonda ukuziphatha okushisayo kwe-HPMC kubalulekile ekuphatheni nasekucutshungulweni kwayo okufanele ezimbonini ezahlukene.
Isikhathi sokuthumela: Mar-09-2024