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Ukulungiswa nokusetshenziswa kwe-hydroxypropyl methylcellulose

IHydroxypropyl methylcellulose (Hypromellose), eyaziwa nangokuthi i-hypromellose, iyimpushana ye-cellulose emhlophe ukuya kokumhlophe noma i-granule, enezici zokuncibilika emanzini abandayo futhi ayincibiliki emanzini ashisayo afana ne-methyl cellulose. Iqembu le-hydroxypropyl kanye neqembu le-methyl kuhlanganiswe neringi ye-glucose ye-anhydrous ye-cellulose nge-ether bond, okuwuhlobo lwe-non-ionic cellulose exutshwe i-ether. I-semisynthetic, engasebenzi, i-viscoelastic polymer evame ukusetshenziswa njengesithambiso ku-ophthalmology, noma njengesamukeli noma imoto emithini yomlomo.

ukulungiselela
I-pulp yeshidi le-kraft paper pulp etholwe ku-pine wood enokuqukethwe kwe-alpha cellulose okungama-97%, i-viscosity yangaphakathi engu-720 ml/g, kanye nesilinganiso sobude be-fiber engu-2.6 mm yacwiliswa kusixazululo samanzi se-NaOH esingu-49% ku-40°C. imizuzwana engu-50; i-pulp eyaba khona yabe isikhanywa ukuze kukhishwe i-NaOH enamanzi engaphezu kuka-49% ukuze kutholwe i-alkali cellulose. Isilinganiso sesisindo (49% se-NaOH isisombululo samanzi) kuya (okuqukethwe okuqinile ku-pulp) esinyathelweni sokukhulelwa sasingu-200. Isilinganiso sesisindo (okuqukethwe kwe-NaOH ku-alkali cellulose etholwe ngaleyo ndlela) kanye (okuqukethwe okuqinile ku-pulp) 1.49. I-alkali cellulose etholwe ngaleyo ndlela (20 kg) yafakwa ku-reactor enejakhethi enokunyakaziswa kwangaphakathi, bese ikhishwa futhi ihlanzwe nge-nitrogen ukuze kukhishwe umoya-mpilo owanele kureactor. Okulandelayo, ukunyakazisa kwangaphakathi kwenziwa ngenkathi kulawulwa izinga lokushisa ku-reactor ukuya ku-60°C. Khona-ke, kwengezwa u-2.4 kg we-dimethyl ether, futhi izinga lokushisa ku-reactor lalawulwa ukuze ligcinwe ku-60°C. Ngemva kokungeza i-dimethyl ether, engeza i-dichloromethane ukuze isilinganiso se-molar ye (dichloromethane) kuya (ingxenye ye-NaOH ku-alkaline cellulose) sibe ngu-1.3, bese wengeza i-propylene oxide ukuze wenze (i-propylene oxide) kanye (ku-pulp) Isilinganiso sesisindo sokuqukethwe okuqinile) yashintshwa yaba ngu-1.97, kuyilapho izinga lokushisa esikhunjeni lilawulwa lisuka ku-60°C laya ku-80°C. Ngemva kokwengezwa kwe-methyl chloride ne-propylene oxide, izinga lokushisa ku-reactor lalawulwa ukusuka ku-80°C kuya ku-90°C. Ngaphezu kwalokho, ukusabela kwaqhubeka ku-90 ° C imizuzu engu-20. Khona-ke, igesi yakhishwa ku-reactor, kwase kukhishwa i-hydroxypropyl methylcellulose engahluziwe ku-reactor. Izinga lokushisa le-hydroxypropyl methylcellulose engahluziwe ngesikhathi likhishwa lalingama-62 degreesC. Ukunqwabelana kuka-50% kasayizi wezinhlayiyana ekusabalaliseni kosayizi wezinhlayiyana ngokusekelwe esisindweni esiqoqwe esinqunywa ngokusekelwe esilinganisweni se-hydroxypropyl methylcellulose engahluziwe edlula ezimbotsheni zezisefo