Dab tsi yog cov khoom ntawm carboxymethyl cellulose?

Dab tsi yog cov khoom ntawm carboxymethyl cellulose?

Teb:Carboxymethyl cellulosekuj muaj cov khoom sib txawv vim nws qhov sib txawv ntawm kev hloov pauv. Qib ntawm kev hloov pauv, tseem hu ua degree ntawm etherification, txhais tau hais tias qhov nruab nrab ntawm H hauv peb OH hydroxyl pawg hloov los ntawm CH2COONa. Thaum peb pawg hydroxyl ntawm lub nplhaib cellulose muaj 0.4 H hauv pawg hydroxyl hloov los ntawm carboxymethyl, nws tuaj yeem yaj hauv dej. Lub sijhawm no, nws yog hu ua 0.4 hloov pauv qib lossis nruab nrab hloov pauv qib (hloov qib 0.4-1.2).

Cov khoom ntawm carboxymethyl cellulose:

(1) Nws yog hmoov dawb (los yog coarse grain, fibrous), tasteless, harmless, yooj yim soluble nyob rau hauv dej, thiab tsim ib tug pob tshab nplaum, thiab cov tshuaj yog nruab nrab los yog me ntsis alkaline. Nws muaj zoo dispersion thiab khi zog.

(2) Nws cov tshuaj aqueous tuaj yeem siv los ua emulsifier ntawm roj / dej hom thiab dej / roj hom. Nws kuj muaj peev xwm emulsifying rau roj thiab siv quav ciab, thiab yog ib qho muaj zog emulsifier.

(3) Thaum cov tshuaj ntsib cov ntsev hnyav hlau xws li lead acetate, ferric chloride, silver nitrate, stannous chloride, thiab potassium dichromate, nag lossis daus tuaj yeem tshwm sim. Txawm li cas los xij, tshwj tsis yog cov hmoov lead acetate, nws tseem tuaj yeem rov ua dua hauv cov tshuaj sodium hydroxide, thiab cov precipitates xws li barium, hlau thiab txhuas yog yooj yim soluble hauv 1% ammonium hydroxide tov.

(4) Thaum cov tshuaj ntsib cov organic acid thiab inorganic acid tov, nag lossis daus tuaj yeem tshwm sim. Raws li kev soj ntsuam, thaum pH tus nqi yog 2.5, turbidity thiab nag lossis daus tau pib. Yog li pH 2.5 tuaj yeem suav tias yog qhov tseem ceeb.

(5) Rau cov ntsev xws li calcium, magnesium thiab lub rooj ntsev, tsis muaj nag lossis daus yuav tshwm sim, tab sis cov viscosity yuav tsum tau txo, xws li ntxiv EDTA lossis phosphate thiab lwm yam tshuaj tiv thaiv.

(6) Qhov kub thiab txias muaj qhov cuam tshuam zoo rau viscosity ntawm nws cov kua dej aqueous. Lub viscosity txo qis sib xws thaum kub nce, thiab rov ua dua. Kev ruaj ntseg ntawm cov viscosity ntawm cov kua dej ntawm chav tsev kub tseem tsis hloov pauv, tab sis cov viscosity tuaj yeem maj mam txo thaum rhuab saum 80 ° C rau lub sijhawm ntev. Feem ntau, thaum qhov kub tsis tshaj 110 ° C, txawm tias qhov kub thiab txias tau khaws cia rau 3 teev, thiab tom qab ntawd txias mus rau 25 ° C, qhov viscosity tseem rov qab los rau nws qhov qub; Tab sis thaum qhov kub thiab txias yog rhuab mus rau 120 ° C rau 2 teev, txawm hais tias qhov kub thiab txias tau rov qab los, viscosity poob los ntawm 18.9%. .

(7) Tus nqi pH kuj tseem yuav muaj qee yam cuam tshuam rau viscosity ntawm nws cov kua dej aqueous. Feem ntau, thaum pH ntawm cov tshuaj uas tsis muaj viscosity sib txawv ntawm qhov nruab nrab, nws cov viscosity muaj qhov cuam tshuam me ntsis, thaum lub nruab nrab-viscosity tov, yog tias nws cov pH sib txawv ntawm qhov nruab nrab, viscosity pib maj mam txo; Yog hais tias pH ntawm high-viscosity tov deviates los ntawm nruab nrab, nws viscosity yuav txo. Kev poob qis.

(8) Tau tshaj lwm cov dej-soluble kua nplaum, softeners thiab resins. Piv txwv li, nws yog sib xws nrog tsiaj kua nplaum, cov pos hniav arabic, glycerin thiab soluble starch. Nws kuj yog sib xws nrog cov iav dej, polyvinyl cawv, urea-formaldehyde resin, melamine-formaldehyde resin, thiab lwm yam, tab sis kom tsawg dua.

