1 Taw qhia
Tam sim no, cov khoom siv tseem ceeb siv hauv kev npaj ntawmCellulose etheryog paj rwb, thiab nws cov zis tau ploj zuj zus, thiab tus nqi tseem nce;
Ntxiv mus, feem ntau yog siv awswsifosed cov neeg sawv cev xws li chloroacetic acid (muaj kev lom zem) thiab ethylene oxide (carcinogenic) kuj muaj kev ua phem rau tib neeg lub cev thiab ib puag ncig. Phau ntawv
Nyob rau hauv tshooj no, cov pine cellulose nrog cov txheeb ze ntau dua 90% muab rho tawm hauv tshooj ob yog siv los ua cov khoom siv raw, thiab sodium chloroacetate thiab 2-chloroethanol yog siv los hloov chaw.
Siv cov tshuaj lom neeg lom zem heev acloroacetic acid raws li etherming tus neeg sawv cev, anionicCarboxymethyl cellulose (cmc), tsis-ionic hydrotethyl cellulose tau npaj.
Cellulose (HEC) thiab sib xyaw hydroxyethyl Carboxymethyl cellulose (HECMC) peb cov kws kho mob cellulose. ib qho
Cov txheej txheem npaj ntawm peb cov neeg ua tau zoo ntawm cellulose tau zoo los ntawm kev sim thiab ortthesized cov kev pab uas muaj kev hais ua ke, thiab synthesized cellulose kev siv tau raug tus cwj pwm los ntawm FT-IR, XRD, H-NMR, thiab lwm yam.
Cov qauv ntawm cov cellulose etherification
Lub hauv paus ntsiab lus ntawm cellulose etherification tuaj yeem faib ua ob ntu. Thawj ntu yog cov txheej txheem alkalization, uas yog, thaum lub sijhawm kev tawm tsam ntawm cellulose,
Tusyees dispersed nyob rau hauv Naoh daws, pine cellulose o o ua txhaum nyob rau hauv qhov kev txiav txim ntawm kev siv tshuab stirring, thiab nrog kev nthuav dav ntawm dej
Ib qho nyiaj ntau ntawm Naoh Molecules me me nkag mus rau sab hauv ntawm cov pab pawg ntawm cov ntoo thuv, thiab siv cov pab pawg hydroxyl ntawm lub nplhaib cov teeb meem zoo,
Tsim kom muaj alkali cellulose, lub chaw ua haujlwm ntawm lub here cov tshuaj tiv thaiv.
Qhov thib ob yog lub EriceCov txheej txheem, uas yog, cov tshuaj tiv thaiv ntawm cov chaw nquag thiab cov dej qab zib chloroacetate lossis 2-chloroethanol nyob rau hauv Alkaline tej yam kev mob, ua rau muaj
Nyob rau tib lub sijhawm, tus neeg sawv cev ntawm cov neeg sawv cev Sodium sodium c chloroocetate thiab 2-chloroethanol tseem yuav tsim muaj qee yam dej tsis huv.
Cov kev tshwm sim sab tau raug daws los tsim cov sodium glycolate thiab ethelene glycol, feem.
2 Lub siab Alkali Decrystallization Pretreatment ntawm Pine Cellulose
Ua ntej, npaj ib qho kev xav ntawm naoh daws nrog dej de deionized. Tom qab ntawd, ntawm qhov kub thiab txias, 2G ntawm cov ntoo thuv
Cov vitamin yog yaj nyob rau hauv qee qhov ntim ntawm Naoh daws, nplawm rau ib lub sijhawm, thiab tom qab lim rau kev siv.
Ntsuas Cov Qauv Chaw Tsim Tshuaj
Precececion PAUB Meter
COLLECTOR HOM XEEM CUA KUB Cua Kub Sib Nqus Stirrer
Lub tshuab nqus tsev qhuav cub
Hauv Seem
Circulating Dej Ntaus Ntau Lub Tshuab nqus tsev twj tso kua mis
Fourier Transform Infrated Spectrometer
X-tshav teb diffractometer
Nuclear Sib Nqus Revelonance Spectrometer
Hangzhou Aolilong Introlong Instrumental Co., Ltd.
Hangzhou Huichuaran Chaw Ua Vaj Tse Co., Ltd.
Shanghai Jinghong sim ua Co., Ltd.
Mettler toledo twj (Shanghai) Co., Ltd.
Hangzhou David Science thiab Kev Kawm Txuj Ci Co.
Miskas Miskas Fisher Co., Ltd.
