Hunhu hwemakemikari eHPMC

Hydroxypropyl Methylcellulose (HPMC)i non-ionic cellulose ether, inova chigadzirwa chakagadziriswa nemakemikari chinoumbwa nekuita kwe natural cellulose ne propylene oxide ne methyl chloride mushure mekugadziriswa kwe alkali. HPMC ine kugadzikana kwakanaka kwemuviri nemakemikari uye inoshandiswa zvakanyanya mumishonga, zvinhu zvekuvaka, chikafu, zvizoro nedzimwe nzvimbo. Hunhu hwayo hwemakemikari ndehwekuti:

1. Hunhu hwemaumbirwo emolekyulu

Mafupa ekutanga eHPMC anobva ku cellulose yechisikigo, iyo inoumbwa nemayuniti eglucose akabatana ne β-1,4-glycosidic bonds kuti agadzire linear macromolecular chain. Kuunzwa kwe hydroxypropyl ne methoxy groups kunotsiva zvishoma mapoka e hydroxyl (-OH) ari pa cellulose molecular chain, nokudaro ichipa hunhu hwakasiyana. Hunhu uhwu hwekutsiva (kureva, hunhu hwekutsiva methoxy ne hydroxypropyl groups) hune simba guru pakunyungudika, hunhu hwe gel uye kugadzikana kwe HPMC.

2. Kunyungudika

HPMC ipolymer isinganyungudike mumvura inogona kuzvimba nekukurumidza mumvura inotonhora uye inoumba mhinduro inopenya kana inopenya yecolloidal. Zvisinei, mumvura inopisa, HPMC haisi nyore kunyungudika uye inoumba gel pakupisa kwakanyanya. Hunhu hwegel iyi inodzoserwa mumhepo ndeimwe yehunhu hwakakosha hweHPMC. Pamusoro pemvura, HPMC inogonawo kunyungudika mune zvimwe zvinonyungudika zvepolar, zvakaita se solvent yakasanganiswa ye ethanol nemvura, dimethylformamide, nezvimwewo.

3. Kugadzikana kwekupisa uye gelation

HPMC ine kugadzikana kwakanaka kwekupisa. Sezvo tembiricha ichikwira, macheni emamolekyu eHPMC ari mumvura inoyerera achasangana nekubatana kwemvura kuti agadzire chimiro che network chine mativi matatu, uye kuchinja kubva pamhinduro kuenda kugel kuchaitika. Tembiricha yegelation inoenderana nehuwandu uye huremu hwemamolekyu ezvimwe zvinhu. Kazhinji, HPMC ine hydroxypropyl yakawanda ine tembiricha yepamusoro yegelation, nepo HPMC ine methoxy yakawanda ine tembiricha yakaderera yegelation.

Gelation inodzokororwa, uye gel inonyungudika zvakare kuita mvura mushure mekutonhora. Iyi thermogel yakasarudzika inoita kuti HPMC ishandiswe sechinhu chinogara kwenguva refu muindasitiri yemishonga uye inoshandiswa muindasitiri yezvinhu zvekuvaka kuvandudza mashandiro ekuvaka kwedhaka.

4. Kugadzikana kwepH

HPMC inochengetedza kugadzikana kwakanaka muhuwandu hwepH hwe3 ~ 11. Huwandu hwakakura hwepH hunobvumira kuti ishandiswe munzvimbo dzakasiyana-siyana pasina kuora kana kunaya kwemvura. Kana huwandu hwepH huri pasi pe3 kana kupfuura 11, mhinduro inogona kuderedzwa kana kudonha nekuda kwehuwandu hwakawanda hwehydrogen ions kana hydroxide ions, zvichikonzera kudzikira kwekushanda.

5. Kuchinja kwemakemikari

Nekuda kwekuvapo kwemamwe mapoka ehydroxyl asina kutsiviwa mu HPMC molecule, ichiri kuchengetedza chimwe chiitiko chemakemikari uye inogona kuita zvinotevera:

Kuita kweEsterification: Kana mamiriro ezvinhu akakodzera, HPMC inogona kuita neacyl chloride, anhydride, nezvimwewo kuti igadzire maester;

Maitiro eEtherification: Mapoka ehydroxyl akasara anogona kuramba achiita nema etherifying agents (akadai se epoxides) kuti awedzere kuchinja mwero wekutsiva uye mashandiro eHPMC;

Maitiro eOxidation: Kana paine ma oxidants akasimba (akadai se potassium permanganate, sodium hypochlorite), cheni yemamorekuru yeHPMC inogona kutyoka, zvichikonzera kudzikira kwe viscosity;

Kugadziriswa kweHydrolysis: Pasi pesimba remaacid akasimba kana mabhesi akasimba, macheni ehydroxypropyl nemethoxy anogona kusanganiswa nehydrolyzed, zvichikonzera shanduko muchimiro chemamorekuru uye kudzikira kwekushanda.

Kazhinji, kana zvakajairika pakushandisa, hunhu hwemakemikari eHPMC hwakagadzikana.

6. Kuora kwechinhu

HPMC inotorwa kubva mu cellulose yechisikigo, saka inogona kusvibiswa kuita shuga diki dzemamorekuru munzvimbo chaiyo yehupenyu (senge pasi pesimba rema microorganisms), uye pakupedzisira inoora kuita carbon dioxide nemvura. Kuora kwakanaka uku kunoita kuti HPMC ikwane zvinodiwa nezvinhu zvisina njodzi kunharaunda.

7. Kuenderana nezvimwe zvinhu

Sepolymer isiri ionic, HPMC inoenderana zvakanaka nezvimwe zvinhu zvinowedzerwa zve ionic kana zvisiri ionic (senge mamwe mapolymer, ma surfactants, ma thickeners, nezvimwewo). Kunyanya mu formulation system, inogona kushanda nezvinhu zvakasiyana-siyana zvinosanganisa mushonga, zvinovaka muviri, pigments, nezvimwewo pasina kunaya kwemvura kana kupatsanurwa.

Kugadzikana kweHPMC munzvimbo ine electrolyte yakawanda kuchakanganiswa, uye munyu wakawandisa we inorganic unogona kukonzera kuti viscosity yemushonga iderere kana kutoita kuti iite seyakapfava.

8. Kudzivirira ma enzyme

Zvichienzaniswa ne cellulose yechisikigo,HPMCYakawedzera simba rekudzivirira cellulase nekuda kwekutsiviwa kwemamwe mapoka ehydroxyl, uye haiparadzwe nyore nyore nema enzymes akajairika. Izvi zvinoita kuti ive mukana wekunonoka kuburitswa kwemishonga munzvimbo yemudumbu.

Hydroxypropyl methylcellulose (HPMC) chinhu chepolymer chakagadzirwa nemakemikari chine mvura inonyunguduka zvakanaka, kupisa kwakadzikama, pH yakagadzikana, makemikari akagadzikana uye kuora kwehupenyu. Nekuda kwechimiro chayo chakasiyana uye hunhu hwemakemikari, HPMC inoshandiswa zvakanyanya muminda yemishonga, zvinhu zvekuvaka, machira, chikafu, zvizoro, nezvimwewo, kunyanya mumafomu anoda kukora, kudzorwa, kugadzirwa kwefirimu, kumisa, emulsification nezvimwe.