1 Hordhac
Waqtigan xaadirka ah, alaabta ceeriin ee ugu weyn ee loo isticmaalo diyaarintaether cellulosewaa cudbi, wax-soo-saarkiisuna wuu sii yaraanayaa, qiimuhuna wuu sii kordhayaa;
Waxaa intaa dheer, walxaha sida caadiga ah loo isticmaalo etherifying sida chloroacetic acid (oo aad u sun ah) iyo ethylene oxide (kansarka) ayaa sidoo kale waxyeello u leh jidhka bini'aadamka iyo deegaanka. Buug
Cutubkan, cellulose geed leh oo nadiif ah oo ka badan 90% laga soo saaray cutubka labaad ayaa loo isticmaalaa sida alaabta ceeriin, iyo sodium chloroacetate iyo 2-chloroethanol ayaa loo isticmaalaa beddelka.
Isticmaalka chloroacetic acid ee sunta sare leh sida wakiilka etherifying, anionicCarboxymethyl cellulose (CMC), cellulose hydroxyethyl non-ionic ayaa la diyaariyey.
Cellulose (HEC) iyo hydroxyethyl karboxymethyl cellulose (HECMC) isku qasan saddex ethers cellulose. hal arrin
Farsamooyinka diyaarinta ee saddexda ethers cellulose ayaa lagu hagaajiyay iyada oo la adeegsanayo tijaabooyinka iyo tijaabooyinka orthogonal, iyo ether-ka unugyadu isku dhafan ayaa lagu gartaa FT-IR, XRD, H-NMR, iwm.
Aasaaska etherification cellulose
Mabda'a etherification cellulose waxaa loo qaybin karaa laba qaybood. Qaybta hore waa habka alkalization, taas oo ah, inta lagu guda jiro falcelinta alkalization ee cellulose,
Si siman ugu kala firirsan xalalka NaOH, cellulose geed baa si xoog leh u barara marka ay hoos timaado ficilka walaaqida farsamada, iyo ballaadhinta biyaha
Xaddi badan oo ah unugyo yaryar oo NaOH ah ayaa gudaha u galay cellulose geed, waxayna la falgaleen kooxaha hydroxyl ee giraanta unugga qaabdhismeedka gulukoosta,
Waxay abuurtaa alkali cellulose, xarunta firfircoon ee falcelinta etherification.
Qaybta labaad waa habka etherification, taas oo ah, falcelinta u dhaxaysa xarunta firfircoon iyo sodium chloroacetate ama 2-chloroethanol hoos xaaladaha alkaline, taasoo keentay in
Isla mar ahaantaana, wakiilka etherifying sodium chloroacetate iyo 2-chloroethanol ayaa sidoo kale soo saari doona heer biyo ah oo hoos yimaada xaaladaha alkaline.
Dareen-celinta dhinaca ayaa la xalliyaa si ay u abuuraan glycolate sodium iyo ethylene glycol, siday u kala horreeyaan.
2 Decrystallization alkali oo urursan pretreatment of cellulose geed
Marka hore, diyaari xaddi gaar ah oo xal NaOH ah oo leh biyo fuuq-baxay. Kadib, heerkul gaar ah, 2g oo fiber geed ah
Fitamiinka waxa lagu milmaa mug go'an oo ah xal NaOH ah, oo la walaaqay in muddo ah, ka dibna lagu sifeeyo isticmaalka.
Soo saaraha Model Qalabka
Mitirka pH ee saxda ah
Nooca ururiyaha heerkulka joogtada ah kululaynta birlab
Foornada qallajinta faakium
dheelitirka elegtarooniga ah
Wareegga nooca biyaha ee ujeedo badan leh
Fourier Transform Infrared Spectrometer
raajada diffractometer
Spectrometer Resonance Nuclear Magnetic Resonance Spectrometer
Hal qayb oo ka mid ah Hangzhou Aolilong Instrument Co., Ltd.
Hangzhou Huichuang Instrument Equipment Co., Ltd.
Shirkadda Shanghai Jinghong Experimental Equipment Co., Ltd.
METTLER TOLEDO Instruments (Shanghai) Co., Ltd.
Hangzhou David Science and Education Instrument Co., Ltd.
Hal qayb oo ka mid ah American Thermo Fisher Co., Ltd.