Miskas Miskas Thermoelectric Switzerland Arl Company
Tuam Txhab Swuker Swuker
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Kev npaj ntawm CMCs
Kev Siv Ntoo thuv ntoo alkali cellulose pretreated los ntawm concentrated alkali decrystallization raws li cov khoom siv raw, siv ethanol li hnyav thiab siv sodium chloroacetate li etherification
CMC nrog cov DS ntau dua tau npaj los ntawm kev ntxiv cov alkali ob zaug thiab lub hnub nyoog ob zaug. Ntxiv 2G ntawm ntoo thuv ntoo alkali cellulose rau hauv plaub-caj dab wleask, tom qab ntawd ntxiv ib qho ntim ntawm ethanol cov kuab tshuaj, thiab do zoo rau 30min
hais txog, yog li ntawd cov alkali cellulose yog tag nrho dispersed. Tom qab ntawd ntxiv ib qho nyiaj ntawm Alkali tus neeg sawv cev thiab sodium chloroacetate kom muaj kev xav rau lub sijhawm ntawm ib lub sijhawm ntawm kev kub ntxhov herherification
Tom qab lub sijhawm, ib ob zaug ntxiv ntawm alkaline tus neeg sawv cev thiab sodium chloroacetate ua raws li los ntawm etherification rau ib lub sijhawm. Tom qab cov tshuaj tiv thaiv dhau lawm, txias thiab txias cia, ces
Neutralize nrog tus nqi tsim nyog ntawm glacial acetic acid, ces lim, ntxuav, ntxuav thiab qhuav.
Kev npaj ntawm Hecs
Siv thine ntoo alkali cellulose pretriceated alkali decrystallization raws li cov khoom siv raw, ethanol li hnyav thiab 2-chloroethanol li etherification
HEC nrog siab dua MS tau npaj los ntawm kev ntxiv alkali ob zaug thiab lub hnub nyoog rau tus neeg sawv cev ob zaug. Ntxiv 2G ntawm ntoo thuv ntoo alkali cellulose rau plaub-caj dab flask, thiab ntxiv ib qho ntim ntawm 90% (ntim feem) ethanol, do
Do rau ib lub sijhawm rau tag nrho cov disperse, tom qab ntawd ntxiv ib qho nyiaj ntawm alkali, thiab maj mam ua kom sov, ntxiv qee qhov ntim ntawm 2-
Chloroethanol, etherified at constant temperature for a period of time, and then added the remaining sodium hydroxide and 2-chloroethanol to continue etherification for a period of time. khoom qab zib
Tom qab cov tshuaj tiv thaiv tiav, neutralize nrog qee qhov nyiaj ntawm glacial acetic acid, thiab thaum kawg lim nrog lub khob lim (G3), ntxuav, thiab qhuav.
Kev npaj ntawm Hemcc
Siv cov hec npaj rau hauv 3.2.3.4 Raws li cov khoom siv raw, ethanol yog cov tshuaj tiv thaiv nruab nrab, thiab sodium chloroacetate raws li tus neeg sawv cev ntawm lub hnub nyoog los npaj
Hecmc. Cov txheej txheem tshwj xeeb yog: Siv qee qhov nyiaj ntawm HEC, muab tso rau hauv 100 ml plaub-caj dab raj, thiab tom qab ntawd ntxiv ib qho nqi ntawm ntim
90% ethanol, mechanically do rau ib lub sijhawm kom nws tag nrho cov dispersed, ntxiv ib qho nyiaj ntawm alkali tom qab cua sov, thiab maj mam ntxiv
Sodium chloroacetate, lub etherification ntawm nruab nrab kub xaus tom qab lub sijhawm. Tom qab cov tshuaj tiv thaiv tiav, neutralize nws nrog glacial acetic acid rau neutralize nws, ces siv iav lim (G3)
Tom qab nqus tau kom pom, ntxuav thiab kom qhuav.
Ua kom huv huv ntawm cellulose neeg muaj kev pab
Nyob rau hauv cov txheej txheem npaj ntawm cellulose ether, qee cov khoom lag luam feem ntau tsim, feem ntau yog inorganic ntsev sodium chloride thiab lwm yam
impurities. Txhawm rau txhim kho qhov zoo ntawm cellulose ether, kev ua kom zoo, yooj yim purification tau nqa tawm ntawm cov cellulose ether. Vim tias lawv nyob hauv dej
Muaj ntau solubility, yog li kev sim siv qee cov ntim cov khoom ntim ntawm ethanol kom huv si npaj peb cov kws kho cellulose.
