Chii chinonzi Hydroxypropyl Methylcellulose Yakagadzirwa Kubva

Hydroxypropyl methylcellulose (HPMC) is semisynthetic polymer inoshandiswa mumaindasitiri akasiyana siyana, anosanganisira kuvaka, chikafu, mishonga, uye zvigadzirwa zvekuchengeta munhu. Inokosheswa nekukwanisa kwayo kuvandudza rheological maitiro ekugadzirisa, pamwe nekuenderana kwayo nezvimwe zvinoshandiswa uye yakaderera toxicity. Kuti unzwisise kuti HPMC inogadzirwa sei, zvakakosha kutanga wanzwisisa chimiro uye zvimiro zve cellulose.

Cellulose iketani refu yemamorekuru eglucose inowanikwa mumadziro emiti. Mamorekuru eglucose anobatanidzwa pamwechete ne beta-1,4-glycosidic bond, achigadzira mutsara wetani. Cheni dzinobva dzabatwa pamwe chete nehydrogen bond uye mauto eVan der Waals kuti aumbe zvimiro zvakasimba, zvine fibrous. Cellulose ndiyo yakanyanya kuwanda pasi pano, uye inoshandiswa mumhando dzakasiyana siyana dzekushandisa, kusanganisira mapepa, machira, uye zvekuvakisa.

Nepo cellulose iine zvinhu zvakawanda zvinobatsira, inowanzoomesesa uye isinganyungudika kuti ishandiswe mune akawanda magadzirirwo. Kuti vakunde zvipingamupinyi izvi, masayendisiti akagadzira akati wandei akagadziridzwa cellulose derivatives, kusanganisira HPMC. HPMC inogadzirwa nekugadzirisa yakasikwa cellulose kuburikidza nenhevedzano yemakemikari maitiro.

Nhanho yekutanga mukugadzira HPMC ndeyekuwana iyo cellulose yekutanga zvinhu. Izvi zvinogona kuitwa nekubvisa cellulose kubva muzvirimwa zvakaita sehuni pulp, donje, kana bamboo. Iyo cellulose inobva yabatwa nealkaline solution, yakadai sesodium hydroxide kana potassium hydroxide, kubvisa tsvina uye kuputsa fiber cellulose kuita zvidimbu zviduku. Iyi nzira inozivikanwa se mercerization, uye inoita kuti cellulose iwedzere kushanda uye nyore kugadzirisa.

Mushure memercerization, cellulose inobatwa nemusanganiswa wepropylene oxide uye methyl chloride kuunza hydroxypropyl uye methyl mapoka kumusana we cellulose. Iwo mapoka e-hydroxypropyl anowedzerwa kuti avandudze kunyungudika uye kuchengetwa kwemvura zvimiro zveselulosi, nepo mapoka emethyl anowedzerwa kuti awedzere kugadzikana uye kuderedza reactivity ye cellulose. Mhedzisiro yacho inowanzoitwa pamberi pechinhu chinokonzeresa, senge sodium hydroxide kana potassium hydroxide, uye pasi pekudzora mamiriro ekushisa, kudzvanywa, uye nguva yekuita.

Iyo dhigirii yekutsiva (DS) yeHPMC inoreva huwandu hwehydroxypropyl uye methyl mapoka anounzwa pane cellulose musana. Iyo DS inogona kusiyana zvichienderana neinodiwa zvivakwa zveHPMC uye chaiyo application yairi kushandiswa. Kazhinji, hunhu hweDS hwepamusoro hunoita kuti HPMC ine viscosity yakaderera uye kukurumidza kunyungudika mwero, nepo kushomeka kweDS kunoguma neHPMC ine viscosity yakakwirira uye inononoka kunyungudika mitengo.

Mushure mekuita kwapera, chigadzirwa chinobva chacheneswa uye chakaomeswa kugadzira HPMC poda. Maitiro ekucheneswa anosanganisira kubvisa chero makemikari asina kubatwa, zvisaririra zvinonyungudutsa, uye kumwe kusvibiswa kubva kuHPMC. Izvi zvinowanzoitwa kuburikidza nemusanganiswa wekugeza, kusefa, uye kuomesa matanho.

Chigadzirwa chekupedzisira ihupfu huchena kusvika kune-chena husina hwema uye husina kunaka. HPMC inonyungudika mumvura uye yakawanda organic solvents, uye inogona kugadzira gels, mafirimu, uye zvimwe zvimiro zvinoenderana nemamiriro ekushandiswa. Iyo isiri-ionic polymer, zvichireva kuti haitakure chero chaji yemagetsi, uye inowanzoonekwa seisina chepfu uye yakachengeteka kushandiswa mumhando dzakasiyana dzekushandisa.

HPMC inoshandiswa mumhando dzakasiyana-siyana dzekugadzira, kusanganisira pendi, zvinonamira, zvisimbiso, mishonga, uye zvigadzirwa zvekudya. Mukushanda kwekuvaka, HPMC inowanzo shandiswa seyakakora, binder, uye firimu-yaimbova mune simende uye gypsum-based zvigadzirwa, senge madhaka, grouts, uye majoini makomisheni.