HEC hauv kev lag luam coatings

Hydroxyethyl cellulose (HEC)yog ib qho khoom siv polymer uas tsis yog ionic uas yaj tau hauv dej, uas tau npaj los ntawm kev kho cov cellulose ntuj nrog alkali thiab reacting nrog ethylene oxide. Ua ib qho khoom siv ntau yam, ua haujlwm siab, stabilizer thiab zaj duab xis-tsim tus neeg sawv cev, HEC tau siv dav hauv kev lag luam coatings. Nws cov khoom zoo heev rheological, biocompatibility zoo thiab cov khoom siv tshuaj ruaj khov ua rau nws yog ib qho tseem ceeb hauv cov qauv txheej txheem niaj hnub.

1. Cov khoom tseem ceeb ntawm HEC

HEC muaj cov dej solubility zoo thiab tuaj yeem yaj sai sai hauv dej txias lossis dej kub kom tsim cov kua colloidal pob tshab thiab ruaj khov. Nws cov viscosity ntawm cov kua raug cuam tshuam los ntawm cov yam xws li cov concentration ntawm cov kua, kub, thiab shear rate, thiab qhia txog cov cwj pwm pseudoplastic ntws (piv txwv li, shear thinning yam ntxwv). Tsis tas li ntawd, HEC muaj kev ruaj khov zoo hauv ntau pH (2-12), muaj kev kam rau electrolytes zoo, thiab tsis yooj yim puas tsuaj los ntawm cov kab mob me me (cov tshuaj preservatives feem ntau ntxiv los txhim kho kev ruaj khov ntawm kev khaws cia).

Cov txiaj ntsig zoo tshaj plaws ntawm HEC suav nrog:

Cov nyhuv ua kom tuab: Ua kom cov viscosity ntawm lub txheej txheej thiab txhim kho kev ua haujlwm ntawm cov txheej.

Kev tswj hwm rheological: ua kom zoo dua qhov sag thiab leveling zog ntawm lub txheej.

Kev khaws dej: tiv thaiv dej kom tsis txhob evaporate sai dhau thaum lub sijhawm tsim kho thiab txhim kho cov yeeb yaj kiab zoo.

Kev Ruaj Ntseg: tswj kev ruaj ntseg ntawm cov mis nyob rau hauv ntau yam xwm txheej ib puag ncig.

Kev tawg ua kom sib kis tau: pab cov xim thiab cov khoom sau kom tawg ua kom sib npaug thiab tiv thaiv kom tsis txhob muaj nag thiab flocculation.

2. Daim ntawv thov ntawm hydroxyethyl cellulose hauv kev lag luam txheej

Hauv kev lag luam txheej, tshwj xeeb tshaj yog nyob rau hauv thaj chaw ntawm cov dej-raws li coatings, HEC yog dav siv, feem ntau nyob rau hauv cov hauv qab no:

(1) Ua ib qho thickener

HEC tuaj yeem ua rau kom cov dej-raws li txheej txheej viscosity nce ntxiv thiab muab cov txheej thixotropy zoo. Qhov ntau ntawm HEC tsim nyog tuaj yeem tiv thaiv cov txheej kom tsis txhob poob thaum txhuam, txheej txheej roller lossis txau, thiab pab txhim kho qhov puv thiab sib xws ntawm cov zaj duab xis txheej. Tsis tas li ntawd, cov khoom shear-thinning ntawm HEC txhim kho qhov fluidity ntawm cov txheej thaum siv lub zog sab nraud (xws li txhuam, txau), thiab qhov viscosity rov qab los thaum nws nyob ruaj khov kom tiv thaiv kev poob.

(2) Kev hloov kho cov cuab yeej rheological

Rheology yog ib qho ntawm cov cim qhia tseem ceeb ntawm kev ua tau zoo ntawm cov txheej txheem dej. HEC kho qhov kev ntxhov siab thiab cov kab ntws ntawm cov txheej txheem kom ua tiav qhov ntws zoo tshaj plaws thiab cov yam ntxwv kis tau zoo tshaj plaws hauv qab ntau txoj kev tsim kho. Tshwj xeeb tshaj yog nyob rau hauv cov ntsiab lus siab thiab cov qauv siab viscosity, HEC tuaj yeem muab kev xav zoo heev thiab kev sib npaug, txhim kho kev ua haujlwm ntawm kev tsim kho thiab qhov zoo ntawm cov txheej txheem.

