Focus on Cellulose ethers

I-Synthesis kunye ne-Characterization ye-Butane Sulfonate Cellulose Ether Water Reducer

I-Synthesis kunye ne-Characterization ye-Butane Sulfonate Cellulose Ether Water Reducer

I-Microcrystalline cellulose (MCC) eneqondo eliqinisekileyo lepolymerization efunyenwe nge-acid hydrolysis ye-cellulose cotton pulp yasetyenziswa njengezinto ezikrwada. Ngaphantsi kokusebenza kwe-sodium hydroxide, yaphendulwa kunye ne-1,4-butane sultone (BS) ukufumana i-cellulose butyl sulfonate (SBC) yokunciphisa amanzi kunye ne-solubility efanelekileyo yamanzi yaphuhliswa. Ulwakhiwo lwemveliso luphawulwe nge-infrared spectroscopy (FT-IR), i-nuclear magnetic resonance spectroscopy (NMR), ukuskena i-electron microscopy (SEM), i-X-ray diffraction (XRD) kunye nezinye iindlela zokuhlalutya, kunye nesidanga sepolymerization, umlinganiselo wezinto ezikrwada, kunye nempendulo ye-MCC zaphandwa. Iziphumo zeemeko zenkqubo yokwenziwa njengeqondo lokushisa, ixesha lokuphendula, kunye nohlobo lwe-arhente yokumisa kwintsebenzo yokunciphisa amanzi kwimveliso. Iziphumo zibonisa ukuba: xa iqondo lepolymerization yezinto eziluhlaza ze-MCC ziyi-45, umlinganiselo wobunzima be-reactants: AGU (i-cellulose glucoside unit): n (NaOH): n (BS) = 1.0: 2.1: 2.2, The i-agent yokumisa i-isopropanol, ixesha lokusebenzisa izinto eziluhlaza kwiqondo lokushisa kwegumbi li-2 h, kwaye ixesha lokudibanisa imveliso yi-5 h. Xa izinga lokushisa liyi-80 ° C, imveliso efunyenweyo inezinga eliphezulu lokutshintshwa kwamaqela e-butanesulfonic acid, kwaye imveliso inomsebenzi ongcono kakhulu wokunciphisa amanzi.

Amagama angundoqo:i-cellulose; i-cellulose butylsulfonate; i-arhente yokunciphisa amanzi; ukusebenza kokunciphisa amanzi

 

1,Intshayelelo

I-concrete superplasticizer yenye yezinto eziyimfuneko kwikhonkrithi yanamhlanje. Kuchanekileyo ngenxa yokubonakala kwe-ejenti yokunciphisa amanzi ukuba ukusebenza okuphezulu, ukuqina okulungileyo kunye namandla aphezulu ekhonkrithi anokuqinisekiswa. Ukunciphisa amanzi ngoku asetyenziswa ngokubanzi ngokufanelekileyo ngokuyintloko kubandakanya ezi ndidi zilandelayo: i-naphthalene-based water reducer (SNF), i-sulfonated melamine resin-based water-reducer (SMF), i-sulfamate-based water-reducer (ASP), i-modified Lignosulfonate superplasticizer ( ML), kunye ne-polycarboxylate superplasticizer (PC), ephandwa ngokusebenzayo ngoku. Ukuhlalutya inkqubo yokwenziwa kwezinciphisi zamanzi, uninzi lwangaphambili izinciphisi zamanzi ze-condensate zangaphambili zisebenzisa i-formaldehyde enevumba elibukhali njengemathiriyeli ekrwada yokusabela kwe-polycondensation, kwaye inkqubo ye-sulfonation iqhutywa ngokubanzi nge-asidi yesulfuric etshisayo okanye i-asidi yesulfuric exubileyo. Oku ngokuqinisekileyo kuya kubangela iziphumo ezibi kubasebenzi kunye nokusingqongileyo, kwaye kuya kuvelisa umthamo omkhulu wentsalela yenkunkuma kunye nolwelo olulahlwayo, olungabangeli uphuhliso oluzinzileyo; nangona kunjalo, nangona i-polycarboxylate yokunciphisa amanzi ineenzuzo zelahleko encinci yekhonkrithi ngokuhamba kwexesha, idosi ephantsi, ukuhamba kakuhle Ineenzuzo zokuxinana okuphezulu kwaye akukho zinto ezinobuthi ezifana ne-formaldehyde, kodwa kunzima ukuyikhuthaza e-China ngenxa yokuphakama okuphezulu. ixabiso. Ukususela kuhlalutyo lomthombo wezinto eziluhlaza, akunzima ukufumanisa ukuba uninzi lwezinciphisi zamanzi ezikhankanywe ngasentla zenziwe ngokusekwe kwimveliso yepetrochemical / ngemveliso, ngelixa i-petroleum, njengesixhobo esingahlaziywayo, iyancipha kwaye iyancipha. ixabiso layo lihlala linyuka. Ke ngoko, indlela yokusebenzisa izixhobo zendalo ezinokuthi zihlaziywe ngexabiso eliphantsi kunye nentabalala njengemathiriyeli ekrwada ukuphuhlisa ii-superplasticizer zekonkrithi ezisebenza ngokuphezulu ziye zaba lukhokelo lophando olubalulekileyo kwii-superplasticizers zekhonkrithi.