(9) Cov yeeb yaj kiab ua los ntawm irradiating ultraviolet lub teeb rau 100 teev tseem tsis muaj xim los yog brittleness.

(10) Muaj peb qhov viscosity ntau yam xaiv los ntawm raws li daim ntawv thov. Rau gypsum, siv cov viscosity nruab nrab (2% aqueous tov ntawm 300-600mPa·s), yog tias koj xaiv viscosity siab (1% tov ntawm 2000mPa·s lossis ntau dua), koj tuaj yeem siv nws hauv qhov ntau npaum li cas yuav tsum tau txo qis kom tsim nyog.

(11) Nws cov kua dej aqueous ua raws li kev tiv thaiv hauv gypsum.

(12) Cov kab mob thiab cov kab mob tsis muaj qhov pom tseeb ntawm nws daim ntawv hmoov, tab sis lawv muaj kev cuam tshuam rau nws cov tshuaj aqueous. Tom qab kis kab mob, viscosity yuav poob thiab mildew yuav tshwm sim. Ntxiv qhov tsim nyog ntawm cov tshuaj tua kab mob ua ntej tuaj yeem tswj nws cov viscosity thiab tiv thaiv mildew rau lub sijhawm ntev. Muaj cov tshuaj preservatives yog: BIT (1.2-benzisothiazolin-3-one), racebendazim, thiram, chlorothalonil, thiab lwm yam. Cov nyiaj siv ntxiv hauv cov tshuaj aqueous yog 0.05% rau 0.1%.

Hydroxypropyl methylcellulose zoo npaum li cas ua tus neeg saib xyuas dej rau anhydrite binder?

Teb: Hydroxypropyl methylcellulose yog cov dej ua haujlwm zoo rau cov ntaub ntawv gypsum cementitious. Nrog rau qhov nce ntawm cov ntsiab lus ntawm hydroxypropyl methylcellulose. Cov dej tuav ntawm gypsum cemented cov ntaub ntawv nce sai heev. Thaum tsis muaj dej tuav tus neeg sawv cev ntxiv, cov dej tuav tus nqi ntawm gypsum cemented khoom yog li 68%. Thaum cov dej tuav tus neeg sawv cev yog 0.15%, cov dej tuav tus nqi ntawm gypsum cemented khoom tuaj yeem ncav cuag 90.5%. Thiab cov dej tuav yuav tsum tau ntawm lub hauv qab plaster. Qhov ntau npaum ntawm cov dej tuav tus neeg sawv cev ntau dua 0.2%, ntxiv cov tshuaj ntxiv, thiab cov dej tuav tus nqi ntawm cov khoom gypsum cementitious nce qeeb. Kev npaj cov ntaub ntawv anhydrite plastering. Qhov tsim nyog npaum li cas ntawm hydroxypropyl methylcellulose yog 0.1% -0.15%.

Dab tsi yog qhov sib txawv ntawm cov cellulose sib txawv ntawm plaster ntawm paris?

Teb: Ob qho tib si carboxymethyl cellulose thiab methyl cellulose tuaj yeem siv los ua cov dej khaws cia rau plaster ntawm paris, tab sis cov dej tuav cov nyhuv ntawm carboxymethyl cellulose yog qis dua li ntawm methyl cellulose, thiab carboxymethyl cellulose muaj sodium ntsev, yog li nws tsim nyog rau Plaster ntawm Paris muaj lub zog retarding nyhuv thiab txo lub zog ntawm plaster.Methyl celluloseyog ib qho zoo tagnrho admixture rau gypsum cementitious cov ntaub ntawv integrating dej tuav, thickening, ntxiv dag zog rau, thiab viscosifying, tshwj tsis yog tias ib co ntau yam muaj ib tug retarding nyhuv thaum ntau npaum. siab tshaj carboxymethyl cellulose. Vim li no, feem ntau gypsum composite gelling cov ntaub ntawv tau txais cov txheej txheem ntawm kev sib xyaw carboxymethyl cellulose thiab methyl cellulose, uas tsis tsuas yog siv lawv cov yam ntxwv (xws li cov nyhuv retarding ntawm carboxymethyl cellulose, cov nyhuv txhawb zog ntawm methyl cellulose), thiab siv lawv cov txiaj ntsig zoo (xws li lawv cov dej tuav). Nyob rau hauv txoj kev no, ob qho tib si dej tuav kev ua tau zoo ntawm cov khoom siv gypsum cementitious thiab kev ua tau zoo ntawm cov khoom siv gypsum cementitious tuaj yeem txhim kho, thaum tus nqi nce yog khaws cia ntawm qhov qis tshaj.