(3) Lub luag haujlwm ntawm Stabilizer thiab dispersant

Hauv cov txheej txheem txheej, qhov kev sib cais ruaj khov ntawm cov xim thiab cov khoom sau yog qhov tseem ceeb rau kev ruaj khov cia thiab zoo ntawm cov txheej. HEC tuaj yeem tsim ib txheej tiv thaiv rau ntawm qhov chaw ntawm cov khoom me me kom tiv thaiv kev sib sau ua ke thiab kev tso dej ntawm cov khoom me me. Tib lub sijhawm, los ntawm kev nce qhov viscosity ntawm lub kaw lus, nws ua rau qeeb qeeb ntawm cov khoom me me, yog li txhim kho kev ruaj khov cia thiab xim sib xws ntawm cov txheej.

(4) Kev txhim kho cov dej tuav thiab cov khoom ua zaj duab xis

HEC muaj peev xwm khaws dej tau zoo heev. Nws tuaj yeem tiv thaiv kom tsis txhob muaj dej evaporation sai thaum lub sijhawm tsim kho, uas yog qhov zoo rau kev sib kis ntawm cov xim, kev sib txuas ua yeeb yaj kiab thiab kev txhim kho kev ua haujlwm ntawm cov txheej txheem kawg. Tshwj xeeb tshaj yog thaum siv rau ntawm qhov kub siab, qhuav lossis cov khoom siv uas muaj qhov dej, HEC tuaj yeem txhim kho qhov zoo li thiab du ntawm cov txheej txheem.

3. Cov yam tseem ceeb uas cuam tshuam rau kev ua tau zoo ntawm HEC

Hauv cov ntawv thov tshwj xeeb, kev ua tau zoo ntawm HEC raug cuam tshuam los ntawm cov hauv qab no:

Qib ntawm kev hloov pauv (DS) thiab kev hloov pauv molar (MS): DS sawv cev rau tus lej ntawm cov pab pawg hydroxyl hloov pauv ntawm txhua chav glucose, thiab MS sawv cev rau tus lej nruab nrab ntawm cov pab pawg hydroxyethyl uas tau qhia rau ib chav glucose. Feem ntau, tus nqi DS siab dua, qhov zoo dua qhov solubility ntawm HEC; tus nqi MS siab dua, qhov zoo dua qhov kev tiv thaiv ntsev thiab kev tiv thaiv kub.

Qhov hnyav molecular: Qhov hnyav molecular siab dua, qhov muaj zog ntawm cov nyhuv thickening ntawm HEC, tab sis lub sijhawm yaj kuj tseem ntev. Cov xwm txheej thov sib txawv (xws li cov txheej txheem phab ntsa, cov txheej txheem kev lag luam) muaj cov kev cai sib txawv rau qhov hnyav molecular.

Kev kho qhov chaw: Yuav kom txhim kho qhov kev sib kis ntawm HEC hauv dej txias, qee cov khoom HEC raug kho qhov chaw kom lawv tuaj yeem yaj sai sai hauv dej txias thiab txo qhov tshwm sim agglomeration tsim thaum lub sijhawm yaj.

4. Cov piv txwv ntawm daim ntawv thov

Hauv cov txheej txheem vaj tse xws li xim pleev xim rau sab hauv phab ntsa thiab xim pleev xim rau sab nraud phab ntsa, HEC yog siv los ua tus neeg sawv cev tseem ceeb rau kev ua kom tuab thiab rheology, uas tsis yog tsuas yog txhim kho qhov du ntawm kev tsim kho xwb, tab sis kuj ua rau cov nyhuv tiv thaiv kev sagging thiab kho kom zoo nkauj ntawm cov txheej txheem. Hauv cov teb ntawm cov txheej txheem kev lag luam, cov txheej txheem ntoo, cov ntawv luam ntawv, thiab lwm yam, HEC kuj siv dav vim nws qhov ruaj khov zoo thiab sib xws.

Hydroxyethyl cellulose tau dhau los ua tus neeg sawv cev tseem ceeb thiab tseem ceeb hauv kev tsim cov txheej txheem dej vim nws cov khoom zoo heev xws li thickening, rheology tswj, dej khaws cia thiab dispersion stability. Nrog rau kev cai lij choj ib puag ncig nruj dua thiab kev thov nce ntxiv rau cov txheej txheem dej, daim ntawv thov kev cia siab ntawmHEC hauv kev lag luam coatingsyuav dav dua. Yav tom ntej, kev tsim cov khoom HEC nrog kev yaj zoo dua, kev tiv thaiv huab cua zoo dua thiab kev ua haujlwm zoo dua yuav dhau los ua ib qho ntawm cov kev taw qhia tseem ceeb ntawm kev tsim kho tshiab hauv kev lag luam coatings.