I-Cellulose yi-macromolecule yomgca eyenziwe ngokudibanisa ezininzi ze-D-glucopyranose kunye ne-β- (1-4) i-glycosidic bonds. Kukho amaqela amathathu e-hydroxyl kwiringi yeglucopyranosyl nganye. Unyango olululo lunokufumana i-reactivity ethile. Kweli phepha, i-cellulose cotton pulp yayisetyenziswe njengento yokuqala ekrwada, kwaye emva kwe-acid hydrolysis ukufumana i-cellulose ye-microcrystalline kunye neqondo elifanelekileyo le-polymerization, yenziwe i-sodium hydroxide kwaye iphendule nge-1,4-butane sultone ukulungiselela i-butyl sulfonate Acid. I-cellulose ether superplasticizer, kunye nemiba echaphazelayo yempendulo nganye yaxoxwa.

 

2. Linge

2.1 Iimathiriyeli ekrwada

I-cellulose cotton pulp, i-polymerization degree 576, i-Xinjiang Aoyang Technology Co., Ltd.; I-1,4-butane sultone (BS), ibakala loshishino, eliveliswe yiShanghai Jiachen Chemical Co., Ltd.; I-52.5R yesamente eqhelekileyo yasePortland, eUrumqi Ibonelelwe ngumzi mveliso wesamente; I-China ISO yesanti esemgangathweni, eveliswe yi-Xiamen Ace Ou Standard Sand Co., Ltd.; i-sodium hydroxide, i-hydrochloric acid, i-isopropanol, i-anhydrous methanol, i-ethyl acetate, i-n-butanol, i-petroleum ether, njl., zonke zihlambulukile ngokuhlalutyayo, zifumaneka ngokurhweba.

2.2 Indlela yovavanyo

Ukulinganisa umlinganiselo othile we-cotton pulp kwaye uyicole ngokufanelekileyo, uyifake kwibhotile yentamo emithathu, yongeza i-concentration ethile ye-dilute hydrochloric acid, ivuselele ukutshisa kunye ne-hydrolyze ixesha elithile, ipholile ukuya kwiqondo lokushisa, ihluzo, hlamba ngamanzi de ungathathi hlangothi, kwaye ucoceke ngo-50 ° C ukuze ufumane Emva kokuba ne-microcrystalline cellulose imathiriyeli ekrwada kunye namaqondo ahlukeneyo e-polymerization, ukulinganisa iqondo labo lokupholisa ngokuhambelana noncwadi, lubeke kwibhotile yokuphendula enentamo ezintathu, yimise nge. i-agent exhomayo amaxesha angama-10 ubukhulu bayo, yongeza inani elithile lesisombululo se-sodium hydroxide yamanzi phantsi kokuvuselela, Gxuma kwaye usebenze kwiqondo lobushushu begumbi ixesha elithile, yongeza inani elibaliweyo le-1,4-butane sultone (BS), ukufudumala kubushushu bokusabela, sabela kubushushu obungaguqukiyo kangangexesha elithile, zipholisa imveliso kwiqondo lobushushu begumbi, kwaye ufumane imveliso ekrwada ngokufunxa. Hlanza ngamanzi kunye ne-methanol ngamaxesha e-3, kwaye ukucoca ngokufunxa ukufumana imveliso yokugqibela, oko kukuthi i-cellulose butylsulfonate water reducer (SBC).