American Thermoelectric Switzerland ARL Company
Shirkadda Swiss-ka ah ee BRUKER
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Diyaarinta CMC-yada
Isticmaalka alwaax alwaax alwaax ah cellulose pretreated by alkali decrystallization xoogaysan sida walxo ceeriin, isticmaalaya ethanol sida dareere ah iyo isticmaalka sodium chloroacetate sida etherification.
CMC oo leh DS sare ayaa la diyaariyey iyadoo lagu daray alkali laba jeer iyo wakiilka etherifying laba jeer. Ku dar 2g oo alwaax alwaax alwaax ah weelka afarta luqun leh, ka dibna ku dar mug cayiman oo dareere ethanol ah, oo si fiican u walaaq 30min
ku saabsan, si cellulose alkali si buuxda u kala firdhiso. Ka dib ku dar qadar go'an oo ah wakiilka alkali iyo sodium chloroacetate si ay uga falceliso muddo wakhti heerkul go'an
Waqti ka dib, ku darida labaad ee wakiilka alkaline iyo sodium chloroacetate oo ay ku xigto etherification muddo wakhti ah. Ka dib markii falcelintu dhammaato, qabooji oo qabooji, ka dibna
Dhexdhexaad ka dhig qadar habboon oo ah glacial acetic acid, ka dibna shaandhaynta nuugista, dhaq oo qalaji.
Diyaarinta HECs
Isticmaalka alwaax alwaax alwaax ah oo lagu sii darey alkali decrystallization xoog leh sida walxo ceeriin ah, ethanol sida dareere ah iyo 2-chloroethanol sida etherification.
HEC ee leh MS sare waxaa la diyaariyey iyadoo lagu daray alkali laba jeer iyo wakiilka etherifying laba jeer. Ku dar 2g oo alwaax alwaax ah oo alwaax ah oo ku rid weel afar-lugood leh, oo ku dar mugga 90% (jajab mugga) ethanol, walaaq.
Walaaq in muddo ah si aad si buuxda u kala firdhiso, kadibna ku dar qadar alkali ah, si tartiib ah u kululee, ku dar mug cayiman 2-
Chloroethanol, oo lagu miiray heerkul joogto ah muddo wakhti ah, ka dibna lagu daray soodhiyam hydroxide ee soo hadhay iyo 2-chloroethanol si ay u sii wado etherification muddo wakhti ah. daweyn
Ka dib marka falcelinta la dhammeeyo, ku dami qadar go'an oo ah glacial acetic acid, oo ugu dambayntii ku sifee shaandhaynta dhalada ah (G3), dhaq oo qallaji.
Diyaarinta HEMCC
Isticmaalka HEC ee lagu diyaariyey 3.2.3.4 sida alaabta ceeriin, ethanol sida dhexdhexaadiyaha falcelinta, iyo sodium chloroacetate sida wakiilka etherifying si loogu diyaariyo
HECMC. Habka gaarka ah waa: Qaado qaddar go'an oo HEC ah, ku rid 100 ml oo ah faashad afar qoor ah, ka dibna ku dar qadar mugga ah.
90% ethanol, si farsamaysan u walaaq muddo wakhti ah si ay si buuxda u kala firdhiso, ku dar qadar go'an oo alkali ah kuleylka ka dib, oo si tartiib ah ugu dar
Sodium chloroacetate, etherification heerkulka joogtada ah wuxuu dhamaanayaa muddo ka dib. Ka dib marka falcelinta la dhammeeyo, ku dhex milmi glacial acetic acid si aad u dhexdhexaadiso, ka dibna isticmaal shaandhada dhalada ah (G3)
Sifeynta nuugista ka dib, dhaqida iyo qalajinta.
Nadiifinta ethers cellulose
Habka diyaarinta ee ether cellulose, qaar ka mid ah alaabooyinka ayaa inta badan la soo saaraa, inta badan cusbada chloride sodium inorganic iyo qaar kale.
wasakhda. Si loo hagaajiyo tayada ether-ka cellulose, nadiifinta fudud ayaa lagu sameeyay ether-ka cellulose ee la helay. sababtoo ah waxay ku jiraan biyaha
Waxaa jira kala duwanaansho kala duwan, sidaas darteed tijaabadu waxay isticmaashaa qayb mug leh oo ethanol ah si loo nadiifiyo saddexda ethers cellulose ee la diyaariyey.
isbedel.
