Isendlalelo Sokucwaninga
Njengomthombo wemvelo, ochichimayo futhi ovuselelekayo, i-cellulose ihlangabezana nezinselelo ezinkulu ezinhlelweni ezingokoqobo ngenxa yezakhiwo zayo ezingekho ezincibilikisiwe kanye ne-solubity elinqunyelwe. I-crystallity ephezulu kanye nama-hydrogen ama-hydrogen aphezulu asesakhiweni se-cellulose enza ukuthi ihlehlise kodwa ingancibiliki ngesikhathi senqubo yokufa, futhi ingasebenzi ngamanzi kanye nezinto eziningi eziphilayo. Ama-derivatives abo akhiqizwa ngokuchazwa kanye nokuthezeka kwamaqembu ama-hydroxll kumayunithi we-anhydroglucose ku-polymer chain, futhi azokhombisa ezinye izakhiwo ezihlukile uma ziqhathaniswa neselula yemvelo. Ukusabela kokusheshisa kwe-cellulose kungakhiqiza izitha eziningi ze-cellule cellulose, ezinjenge-methylyuli (MC), i-hpdroxyethyl cellulose (HPC) ne-hydroxyprosels (HPC) ne-hydroxyprosells (HPC), esetshenziswa kabanzi ekudleni, izimonyo, ezisetshenziswayo zemithi kanye nemithi. I-SAMELL-Sluble CE ingakha ama-polymers ahlanganiswe nge-hydrogen ngama-polycarboxylic acid kanye nama-polyphenols.
Umhlangano Wezendlalelo (i-LBL) iyindlela ephumelelayo yokulungiselela amafilimu amancane we-polymer. Lokhu okulandelayo kuchaza ikakhulukazi umhlangano we-LBL wama-CES amathathu ahlukene we-HEC, i-MC ne-HPC nge-PAA, aqhathanisa nokuziphatha komhlangano, futhi ahlaziye ithonya labanye abasebenza ngaphansi kwe-LBL. Phenya umphumela we-PH kubukhulu befilimu, kanye nokwehluka okuhlukile kwe-PH ekubumbeni amafilimu nokuchithwa, futhi kuthuthukise izakhiwo ezitholwe ngamanzi ze-CE / PAA.
Izinto zokuhlola:
I-polyacrylic acid (paa, mw = 450,000). I-viscosity ye-2WT. I-methylcellulose (MC, i-2WT. Ikhambi le-aquad elinamanzi anokuvunywa kwama-MPA angama-400 kanye ne-degree yokufaka esikhundleni sika-1.8). I-Hydroxypropylllulose (HPC, i-2WT.% Isixazululo esinamanzi nge-viscosity yama-MPA angama-400 kanye ne-degree yokufaka esikhundleni sika-2,5).
Ukulungiselela amafilimu:
Ilungiselelwe ngumhlangano we-liquid crystal ungqimba we-silicon ngo-25 ° C. Indlela yokwelashwa ye-matrix ye-slide imi kanjena: cwilisa ngesisombululo se-acidic (H2SSO4 / H2O2, 7/3VOL / VOL), bese hlambulula ngamanzi ansundu kaningana kuze kube yilapho i-PH ingathathi hlangothi, bese ekugcineni yomile nge-nitrogen emsulwa. Umhlangano we-LBL wenziwa usebenzisa imishini ezenzakalelayo. I-substrate yavele yabanjiswa ngesisombululo se-CE (0.2 MG / ML) ne-PAA solution (0.2 mg / mg / mg), isixazululo ngasinye sasigcwele amaminithi ama-4. Abathathu bageza ama-snish ama-1 min min ngalinye kwelinye lamanzi e-deionized kwenziwa phakathi kwesisombululo ngasinye sidonsa ukususa i-polymer enamathiselwe. Amanani we-PH Solution Solution kanye nesixazululo sokulungiswa sobabili salungiswa ku-PH 2.0. Amafilimu alungiselelwe alungiselelwe aboniswa njengo (CE / PAA) n, lapho n kubonisa umjikelezo womhlangano. (I-HEC / PAA) 40, (MC / PAA) 30 no (HPC / PAA) ama-30 ayelungiswa ikakhulukazi.