2.3 Uhlalutyo lwemveliso kunye nokuchazwa kwabalinganiswa

2.3.1 Ukumiselwa komxholo wesalfure wemveliso kunye nokubalwa kweqondo lokutshintshwa

I-FLASHEA-PE2400 i-elemental analyzer yasetyenziselwa ukwenza uhlalutyo olusisiseko kwi-cellulose eyomileyo ye-butyl sulfonate imveliso yokunciphisa amanzi ukuze kuqinisekiswe umxholo wesulfure.

2.3.2 Ukumiselwa kobumanzi bodaka

Ilinganiswe ngokwe-6.5 kwi-GB8076-2008. Oko kukuthi, ukulinganisa kuqala umxube wamanzi / wesamente / oqhelekileyo wesanti kwi-NLD-3 sement sodaka fluidity tester xa i-diameter yokwandisa (180±2)mm. isamente, umlinganiselo wokusetyenziswa kwamanzi okulinganisa ngama-230g), uze wongeze i-arhente yokunciphisa amanzi obunzima bayo buyi-1% yobunzima besamente emanzini, ngokwesamente/iarhente yokunciphisa amanzi/amanzi aqhelekileyo/isanti esemgangathweni=450g/4.5g/ I-230 g / Umlinganiselo we-1350 g ubekwe kwi-JJ-5 yomxube we-samente yodaka kwaye ixutywe ngokulinganayo, kunye nobubanzi obuninzi bodaka kwi-motar fluidity tester iyalinganiswa, into elinganisiweyo yodaka lwe-fluidity.

2.3.3 Ubume beMveliso

Isampulu ibonakaliswe yi-FT-IR usebenzisa i-EQUINOX 55 uhlobo lwe-Fourier ukuguqula i-infrared spectrometer yeNkampani ye-Bruker; I-spectrum ye-H NMR yesampulu iphawulwe ngesixhobo se-INOVA ZAB-HS sokulima i-superconducting nuclear magnetic resonance isixhobo se-Varian Company; I-morphology yemveliso yabonwa phantsi kwe-microscope; Uhlalutyo lwe-XRD lwenziwa kwisampulu ngokusebenzisa i-X-ray diffractometer ye-MAC Company M18XHF22-SRA.

 

3. Iziphumo kunye nengxoxo

3.1 Iziphumo zomlinganiswa

3.1.1 Iziphumo zophawu lweFT-IR

Uhlalutyo lwe-infrared lwenziwa kwi-cellulose ye-microcrystalline ekrwada kunye neqondo le-polymerization Dp = 45 kunye nemveliso ye-SBC eyenziwe kule mveliso ekrwada. Kuba iincopho zokufunxa ze-SC kunye ne-SH zibuthathaka kakhulu, azifanelekanga ukuchongwa, ngelixa i-S=O inencopho eyomeleleyo yokufunxa. Ngoko ke, ingaba kukho iqela le-sulfonic acid kwisakhiwo se-molecular inokumiselwa ngokuqinisekisa ubukho be-S = O peak. Ngokucacileyo, kwi-spectrum ye-cellulose, kukho incopho eyomeleleyo yokufunxa kwinani lamaza elingama-3344 cm-1, elibalelwa kwincopho ye-hydroxyl yokwelula i-vibration kwi-cellulose; Incopho yokufunxa eyomeleleyo kwinani lamaza angama-2923 cm-1 yincopho yokungcangcazela kwe-methylene (-CH2). Incopho yokungcangcazela; uthotho lweebhendi ezenziwe nge-1031, 1051, 1114, kunye ne-1165cm-1 zibonisa incopho yokufunxa ye-hydroxyl yokwelula i-vibration kunye nencopho yokufunxa ye-ether bond (COC) yokugoba ukungcangcazela; inombolo yamaza i-1646cm-1 ibonisa i-hydrogen eyenziwe yi-hydroxyl kunye namanzi asimahla Incopho yokufunxa ibhondi; ibhendi ye-1432 ~ 1318cm-1 ibonisa ubukho be-cellulose crystal structure. Kwi-spectrum ye-IR ye-SBC, ukuqina kwebhendi 1432 ~ 1318cm-1 buthathaka; ngelixa ubuninzi be-absorption peak kwi-1653 cm-1 inyuka, ebonisa ukuba ukukwazi ukwenza iibhondi ze-hydrogen kuqiniswa; I-1040, i-605cm-1 ibonakala yomelele iincopho zokufunxa, kwaye ezi zimbini azibonakali kwi-infrared spectrum ye-cellulose, yangaphambili yimpawu ye-absorption ye-S=O bond, kwaye le yokugqibela yimpawu ye-absorption ye-SO bond. Ngokusekelwe kolu hlalutyo lungentla, kunokubonwa ukuba emva kokuphendula kwe-etherification ye-cellulose, kukho amaqela e-sulfonic acid kwi-chain yayo ye-molecular.

