Okuphuma kokuphuma emanzini kwe-cellulose ether

I-crosslinking mechanism, indlela kanye nezakhiwo zezinhlobo ezahlukene ze-crosslinking agents kanye ne-ether-soluble cellulose ether yethulwa. Ngokuguqulwa kwe-crosslinking, i-viscosity, izakhiwo ze-rheological, ukuncibilika kanye nezakhiwo zemishini ze-ether ye-cellulose encibilikayo emanzini zingathuthukiswa kakhulu, ukuze kuthuthukiswe ukusebenza kwayo kokusetshenziswa. Ngokusho kwesakhiwo samakhemikhali kanye nezakhiwo zama-crosslinkers ahlukene, izinhlobo zokusabela kokuguqulwa kwe-cellulose ether crosslinking zafingqwa, futhi izikhombisi-ndlela zokuthuthukiswa kwama-crosslinkers ahlukene emikhakheni ehlukahlukene yokusetshenziswa kwe-cellulose ether zafingqwa. Uma kubhekwa ukusebenza okuhle kakhulu kwe-ether ye-cellulose encibilikayo emanzini elungiswe ngokuxhumanisa kanye nezifundo ezimbalwa ekhaya naphesheya, ukuguqulwa kwe-crosslinking okuzayo kwe-cellulose ether kunamathemba abanzi entuthuko. Lokhu okokubhekisela kubacwaningi abafanelekile kanye namabhizinisi okukhiqiza.
Amagama angukhiye: ukuguqulwa kwe-crosslinking; I-cellulose ether; Isakhiwo samakhemikhali; Ukuncibilika; Ukusebenza kohlelo lokusebenza

I-Cellulose ether ngenxa yokusebenza kwayo okuhle kakhulu, njenge-ejenti yokuqina, i-ejenti yokugcina amanzi, i-adhesive, i-binder ne-disperant, i-colloid evikelayo, i-stabilizer, i-ejenti yokumiswa, i-emulsifier kanye ne-ejenti yokwakha ifilimu, esetshenziswa kabanzi ekugqokeni, ekwakhiweni, e-petroleum, amakhemikhali nsuku zonke, ukudla. kanye nezimboni zemithi nezinye. I-cellulose ether ikakhulukazi ihlanganisa i-methyl cellulose,i-hydroxyethyl cellulose,i-carboxymethyl cellulose, i-ethyl cellulose, i-hydroxypropyl methyl cellulose, i-hydroxyethyl methyl cellulose nezinye izinhlobo ze-ether exubile. I-Cellulose ether yenziwe ngefayibha kakotini noma i-wood fiber nge-alkalization, i-etherification, ukugeza i-centrifugation, ukomisa, inqubo yokugaya elungisiwe, ukusetshenziswa kwe-etherification agents ngokuvamile zisebenzisa i-halogenated alkane noma i-epoxy alkane.
Kodwa-ke, ekusetshenzisweni kwe-ether ye-cellulose encibilikayo emanzini, amathuba azohlangana nemvelo ekhethekile, njengezinga lokushisa eliphezulu neliphansi, imvelo ye-acid-base, imvelo eyinkimbinkimbi ye-ionic, lezi zindawo zizobangela ukuqina, ukuncibilika, ukugcinwa kwamanzi, ukunamathela, ukunamathela, ukumiswa okuzinzile kanye ne-emulsification ye-ether ye-cellulose encibilikayo emanzini kuthinteka kakhulu, futhi kuholele ekulahlekelweni okuphelele kokusebenza kwayo.
Ukuze kuthuthukiswe ukusebenza kwesicelo se-cellulose ether, kuyadingeka ukwenza ukwelashwa kwe-crosslinking, usebenzisa ama-agent ahlukene okuxhumanisa, ukusebenza komkhiqizo kuhlukile. Ngokusekelwe ocwaningweni lwezinhlobo ezahlukene ze-crosslinking agents kanye nezindlela zabo zokuxhumanisa, kuhlanganiswe nobuchwepheshe bokuxhumanisa inqubo yokukhiqiza yezimboni, leli phepha lixoxa ngokuxhunywa kwe-cellulose ether nezinhlobo ezahlukene ze-crosslinking agents, linikeza ireferensi yokuguqulwa kokuxhumanisa kwe-cellulose ether. .