Ifilimu eliqhamuka kwifilimu:
I-spectra esondelene nejwayelekile yaqoshwa futhi ihlaziywe nge-nanoCalc-XR Ocean Optics, futhi ubukhulu bamafilimu afakiwe ku-silico lalinganiswa. Nge-Silicon Substrate engenalutho njengemuva, i-FT-IR Spectrum yefilimu elincanyana kwi-Silicon Substrate yaqoqwa kwi-NICOLET 8700 infrared Spectrometer.
Ukusebenzisana kwe-Hydrogen Bond phakathi kwe-PAA ne-CES:
Umhlangano we-HEC, i-MC ne-HPC nge-PAA yaba ngamafilimu we-LBL. I-infrared spectra ye-HEC / PAA, i-MC / PAA ne-HPC / PAA kukhonjisiwe kwisibalo. Izimpawu eziqinile ze-IR ze-PAA ne-CES zingabonakala ngokucacile ku-IR Spectra ye-HEC / PAA, MC / PAA ne-HPC / PAA. I-FT-IR Spectroscopy ingahlaziya ukukhishwa kwe-hydrogen bonder ukukhishwa phakathi kwe-PAA ne-CES ngokubheka ukushintshwa kwamabhande amuncu ahlukahlukene. Ukubopha kwe-hydrogen phakathi kwama-CES kanye ne-PAA ikakhulukazi kwenzeka phakathi kwe-hydroxyl axygen ye-CES kanye neCooh Group ye-PAA. Ngemuva kokuthi kusungulwe isibopho se-hydrogen, i-peak ebomvu yokwelulwa endaweni ephansi yemvamisa.
Inani eliphakeme langu-1710 cm-1 labukwa nge-PAA Powder emsulwa. Lapho i-polylacrylamide yahlangana namafilimu anama-ces ahlukene, iziqongo ze-HEC / PAA, i-MC / PAA kanye namafilimu we-MPC / 1720 cm atholakala ngo-1718 cm - 1, 1724 cm - 1, ngokulandelana. Uma kuqhathaniswa ne-PAA Powder emsulwa, ubude obuphakeme be-HPC / PAA, MC / PAA kanye namafilimu we-HEC / PAA asuswe ngu-14, 10 no-8 cm-1, ngokulandelana. Isibopho se-hydrogen phakathi komoya-mpilo we-ether kanye no-COOh baphazamisa isibopho se-hydrogen phakathi kwamaqembu e-cooh. Izibopho eziningi ze-hydrogen zakhiwa phakathi kwe-PAA ne-CE, kukhuphuka kakhulu i-Peak Shift ye-CE / PAA ku-IR Spectra. I-HPC inezinga eliphakeme kakhulu le-hydrogen bond kuyinto, i-PAA ne-MC ziphakathi, futhi i-HEC iphansi kakhulu.
Ukuziphatha kokuziphatha kwamafilimu ahlanganisiwe we-PAA ne-CES:
Ukuziphatha okwenziwe ngefilimu kwe-PAA kanye ne-CES ngesikhathi se-LBL kuphenywe kusetshenziswa i-QCM ne-Perctral interferometry. I-Qcm iyasebenza ngokuqapha ukukhula kwamafilimu e-SITU phakathi nemijikelezo yokuqala yomhlangano. Ama-interral interromters alungele amafilimu akhule ngaphezu kwemijikelezo engu-10.
Ifilimu le-HEC / PAA likhombise ukukhula okulayini kuyo yonke inqubo yomhlangano we-LBL, kanti amafilimu we-MC / PAA kanye ne-HPC / PAA akhombisa ukukhula okuvezwayo ezigabeni zokuqala zoMkhandlu bese kuguqulwa ukuba zikhule ngomugqa. Esifundeni sokukhula okuqondile, kukhuphuka izinga lokuyika, ukukhula okukhulu komjikelezo womhlangano ngamunye.
Umphumela wekhambi ph ekukhuleni kwamafilimu:
Ivelu yekhambi lithinta ukukhula kwefilimu elihlanganisiwe le-hydrogen Njenge-polyelectoryyte ebuthakathaka, i-PAA izoba yi-Ionid futhi ikhokhiswe kabi njengoba i-PH yekhambi liyanda, ngaleyo ndlela livimbisa i-Hydrogen Bond Association. Lapho izinga le-ionization of PAA lifinyelela ezingeni elithile, i-PAA ayikwazanga ukuhlangana kwifilimu enokwamukele ama-hydrogen bond kwamukelwa e-LBL.