Ku rid muunada ether-ka cellulose ee lagu diyaariyey tayada qaarkeed, ku dar qadar go'an oo ah 80% ethanol kaas oo horay loo sii kululeeyay ilaa 60 ℃ ~ 65 ℃, oo ilaali walaaqida farsamada 60 ℃ ~ 65 ℃ heerkulka joogtada ah ee kuleylka kuleylka loogu talagalay 10 ℃. min. Qaado subaga si aad u qalajiso
Gawaarida nadiifka ah, isticmaal nitrate silver si aad u hubiso ions chloride. Haddii uu jiro roob cad, ku sifee shaandhada dhalada oo qaado ta adag
Ku celi tillaabooyinka hore ee qaybta jidhka, ilaa shaandhaynta ka dib marka lagu daro 1 dhibcood oo AgNO3 ah ma laha wax cad oo cad, taas oo ah, nadiifinta iyo dhaqidda la dhammeeyo.
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galay (inta badan si meesha looga saaro falcelinta ka-soo-saarka NaCl). Sifeynta nuugista ka dib, qalajinta, qaboojinta heerkulka qolka iyo miisaanka.
tiro, g.
Tijaabada iyo Hababka Astaamaha ee Ethers Cellulose
Go'aaminta Darajada Beddelka (DS) iyo Degree Bedelka (MS)
Go'aaminta DS: Marka hore, miisaan 0.2 g (sax ah ilaa 0.1 mg) ee muunadda ether-ka ee la sifeeyey oo la qalajiyey, ku milmi
80mL oo biyo nadiif ah, walaaqay qubeyska heerkulka joogtada ah ee 30℃ ~ 40℃ 10min. Ka dibna ku hagaaji xal sulfuric acid ama xalalka NaOH
pH ee xalka ilaa pH ee xalku yahay 8. Kadibna weel ku qalabaysan mitirka pH, isticmaal xal caadi ah oo ah sulfuric acid
Si loo titrate, xaaladaha kicinta, u fiirso akhrinta mitirka pH inta aad titrating, marka qiimaha pH ee xalka lagu hagaajiyo 3.74,
Titrationku wuu dhamaanayaa. U fiirso mugga xalalka sulfuric acid ee la isticmaalay wakhtigan.
Jiilka:
Wadarta tirooyinka borotoonka sare iyo kooxda hydroxyethyl
Saamiga tirada borotoonnada sare; I7 waa tirada kooxda methylene ee kooxda hydroxyethyl
Xoojinta ugu sarreysa resonance proton; waa xoogga sare ee resonance proton ee 5 kooxaha methine iyo hal koox methylene oo ku taal unugga gulukooska cellulose
Isku soo wada duuboo
Hababka tijaabada ah ee lagu sharraxay tijaabinta astaamaha infrared ee saddexda ethers cellulose CMC, HEC iyo HEECMC
Sharciga
3.2.4.3 Imtixaanka XRD
Tijaabada Astaamaha Falanqaynta Kala-duwanaanta Raajada ee Saddexda Ethers Cellulose CMC, HEC iyo HEECMC
habka tijaabada lagu tilmaamay.
3.2.4.4 Tijaabada H-NMR
spectrometerka H NMR ee HEC waxa lagu qiyaasay Avance400 H NMR spectrometer oo ay soo saartay BRUKER.
Isticmaalka dimethyl sulfoxide deuterated sida dareere ahaan, xalka waxaa lagu tijaabiyay dareeraha hydrogen NMR spectroscopy. Inta jeer ee tijaabadu waxay ahayd 75.5MHz.
Diirimaad, xalku waa 0.5ml.
3.3 Natiijooyinka iyo Falanqaynta
3.3.1 Hagaajinta habka diyaarinta CMC
Isticmaalka cellulose-ka geedka ee laga soo saaro cutubka labaad sida alaabta ceeriin, iyo isticmaalka sodium chloroacetate sida wakiilka etherifying, habka tijaabada hal arrin ayaa la qaatay,
Habka diyaarinta ee CMC ayaa la hagaajiyay, iyo doorsoomayaasha bilowga ah ee tijaabada ayaa la dejiyay sida ku cad Shaxda 3.3. Kuwa soo socda waa habka diyaarinta HEC
Farshaxanka, falanqaynta arrimo kala duwan.