3.1.2 Iziphumo ze-H NMR zeempawu

I-spectrum ye-H NMR ye-cellulose butyl sulfonate ingabonwa: ngaphakathi kwe-γ=1.74 ~ 2.92 yi-hydrogen proton yekhemikhali yokutshintshwa kwe-cyclobutyl, kwaye ngaphakathi kwe-γ=3.33 ~ 4.52 yiyunithi ye-cellulose anhydroglucose Ukutshintshwa kweekhemikhali ze-oxygen proton kwi-γ=4.52 ~6 kukutshintshwa kweekhemikhali zeproton ye-methylene kwiqela le-asidi ye-butylsulfonic edityaniswe ne-oksijini, kwaye akukho ncopho ku-γ=6 ~ 7, ebonisa ukuba imveliso ayikho Ezinye iiprotons zikhona.

3.1.3 Iziphumo zokulinganiswa kwe-SEM

Ukuqwalaselwa kwe-SEM ye-cellulose cotton pulp, i-microcrystalline cellulose kunye nemveliso ye-cellulose butylsulfonate. Ngokuhlalutya iziphumo zokuhlalutya kwe-SEM ye-cellulose cotton pulp, i-microcrystalline cellulose kunye nemveliso ye-cellulose butanesulfonate (SBC), kufunyenwe ukuba i-microcrystalline cellulose efunyenwe emva kwe-hydrolysis kunye ne-HCL inokutshintsha kakhulu isakhiwo se-cellulose fibers. Isakhiwo se-fibrous satshatyalaliswa, kwaye iincinci ze-cellulose ze-agglomerated zafunyanwa. I-SBC efunyenwe ngokusabela ngokuqhubekayo kunye ne-BS yayingenayo i-fibrous structure kwaye iguqulwe ngokusisiseko ibe yi-amorphous structure, eyayiluncedo ekuchithweni kwayo emanzini.

3.1.4 Iziphumo zeempawu zeXRD

I-crystallinity ye-cellulose kunye ne-derivatives yayo ibhekisela kwipesenti yommandla we-crystalline owenziwe yiyunithi yeyunithi ye-cellulose iyonke. Xa i-cellulose kunye ne-derivatives yayo ithatha i-chemical reaction, i-hydrogen bonds kwi-molecule kunye naphakathi kwe-molecule iyatshatyalaliswa, kwaye ummandla we-crystalline uya kuba ngummandla we-amorphous, ngaloo ndlela unciphisa i-crystallinity. Ngoko ke, utshintsho lwe-crystallinity ngaphambi nangemva kokuphendula ngumlinganiselo we-cellulose Enye yeenqobo zokuthatha inxaxheba kwimpendulo okanye cha. Uhlalutyo lwe-XRD lwenziwa kwi-microcrystalline cellulose kunye nemveliso ye-cellulose butanesulfonate. Ingabonwa ngokuthelekisa ukuba emva kwe-etherification, i-crystallinity itshintsha ngokusisiseko, kwaye umkhiqizo uguqule ngokupheleleyo kwisakhiwo se-amorphous, ukwenzela ukuba inyibilike emanzini.

3.2 Ifuthe leqondo lepolymerization yemathiriyeli ekrwada ekusebenzeni kokunciphisa amanzi kwimveliso

I-fluidity yomdaka ibonakalisa ngokuthe ngqo ukusebenza kokunciphisa amanzi kwimveliso, kwaye umxholo wesulfure wemveliso yenye yezona zinto zibalulekileyo ezichaphazela umbane wodaka. I-fluidity yodaka ilinganisa ukusebenza kokunciphisa amanzi kwimveliso.