Hloov.
Tso lub cellulose ether cov qauv npaj nrog rau 60% ℃ ~ 65 ℃ / ℃ ℃ eth 6 6 ℃ ℃ ℃ const temperature Cua kub Stirrigricet Rau 10 ℃. min. Coj supernatant kom qhuav
Nyob rau hauv ib tug beaker huv, siv nyiaj nitrate los xyuas rau chloride ions. Yog hais tias muaj ib tug dawb precipally, lim nws los ntawm ib lub khob lim thiab coj khoom
Rov ua cov kauj ruam dhau los rau lub cev ntawm lub cev, kom txog thaum cov filtrate tom qab ntxiv 1 dolt of Agpe3 daws tsis muaj nag lossis ntxuav, ua kom huv.
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rau hauv (feem ntau kom tshem tawm cov tshuaj tiv thaiv los ntawm cov khoom nacl). Tom qab kev nqus pom lim, ziab, cua txias mus rau chav sov thiab qhov hnyav.
Loj, g.
Kev xeem thiab cov qauv ntawm cov qauv rau cellulose muaj kev hais ua
Kev txiav txim siab ntawm Qib Kev Hloov (DS) thiab MOROLED CRIVA LOS (MS)
Kev txiav txim siab ntawm DS: Ua ntej, hnyav 0.2 g (raug rau 0.1 mg) ntawm kev huv thiab cov qauv qhuav ether ether ether, yaj nws hauv
80ml ntawm cov dej distilled, do hauv qhov dej tsis tu ncua da dej ntawm 30 ℃ ~ 40 ℃ rau 10min. Tom qab ntawd kho nrog sulfuric acid daws los yog naoh daws
Ph ntawm kev daws kom txog thaum lub Ph ntawm Txoj Kev daws yog 8. Tom qab ntawd nyob rau hauv ib tug beaker nruab nrog pot me me ntawm sulfuric acid
Rau lub siab, nyob rau hauv cov kev mob txhaws, soj ntsuam lub ntsuas hluav taws xob nyeem thaum lub sij hawm pH nqi ntawm kev daws teeb meem tau hloov kho rau 3.74,
Lub kaum no xaus. Nco ntsoov cov ntim ntawm cov sulfuric acid txheem siv nyob rau lub sijhawm no.
Tiam:
Qhov suav ntawm cov lej proton sauv thiab cov pab pawg hydroxyethyl
Qhov sib piv ntawm cov lej ntawm cov protons sab saud; I7 yog qhov loj ntawm cov pab pawg methylene ntawm cov pab pawg hydroxyethyl
Kev siv ntawm cov proton resonance remononance ncov; yog cov kev siv ntawm cov proton resonance peak ntawm 5 methine pab pawg thiab ib methylene pawg ntawm cov cellulose chav nyob
Suav.
Txoj kev xeem tau piav qhia txog qhov kev sim ua cim infrared ntawm peb lub cellulose pab neeg ua haujlwm cmc, HEC thiab Heecmc
Txoj kev cai
3.2.4.3 XRD Test
Xoo hluav taws xob kev soj ntsuam cov xeeb ceem ntawm peb lub cellulose pab pawg cmc, HEC thiab Heecmc
Txoj kev xeem piav qhia.
3.2.4.4 Kev sim H-NMR
Lub H NMR Spectrometer ntawm HEC tau ntsuas los ntawm Avance400 h NMR Spectrometer ua rau los ntawm Bruker.
Siv deuterated Duethyl sulethyl sulfoxide li kuab tshuaj, kev daws tau raug sim los ntawm kua hydrogen nmr spectroscopy. Qhov ntsuas zaus yog 75.5.5MHz.
Sov, kev daws teeb meem yog 0.5ml.
3.3 Cov ntsiab lus thiab kev tshuaj xyuas
3.3.1 Optimization ntawm CMC npaj cov txheej txheem
Siv cov pine cellulose muab rho tawm hauv tshooj ob yog cov khoom siv raw, thiab siv sodium chloroacetate ua tus sawv cev ntawm tus neeg sawv cev, tus qauv ntawm ib leeg tau sim tau txais,
Cov txheej txheem npaj ntawm CMC tau ua kom zoo, thiab thawj cov nyom ntawm kev sim tau teeb tsa raws li qhia hauv Table 3.3. Cov hauv qab no yog tus txheej txheem npaj hec
Hauv kev kos duab, kev tsom xam ntawm ntau yam.