Shaxda 3.3 Qiimaha Hore ee Qodobbada
Qodobka ugu horreeya qiimaha
Heerkulka alkalizing ee ka-hortagga daaweynta/℃ 40
Wakhtiga alkalization ka-hortagga 1
Saamiga dareeraha adag ee ka-hortagga/(g/ml) 1:25
U-fiirsashada ka-hortagga lye/% 40
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Heerkulka heerkulbeegga heerka koowaad/℃ 45
Waqtiga etherification heerka koowaad/h 1
Heerkulka heerka labaad ee etherification/℃ 70
Wakhtiga etherification marxaladda labaad 1
Qiyaasta saldhigga ah ee heerka etherification/g 2
Qadarka wakiilka etherification ee marxaladda etherification/g 4.3
Saamiga dareeraha adag ee etherified/(g/ml) 1:15
3.3.1.1 Saamaynta arrimo kala duwan ee shahaadada beddelka CMC ee marxaladda alkalization pretreatment
1. Saamaynta heerkulka alkalization pretreatment ee heerka beddelka ee CMC
Si loo tixgeliyo saameynta heerkulka alkalization pretreatment ee heerka beddelka ee CMC ee la helay, haddii ay dhacdo hagaajinta arrimo kale sida qiyamka bilowga ah,
Xaaladaha hoos yimaada, saamaynta heerkulka alkalization pretreatment pretreatment ee shahaadada beddelka CMC ayaa laga wada hadlay, iyo natiijooyinka waxaa lagu muujiyey Fig.
Daawaynta ka hor heerkulka alkalizing/℃
Saamaynta pretreatment alkalizing heerkulka ku saabsan beddelka CMC degree
Waxaa la arki karaa in heerka beddelka CMC uu kordho kororka heerkulka alkalization pretreatment, iyo heerkulka alkalization waa 30 °C.
Heerkulka sare ee beddelka ayaa hoos u dhacaya heerkulka sii kordhaya. Tani waa sababta oo ah heerkulka alkalizing ayaa aad u hooseeya, iyo molecules-yadu aad ayay u yar yihiin oo ma awoodaan
Si wax ku ool ah u burburiyaan aagga crystalline ee cellulose, taas oo adkeyneysa wakiilka etherifying inuu galo gudaha gudaha cellulose ee marxaladda etherification, iyo heerka falcelinta waa mid aad u sarreeya.
hoose, taasoo keentay in heerka hoose ee beddelka alaabta. Si kastaba ha ahaatee, heerkulka alkalization waa inuusan noqon mid aad u sarreeya. Marka heerkulku kordho, hoos ficilka heerkulka sare iyo alkali xooggan,
Cellulose waxay u nugul tahay hoos u dhaca oksaydhka, iyo heerka beddelka badeecada CMC ayaa hoos u dhacda.
2. Saamaynta ka-hortagga daawaynta kahortagga alkalinization ee shahaadada beddelka CMC
Marka la eego xaaladda heerkulka alkalization pretreatment pretreatment waa 30 °C iyo arrimo kale waa qiyamka bilowga ah, saamaynta alkalization pretreatment time on CMC waa laga wada hadlay.
Saamaynta beddelka. Darajada beddelka
Waqtiga/saacaddii ka hor daawaynta alkalization
Saamaynta ka-hortagga ka-hortagga alkalinization-kaCMCshahaadada beddelka
Habka bulking laftiisa waa mid aad u degdeg badan, laakiin xalka alkali wuxuu u baahan yahay wakhti fidinta fiber-ka.
Waxaa la arki karaa in marka wakhtiga alkalization uu yahay 0.5-1.5h, heerka beddelka badeecada wuxuu kordhiyaa kororka waqtiga alkalization.
Heerka beddelka badeecada la helay ayaa ahayd tii ugu sarreysay markii waqtigu ahaa 1.5h, heerka beddelka ayaa hoos u dhacay kororka waqtiga ka dib 1.5h. Tani waxay kartaa
Waxay noqon kartaa sababtoo ah bilawga alkalization, iyada oo la dheereynayo wakhtiga alkalization, qulqulka alkali ee cellulose ayaa ku filan, sidaas darteed fiber-ka
Qaab dhismeedka asaasiga ah waa mid aad u dabacsan, kordhinta wakiilka etherifying iyo dhexdhexaadiyaha firfircoon
Waqtiga boostada: Abriil-26-2024