Emva kokutshintsha iimeko zokusabela kwe-hydrolysis ukulungiselela i-MCC ngamaqondo ahlukeneyo epolymerization, ngokutsho kwendlela engentla, khetha inkqubo ethile yokudibanisa ukulungiselela iimveliso ze-SBC, ukulinganisa umxholo wesulfure ukubala isidanga sokutshintshwa kwemveliso, kwaye udibanise iimveliso ze-SBC emanzini. /isamente/isixokelelwano esiqhelekileyo sokuxutywa kwesanti Ukulinganisa ukumanzi kodaka.

Inokubonwa kwiziphumo zovavanyo ukuba ngaphakathi koluhlu lophando, xa i-polymerization degree ye-microcrystalline cellulose izinto eziluhlaza ziphezulu, umxholo wesulfure (i-substitution degree) yemveliso kunye nokukhupha udaka kuphantsi. Oku kungenxa yokuba: ubunzima be-molecular ye-raw material encinci, ehambelana nokuxuba okufanayo kwezinto eziluhlaza kunye nokungena kwe-etherification agent, ngaloo ndlela kuphuculwe iqondo le-etherification yemveliso. Nangona kunjalo, izinga lokunciphisa amanzi emveliso alinyuki kumgca othe ngqo kunye nokuncipha kweqondo le-polymerization yemathiriyeli ekrwada. Iziphumo zovavanyo zibonisa ukuba i-motar fluidity yomxube we-cement mortar exutywe ne-SBC elungiselelwe ngokusebenzisa i-microcrystalline cellulose kunye neqondo le-polymerization Dp <96 (ubunzima be-molecular <15552) inkulu kune-180 mm (enkulu kunoko ngaphandle kokunciphisa amanzi) . i-benchmark fluidity), ebonisa ukuba i-SBC inokulungiswa ngokusebenzisa i-cellulose enobunzima be-molecular obungaphantsi kwe-15552, kunye nomlinganiselo othile wokunciphisa amanzi unokufumaneka; I-SBC ilungiselelwe ngokusebenzisa i-cellulose ye-microcrystalline kunye neqondo le-polymerization ye-45 (ubunzima be-molecular: 7290), kwaye yongezwa kumxube wekhonkrithi , umbane olinganisiweyo wodaka ngowona mkhulu, ngoko kuqwalaselwa ukuba i-cellulose kunye neqondo le-polymerization. malunga ne-45 ilungele kakhulu ukulungiswa kwe-SBC; xa iqondo le-polymerization yezinto eziluhlaza likhulu kune-45, ubuninzi bomdaka buyancipha ngokuthe ngcembe, oku kuthetha ukuba izinga lokunciphisa amanzi liyancipha. Oku kungenxa yokuba xa ubunzima be-molecular bukhulu, kwelinye icala, i-viscosity yenkqubo yomxube iya kwanda, ukungafani kwe-dispersion ye-samente kuya kuba nzima, kwaye ukusabalalisa kwikhonkrithi kuya kucotha, okuya kuchaphazela umphumo wokusabalalisa; kwelinye icala, xa ubunzima bemolekyuli bukhulu, I-macromolecules ye-superplasticizer ikwi-coil conformation engahleliweyo, ekunzima ukuyithengisa kumphezulu wamasuntswana e-samente. Kodwa xa iqondo le-polymerization yezinto eziluhlaza lingaphantsi kwama-45, nangona umxholo wesulfure (i-degree substitution) yemveliso inkulu kakhulu, i-fluidity yomxube wodaka nayo iqala ukuhla, kodwa ukuncipha kuncinci kakhulu. Isizathu kukuba xa ubunzima be-molecular ye-agent yokunciphisa amanzi buncinci, nangona i-molecular diffusion ilula kwaye inokumanzisa okulungileyo, ukukhawuleza kwe-adsorption ye-molecule inkulu kune-molecule, kwaye ikhonkco lokuthuthwa kwamanzi lifutshane kakhulu. kwaye ukungqubana phakathi kwamasuntswana kukhulu, okuyingozi kwikhonkrithi. Impembelelo yokusasazwa ayilunganga njengaleyo yokunciphisa amanzi kunye nobunzima obukhulu bemolekyuli. Ngoko ke, kubaluleke kakhulu ukulawula ngokufanelekileyo ubunzima be-molecular ye-pig face (icandelo le-cellulose) ukuphucula ukusebenza kokunciphisa amanzi.