Rooj 3.3 Pib Faction Qhov Tseem Ceeb
Factor Pib Tus Nqi
Pretreatment alkalizing kub / ℃ 40
Pretreatment alkalizing sij hawm / h 1
Pretrasticment tau-kua piv / (G / ML) 1:25
Pretricatment lye concentration /% 40
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Thawj theem itherification kub / ℃ 45
Thawj-theem aterification lub sij hawm / h 1
Qeb ob itherification kub / ℃ 70
Theem Nrab Thib Ob Lub Sij Hawm Lub Sij Hawm / H 1
POOB DOSAGE hauv theem etheriification / g 2
Tus nqi ntawm lub hnub nyoog uas sawv cev hauv etherification theem / g 4.3
Etheried cov kua-kua piv / (G / ml) 1:15
3.3.1.1 Cawv ntawm ntau yam ntawm CMC hloov pauv hauv Pretreatment Alkalization theem
1. Cov nyhuv ntawm pretreatment alkalization kub txog ntawm kev hloov pauv ntawm CMC
Txhawm rau xav txog cov nyhuv ntawm pretreatment alkalization kub txog ntawm cov neeg kawm ntawv hloov chaw nyob rau hauv cov kis tau CMC, nyob rau hauv cov ntaub ntawv ntawm kev txhim kho lwm yam uas tseem ceeb,
Nyob rau hauv cov xwm txheej, cov nyhuv ntawm pretreatment alkalization kub ntawm cmc hloov qib degree tau tham txog, thiab cov txiaj ntsig tau qhia hauv Daim Duab.
Pretreatment alkalizing kub / ℃
Cov nyhuv ntawm pretreaticatment alkalizing kub ntawm cmc hloov
Nws tuaj yeem pom tias cov qib ntawm CMC nce nrog kev nce ntawm pretreaticating alkalization kub, thiab lub alkalization kub yog 30 ° C.
Cov theem saum toj no ntawm kev hloov chaw txo qis nrog kev nce kub. Qhov no yog vim hais tias lub alkalizing kub yog tsawg dhau, thiab cov lwg me me yog qhov tsis muaj peev xwm ua tau thiab tsis tuaj yeem ua
Ua tau zoo ua kom lub ntsej muag crystalline ntawm cellulose, uas ua rau nws nyuaj rau lub cellulose kom nkag mus rau sab hauv ntawm lub Tsibkulose theem, thiab theem ntawm cov tshuaj tiv thaiv kuj muaj siab.
Tsawg, ua rau muaj qis dua ntawm cov khoom lag luam. Txawm li cas los xij, cov alkalization kub yuav tsum tsis txhob siab dhau. Raws li qhov kub nce ntxiv, nyob rau hauv kev txiav txim ntawm cov kub thiab muaj zog alkali,
Cellulose yog nquag mus rau oxidative tsis, thiab qib hloov chaw ntawm cov khoom muag CMC txo.
2. Dab neeg ntawm pretreatment alkalinization lub sij hawm ntawm cmc hloov kev kawm
Raws li cov xwm txheej uas ua ntej kev sib tw kub yog 30 ° C thiab lwm yam yog thawj zaug tshwm sim ntawm CMC tau sib tham.
Cov nyhuv ntawm kev hloov chaw. Qib ntawm kev hloov pauv
Pretreatment alkalizing sij hawm / h
Cov nyhuv ntawm pretreatment alkalinization lub sij hawm ntawmCmcTshuav
Cov txheej txheem loj nws tus kheej yog qhov nrawm dua, tab sis alkali daws tau xav tau ib qho diffusion sij hawm hauv cov fiber.
Nws tuaj yeem pom tau tias thaum lub sijhawm alkalization yog 0.5-1.5h, kev hloov pauv ntawm cov khoom nce nrog kev nce ntawm lub sijhawm sib dhos.
Cov degree ntawm cov khoom tau tau yog qhov siab tshaj plaws thaum lub sijhawm yog 1.5H, thiab qib hloov pauv tau txo qis ntawm lub sijhawm tom qab 1.5H. Qhov no tuaj yeem ua tau
Tej zaum nws yuav yog vim thaum pib ntawm kev sib kis, nrog lub sijhawm ua ntej ntawm alkali mus rau cellulose tau txaus, yog li ntawd cov fiber ntau
Tus qauv Prime yog so ntau dua, nce qhov chaw sawv cev ceg ntoo thiab cov nquag nruab nrab
Lub sijhawm Post: Plaub-26-2024