ezinhlanu, isisefo ngasinye esinosayizi wokuvula ohlukile, kukalwa. Ngenxa yalokho, isilinganiso sobukhulu bezinhlayiyana zezinhlayiya ezimahhadla kwaba ngu-6.2 mm. I-hydroxypropyl methylcellulose engahluziwe etholwe ngaleyo ndlela yethulwa ku-biaxial kneader eqhubekayo (KRC kneader S1, L/D=10.2, ivolumu yangaphakathi engu-0.12 amalitha, isivinini sokujikeleza esingu-150 rpm) ngenani lika-10 kg/h, futhi ukubola kwatholakala. i-hydroxypropyl methylcellulose engahluziwe. Isilinganiso sikasayizi wezinhlayiyana sasingu-1.4 mm njengoba kukalwa ngokufanayo kusetshenziswa izisefu ezinosayizi abahlukene bokuvula abangu-5. Ku-hydroxypropyl methylcellulose ebolile ethangini elinokulawula izinga lokushisa kwejakhethi, engeza amanzi ashisayo ku-80°C ngenani elizokwenza ukuthi (Isilinganiso sesisindo senani le-cellulose) sibe (inani eliphelele le-slurry) sishintshelwe ku-0.1, futhi kutholwe udaka. I-slurry yashukunyiswa ekushiseni okungashintshi okungama-80 ° C imizuzu engama-60. Okulandelayo, i-slurry yafakwa kusihlungi se-rotary pressure preheated (umkhiqizo we-BHS-Sonthofen) ngesivinini sokujikeleza esingu-0.5 rpm. Izinga lokushisa le-slurry lalingu-93°C. I-slurry yanikezwa kusetshenziswa iphampu, futhi ukucindezela kokukhipha kwepompo kwakungu-0.2 MPa. Usayizi wokuvula wesihlungi se-rotary pressure filter yayingu-80 μm, futhi indawo yokuhlunga yayiyi-0.12 m 2. Udaka olunikezwa isihlungi se-rotary pressure luguqulwa lube ikhekhe lokuhlunga ngokuhlunga ngesihlungi. Ngemva kokunikeza isitimu esingu-0.3 MPa ekhekheni elitholwe ngaleyo ndlela, amanzi ashisayo angu-95°C anikezwa ngenani kangangokuthi isilinganiso sesisindo (samanzi ashisayo) kuya (okuqukethwe okuqinile kwe-hydroxypropyl methylcellulose ngemva kokugeza) kwaba ngu-10.0, Bese, hlunga ngokusebenzisa isihlungi. Amanzi ashisayo anikezwa iphampu ngokucindezela kokukhipha okungu-0.2 MPa. Ngemva kokunikezwa kwamanzi ashisayo, umusi we-0.3 MPa wanikezwa. Khona-ke, umkhiqizo ogeziwe endaweni yokuhlunga ukhishwa nge-scraper futhi ukhishwe emshinini wokuwasha. Izinyathelo ezisuka ekuphakeleni i-slurry ukuya ekukhipheni umkhiqizo ohlanziwe ziqhutshwa ngokuqhubekayo. Njengomphumela wokulinganisa kusetshenziswa i-hygrometer yohlobo lokomisa ukushisa, okuqukethwe kwamanzi omkhiqizo owashiwe ngaleyo ndlela kwakungama-52.8%. Umkhiqizo owashwayo okhishwe kusihlungi se-rotary pressure womiswa kusetshenziswa umshini wokomisa umoya ongu-80° C., futhi wacolwa emshinini wokugaya i-Victory Mill ukuze kutholwe i-hydroxypropyl methylcellulose.

isicelo
Lo mkhiqizo usetshenziswa njenge-thickener, dispersant, binder, emulsifier kanye ne-stabilizer embonini yendwangu. Ibuye isetshenziswe kabanzi kuma-synthetic resin, i-petrochemical, izitsha zobumba, iphepha, isikhumba, imithi, ukudla, izimonyo nezinye izimboni.


Isikhathi sokuthumela: Nov-15-2022
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