3.3 Impembelelo yeemeko zokusabela kwindlela yokunciphisa amanzi kwimveliso

Kufunyaniswa ngovavanyo ukuba ukongeza kwinqanaba le-polymerization ye-MCC, umlinganiselo wee-reactants, ubushushu bokusabela, ukusebenza kwezinto ezikrwada, ixesha lokwenziwa kwemveliso, kunye nohlobo lwe-arhente yokumisa zonke zichaphazela ukusebenza kokunciphisa amanzi kwimveliso.

3.3.1 Umlinganiselo wereactant

(1) Umthamo we-BS

Ngaphantsi kweemeko ezichongiweyo zezinye iiparameters zenkqubo (iqondo le-polymerization ye-MCC yi-45, n (MCC): n (NaOH) = 1: 2.1, i-agent yokumisa i-isopropanol, ixesha lokusebenzisa i-cellulose kwiqondo lokushisa le-2h, iqondo lobushushu synthesis yi 80 ° C, kunye nexesha synthesis 5h), ukuphanda isiphumo isixa arhente etherification 1,4-butane sultone (BS) kwiqondo lokutshintshwa kwamaqela butanesulfonic acid imveliso kunye fluidity of the udaka.

Ingabonwa ukuba njengoko inani le-BS linyuka, iqondo lokutshintshwa kwamaqela e-butanesulfonic acid kunye nokunyuka kwamanzi omdaka kwanda kakhulu. Xa umlinganiselo we-BS ukuya kwi-MCC ufikelela kwi-2.2: 1, i-fluidity ye-DS kunye nodaka lufikelela phezulu. ixabiso, kucingwa ukuba ukusebenza kokunciphisa amanzi yeyona nto ilungileyo ngeli xesha. Ixabiso le-BS laqhubeka likhula, kwaye zombini idigri yokutshintshwa kunye nokumanzi komdaka kwaqala ukuncipha. Oku kungenxa yokuba xa i-BS igqithise, i-BS iya kusabela nge-NaOH ukuvelisa i-HO-(CH2)4SO3Na. Ngoko ke, eli phepha likhetha umlinganiselo wezinto eziphathekayo we-BS kwi-MCC njenge-2.2: 1.

(2) Umthamo weNaOH

Ngaphantsi kweemeko ezinqunywe ngezinye iiparameters zenkqubo (iqondo le-polymerization ye-MCC yi-45, n (BS): n (MCC) = 2.2: 1. I-agent yokumisa i-isopropanol, ixesha lokusebenzisa i-cellulose kwiqondo lokushisa le-2h, ubushushu bokudibanisa yi-80 ° C, kunye nexesha le-synthesis ye-5h), ukuphanda umphumo wesixa se-sodium hydroxide kwiqondo lokutshintshwa kwamaqela e-butanesulfonic acid kwimveliso kunye ne-fluidity of mortar.

Ingabonwa ukuba, ngokunyuka kwexabiso lokunciphisa, iqondo lokutshintshwa kwe-SBC landa ngokukhawuleza, kwaye liqala ukuhla emva kokufikelela kwixabiso eliphezulu. Oku kungenxa yokuba, xa umxholo we-NaOH uphezulu, kukho iziseko ezininzi zamahhala kwinkqubo, kwaye amathuba okuphendula kwecala ayanda, okubangela ukuba i-etherification agents (BS) zithathe inxaxheba kwiimpendulo zecala, ngaloo ndlela zinciphisa iqondo lokutshintshwa kwe-sulfonic. amaqela acid kwimveliso. Kwiqondo lokushisa eliphezulu, ubukho be-NaOH eninzi buya kunciphisa i-cellulose, kwaye ukusebenza kokunciphisa amanzi kwimveliso kuya kuchaphazeleka kwinqanaba eliphantsi le-polymerization. Ngokweziphumo zovavanyo, xa umlinganiselo we-molar we-NaOH ukuya kwi-MCC malunga ne-2.1, i-degree of substitution inkulu, ngoko eli phepha linquma ukuba i-molar ratio ye-NaOH kwi-MCC yi-2.1: 1.0.

