Focus on Cellulose ethers

Dab tsi yog cov khoom ntawm methylcellulose?

1. Nws tuaj yeem yaj tau thaum kub siab tshaj 200 ° C, thiab cov hmoov tshauv yog li 0.5% thaum hlawv, thiab nws yog nruab nrab tom qab ua rau hauv slurry nrog dej. Raws li rau nws cov viscosity, nws nyob ntawm nws qib ntawm polymerization.

2. Solubility nyob rau hauv dej yog inversely proportional rau kub, siab kub muaj tsawg solubility, tsis tshua muaj kub muaj siab solubility.

3. Soluble nyob rau hauv cov sib tov ntawm dej thiab organic solvents xws li methanol, ethanol, ethylene glycol, glycerin thiab acetone.

4. Thaum cov hlau ntsev los yog cov organic electrolyte muaj nyob rau hauv nws cov kua aqueous, cov tshuaj tseem tuaj yeem nyob ruaj khov. Thaum cov electrolyte ntxiv rau hauv ib qho loj, gel lossis nag lossis daus yuav tshwm sim.

5. Kev ua haujlwm saum npoo av. Nws cov molecules muaj pawg hydrophilic thiab hydrophobic pawg, uas muaj emulsification, colloid tiv thaiv thiab theem stability.

6. Thermal gelation. Thaum cov tshuaj aqueous nce mus rau qhov kub thiab txias (saum lub gel kub), nws yuav ua huab kom txog thaum nws gels los yog precipitates, ua rau cov tshuaj poob nws cov viscosity, tab sis nws tuaj yeem rov qab mus rau nws qhov qub qub los ntawm kev txias. Qhov kub ntawm qhov gelation thiab nag lossis daus tshwm sim nyob ntawm hom khoom, qhov concentration ntawm cov tshuaj thiab tus nqi cua sov.

7. Tus nqi pH ruaj khov. Lub viscosity hauv dej tsis yooj yim cuam tshuam los ntawm acid thiab alkali. Tom qab ntxiv ib qho nyiaj ntawm alkali, tsis hais qhov kub thiab txias, nws yuav tsis ua rau decomposition lossis saw splitting.

8. Cov tshuaj tuaj yeem tsim cov pob tshab, tawv thiab elastic zaj duab xis ntawm qhov chaw tom qab ziab. Nws tuaj yeem tiv taus cov kuab tshuaj organic, roj thiab ntau yam roj. Nws yuav tsis tig daj thaum raug lub teeb, thiab yuav tsis tshwm cov kab nrib pleb. Nws tuaj yeem yaj hauv dej dua. Yog tias formaldehyde ntxiv rau cov tshuaj lossis tom qab kho nrog formaldehyde, zaj duab xis yog insoluble hauv dej tab sis tseem qee qhov o.

9. Thickening. Nws tuaj yeem ua kom dej thiab cov tshuab tsis muaj dej, thiab muaj kev ua haujlwm zoo los tiv thaiv sag.

10. nce viscosity. Nws cov kua dej aqueous muaj zog cohesive, uas tuaj yeem txhim kho lub zog sib txuam ntawm cov cement, gypsum, xim, xim, wallpaper thiab lwm yam ntaub ntawv.

11. Cov teeb meem raug ncua. Nws tuaj yeem siv los tswj cov coagulation thiab nag lossis daus ntawm cov khoom siv.

12. Kev tiv thaiv colloid kom nws ruaj khov. Nws tuaj yeem tiv thaiv kev sib sau ua ke thiab coagulation ntawm cov tee dej thiab cov pigments, thiab tiv thaiv tau los nag.


Post lub sij hawm: Jan-29-2023
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