Ukugqilazwa kwefilimu kwehle ngokwanda kwesixazululo Ph, futhi ukushuba kwefilimu kwehle ngokuzumayo ku-PH2.5 HPC / PAA ne-PH3.0-3.5 HPC / PAA. Iphuzu elibucayi le-HPC / PAA limayelana ne-PH 3.5, ngenkathi lelo hec / paa licishe libe ngu-3.0. Lokhu kusho ukuthi lapho i-PH yekhambi lomhlangano liphakeme kune-3.5, ifilimu le-HPC / PAA alikwazi ukwakhiwa, futhi lapho i-PH yesisombululo iphakeme kune-3.0, ifilimu le-HEC / PAA alikwazi ukwakhiwa. Ngenxa yezinga eliphakeme le-hydrogen bond ukukhishwa kwe-HPC / PAA membrane, inani elibucayi le-PH ye-HPC / PAA membrane liphakeme kunalolo menxa ye-HEC / PAA. Esixazululweni samahhala kasawoti, amanani abucayi we-PH wezakhiwo ezakhiwe yi-HEC / PAA, MC / PAA ne-HPC / PAA zazicishe zibe ngu-2.9, 3.2 no-3.7, ngokulandelana. I-PHP ebucayi i-HPC / PAA iphakeme kunaleyo ye-HEC / PAA, evumelana ne-LBL membrane.
Ukusebenza kokutholwa kwamanzi kwe-CE / PAA Membrane:
I-CES icebile ngamaqembu e-hydroxyl ukuze ithole ukumuncwa kwamanzi okuhle nokugcinwa kwamanzi. Ukuthatha ulwelwesi lwe-hec / i-paa ka-PAA njengesibonelo, umthamo we-adrorption we-hydrogen-bonded ce / ulwelwesi lwe-paa emanzini emvelweni wafundwa. Kuboniswa yi-interrometry ebonakalayo, ubukhulu befilimu buyanda njengoba ifilimu idonsa amanzi. Yabekwa endaweni enomswakama oguqukayo ku-25 ° C. amahora angama-24 ukufezekisa ukulingana kokutholwa kwamanzi. Amafilimu amiswe kuhhavini we-vacuum (40 ° C) ngo-24 h ukususa ngokuphelele umswakama.
Njengoba umswakama ukhula, ifilimu liyakhula. Endaweni ephansi yomswakama engama-30% -50%, ukukhula kokuqina kuhamba kancane. Lapho umswakama udlula ama-50%, ubukhulu bukhula ngokushesha. Uma kuqhathaniswa ne-hydrogen-bonded pvpon / ulwelwesi lwe-paa, ulwelwesi lwe-hec / paa lungenza amanzi amaningi emvelweni. Ngaphansi kwesimo somswakama ohlobene ka-70% (25 ° C), uhla olukhulu lwe-PVPon / PAA ifilimu lungaba ngu-4%, ngenkathi ifilimu le-HEC / PAA liphakeme cishe ngo-18%. Imiphumela ikhombisile ukuthi yize inani elithile lamaqembu oh ohlelweni lweHek / PAA libambe iqhaza ekwakhekeni kwama-hydrogen bond, bekusenenombolo enkulu yamaqembu ah axhumana namanzi emvelweni. Ngakho-ke, uhlelo lwe-HEC / PAA lunezakhiwo ezinhle zokumuncwa kwamanzi.
Ekuphetheni
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(3) Ukukhula kwe-CE / PAA film kunokuncika okuqinile kwikhambi PH. Lapho isixazululo ph siphakeme kunephuzu elibucayi, i-PAA ne-CE ngeke bahlangane kwifilimu. I-CE Eqoqekile uMefbrene yancibilika ngezixazululo eziphezulu we-PH.
(4) Njengoba ifilimu ye-CE / ye-PAA inothile ngo-Oh noCooh, ukwelashwa okushisa kwenza kube kuxhumeke okuxhunyaniswe. I-CE CRECRED CE / PAA membrane inokuqina okuhle futhi iyakhohlisa ezixazululweni eziphezulu ze-PH.
(5) Ifilimu le-CE / PAA linamandla amahle ama-adsorption wamanzi emvelweni.
Isikhathi sePosi: Feb-18-2023