3.3.2 Impembelelo yobushushu bokusabela kwimveliso yokunciphisa amanzi

Ngaphantsi kweemeko ezichongiweyo zezinye iiparameters zenkqubo (iqondo le-polymerization ye-MCC yi-45, n (MCC):n (NaOH): n (BS) = 1: 2.1: 2.2, i-arhente yokumisa i-isopropanol, kunye nexesha lokuqalisa i-cellulose kwindawo yokushisa i-2h Ixesha le-5h), impembelelo ye-synthesis reaction yeqondo lokushisa kwinqanaba lokutshintshwa kwamaqela e-butanesulfonic acid kwimveliso yaphandwa.

Inokubonwa ukuba njengoko iqondo lobushushu reaction linyuka, iqondo le-sulfonic acid substitution DS ye-SBC iyanda ngokuthe ngcembe, kodwa xa iqondo lobushushu lokusabela lidlula i-80 °C, i-DS ibonisa ukuhla. Ukusabela kwe-etherification phakathi kwe-1,4-butane sultone kunye ne-cellulose yi-endothermic reaction, kwaye ukwandisa ukushisa kwe-reaction kunenzuzo ekuphenduleni phakathi kwe-etherifying agent kunye neqela le-cellulose hydroxyl, kodwa ngokunyuka kweqondo lokushisa, umphumo we-NaOH kunye ne-cellulose yanda ngokuthe ngcembe. . Iba namandla, ibangela ukuba i-cellulose ihlaziywe kwaye iwe, okubangela ukuhla kwe-molecular weight of cellulose kunye nokuveliswa kweeshukela ezincinci ze-molecular. Ukusabela kwezi molekyuli ezincinci kunye ne-etherifying agents kulula, kwaye i-etherifying agents ziya kudliwa, ezichaphazela iqondo lokutshintshwa kwemveliso. Ke ngoko, le ithisisi ithathela ingqalelo ukuba eyona qondo lobushushu lifanelekileyo lokusabela kwe-etherification ye-BS kunye neselulosi yi-80℃.

3.3.3 Impembelelo yexesha lokusabela kwimveliso yokunciphisa amanzi

Ixesha lokuphendula lihlulwe libe yi-activation yeqondo lokushisa kwegumbi lezinto eziluhlaza kunye nexesha eliqhubekayo lokudibanisa ubushushu beemveliso.

(1) Ixesha lokuqalisa ubushushu begumbi lezinto ezikrwada

Ngaphantsi kwezi meko ziphezulu zenkqubo (i-MCC degree of polymerization yi-45, n(MCC):n(NaOH):n(BS)=1:2.1:2.2, i-agent yokumisa i-isopropanol, i-synthesis reaction yeqondo lokushisa yi-80 ° C, imveliso Ixesha le-synthesis yeqondo lokushisa rhoqo 5h), phanda ifuthe lexesha lokuvula ubushushu begumbi kwiqondo lokutshintshwa kweqela lemveliso ye-butanesulfonic acid.

Ingabonwa ukuba iqondo lokutshintshwa kweqela le-butanesulfonic acid yemveliso ye-SBC inyuka kuqala kwaye iyancipha ngokunyuka kwexesha lokuqalisa. Isizathu sokuhlalutya sinokuthi ngokunyuka kwexesha lesenzo se-NaOH, ukuthotywa kwe-cellulose kunzulu. Ukunciphisa ubunzima bemolekyuli yeselulosi ukwenza iswekile encinci yemolekyuli. Ukusabela kwezi molekyuli ezincinci kunye ne-etherifying agents kulula, kwaye i-etherifying agents ziya kudliwa, ezichaphazela iqondo lokutshintshwa kwemveliso. Ngoko ke, eli phepha liqwalasela ukuba ixesha lokuvula ukushisa kwegumbi lezinto eziluhlaza yi-2h.

(2) Ixesha lokudibanisa imveliso

Ngaphantsi kweemeko ezichanekileyo zenkqubo apha ngasentla, umphumo wexesha lokuqalisa kwiqondo lokushisa lokushisa kwinqanaba lokutshintshwa kweqela le-butanesulfonic acid yemveliso yaphandwa. Ingabonwa ukuba ngokunyuka kwexesha lokuphendula, iqondo lokutshintshwa kuqala linyuka, kodwa xa ixesha lokuphendula lifikelela kwi-5h, i-DS ibonisa ukuhla. Oku kuhambelana nesiseko samahhala esikhoyo kwi-etherification reaction ye-cellulose. Kumaqondo obushushu aphezulu, ukolulwa kwexesha lokuphendula kukhokelela ekwandeni kwenqanaba le-alkali hydrolysis yeselulosi, ukucutha kwekhonkco le-cellulose yemolekyuli, ukuhla kobunzima bemolekyuli yemveliso, kunye nokwanda kokuchaneka kwecala, okukhokelela ekubeni endaweni. isidanga siyehla. Kolu vavanyo, ixesha elifanelekileyo le-synthesis yi-5h.

3.3.4 Isiphumo sohlobo lwe-arhente yokuxhoma kwindlela yokunciphisa amanzi kwimveliso.

Ngaphantsi kweemeko ezifanelekileyo zenkqubo (i-MCC i-polymerization degree yi-45, n (MCC):n (NaOH):n(BS)=1:2.1:2.2, ixesha lokusebenzisa izinto eziluhlaza kwiqondo lokushisa liyi-2h, ixesha le-synthesis yeqondo lokushisa rhoqo. yeemveliso yi-5h, kunye ne-synthesis reaction lokushisa i-80 ℃), ngokulandelelana khetha i-isopropanol, i-ethanol, i-n-butanol, i-ethyl acetate kunye ne-ether ye-petroleum njenge-agent yokumisa, kwaye uxoxe ngempembelelo yabo ekusebenzeni kokunciphisa amanzi kwimveliso.

Ngokucacileyo, i-isopropanol, i-n-butanol kunye ne-ethyl acetate zonke zingasetyenziswa njenge-arhente yokumisa kule mpendulo ye-etherification. Indima ye-arhente yokumisa, ngaphezu kokusabalalisa i-reactants, inokulawula ubushushu bokusabela. Indawo yokubilisa ye-isopropanol yi-82.3 ° C, ngoko ke i-isopropanol isetyenziswa njenge-arhente yokumisa, ubushushu benkqubo bunokulawulwa kufuphi neqondo eliphezulu lokuphendula, kunye neqondo lokutshintshwa kwamaqela e-butanesulfonic acid kwimveliso kunye nokumanzi kwamanzi. udaka luphezulu ngokwentelekiso; ngelixa indawo yokubilisa ye-ethanol iphezulu kakhulu, iqondo lokushisa alihambisani neemfuno, iqondo lokutshintshwa kwamaqela e-butanesulfonic acid kwimveliso kunye ne-fluidity ye-mortar iphantsi; I-petroleum ether inokuthatha inxaxheba kwi-reaction, ngoko ke akukho mveliso echithwayo inokufumaneka.

 

4 Isiphelo

(1) Ukusebenzisa i-cotton pulp njengento yokuqala ekrwada,i-microcrystalline cellulose (MCC)kunye neqondo elifanelekileyo lepolymerization yalungiswa, isebenze yi-NaOH, kwaye iphendule nge-1,4-butane sultone ukulungiselela i-asidi e-soluble butylsulfonic acid Cellulose ether, oko kukuthi, i-cellulose-based reducer yamanzi. Ubume bemveliso bubonakaliswe, kwaye kwafunyaniswa ukuba emva kokuphendula kwe-etherification ye-cellulose, kwakukho amaqela e-sulfonic acid kwi-chain yayo ye-molecular, eyaye yaguqulwa yaba yi-amorphous structure, kwaye imveliso yokunciphisa amanzi ine-solubility efanelekileyo yamanzi;

(2) Ngokusebenzisa iimvavanyo, kufunyenwe ukuba xa iqondo le-polymerization ye-microcrystalline cellulose i-45, ukusebenza kokunciphisa amanzi kwimveliso efunyenweyo iyona nto ibhetele; phantsi kwemeko yokuba iqondo lepolymerization yezinto eziluhlaza lichongiwe, umlinganiselo we-reactants ngu-n(MCC):n(NaOH):n(BS)=1:2.1:2.2, ixesha lokuvula lezinto eziluhlaza kwiqondo lobushushu begumbi I-2h, ukushisa kwemveliso ye-synthesis yi-80 ° C, kwaye ixesha lokudibanisa yi-5h. Ukusebenza kwamanzi kulungile.


Ixesha lokuposa: Feb-17-2023
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