1.Isakhiwo kanye nomgomo wokuxhumanisa we-cellulose ether

I-cellulose etheriwuhlobo lokuphuma kokuphuma ku-cellulose, oluhlanganiswa ukusabela kokufakwa esikhundleni kwe-ether kwamaqembu amathathu e-alcohol hydroxyl kuma-molecule emvelo we-cellulose kanye ne-halogenated alkane noma i-epoxide alkane. Ngenxa yomehluko wama-substituents, ukwakheka kanye nezakhiwo ze-cellulose ether zihlukile. Ukusabela okuhlanganayo kwe-cellulose ether ikakhulukazi kuhilela i-etherification noma i-esterification ye--OH (OH eringini yeyunithi ye-glucose noma i-OH endaweni ebambele noma i-carboxyl endaweni ebambele) kanye ne-ejenti exhumanisayo enamaqembu kanambambili noma amaningi asebenzayo, ukuze amabili noma ama-molecule e-cellulose ether amaningi axhunywe ndawonye ukuze akhe uhlaka lwenethiwekhi yendawo ebanzi. Lokho kuyi-crosslinked cellulose ether.
Ngokuvamile, i-cellulose ether kanye ne-crosslinking agent yesisombululo samanzi esiqukethe okuningi -OH njenge-HEC, HPMC, HEMC, MC kanye ne-CMC kungenziwa i-etherified noma i-esterified crosslinked. Ngenxa yokuthi i-CMC iqukethe ama-ion e-carboxylic acid, amaqembu asebenzayo ku-ejenti exhumanisayo angahlanganiswa ahlanganiswe nama-ion e-carboxylic acid.
Ngemuva kokusabela kwe- -OH noma -COO- ku-cellulose ether molecule ene-agent exhumanisayo, ngenxa yokuncipha kokuqukethwe kwamaqembu ancibilikayo emanzini kanye nokwakhiwa kwesakhiwo senethiwekhi esinezinhlangothi eziningi esixazululweni, ukuncibilika kwayo, i-rheology kanye nezakhiwo zemishini. izoshintshwa. Ngokusebenzisa ama-agent ahlukene okuxhumanisa ukuze asabele nge-cellulose ether, ukusebenza kokufakwa kwe-cellulose ether kuzothuthukiswa. I-cellulose ether elungele ukusetshenziswa kwezimboni yalungiswa.

2. Izinhlobo zama-crosslinking agents

2.1 Ama-aldehydes crosslinking agents
Ama-aldehyde crosslinking agents abhekisela kumakhemikhali ephilayo aqukethe i-aldehyde group (-CHO), asebenza ngamakhemikhali futhi angasabela nge-hydroxyl, ammonia, amide nezinye izinhlanganisela. Ama-aldehyde crosslinking agents asetshenziselwa i-cellulose kanye nokuphuma kwawo ahlanganisa i-formaldehyde, i-glyoxal, i-glutaraldehyde, i-glyceraldehyde, njll. Iqembu le-Aldehyde lingasabela kalula ngama-OH amabili ukuze akhe ama-acetal ngaphansi kwezimo ze-asidi ebuthakathaka, futhi ukusabela kuyabuyiselwa emuva. Ama-cellulose ether ajwayelekile alungiswa ama-aldehydes crosslinking agents yi-HEC, HPMC, HEMC, MC, CMC kanye namanye ama-cellulose ethers.
Iqembu elilodwa le-aldehyde lixhunyaniswe namaqembu amabili e-hydroxyl ku-cellulose ether molecular chain, futhi ama-molecule e-cellulose ether axhunywe ngokwakhiwa kwama-acetal, akhe isakhiwo sesikhala senethiwekhi, ukuze kuguqulwe ukunyibilika kwayo. Ngenxa yokusabela kwamahhala kwe-OH phakathi kwe-aldehyde crosslinking agent kanye ne-cellulose ether, inani lama-molecular hydrophilic groups liyancishiswa, okuholela ekuncibilikeni okuncane kwamanzi komkhiqizo. Ngakho-ke, ngokulawula inani le-ejenti exhumanisayo, ukuphambanisa okumaphakathi kwe-cellulose ether kungabambezela isikhathi sokugeleza kwamanzi futhi kuvimbele umkhiqizo ekuncibilikeni ngokushesha esixazululweni esinamanzi, okuholela ekuhlanganiseni kwendawo.
Umthelela we-aldehyde crosslinking cellulose ether ngokuvamile uncike enanini le-aldehyde, i-pH, ukufana kokusabela okuhlanganayo, isikhathi sokuxhumanisa, kanye nezinga lokushisa. Izinga lokushisa eliphakeme kakhulu noma eliphansi kakhulu le-crosslinking kanye ne-pH kuzodala ukuphambana okungenakuhlehliswa ngenxa ye-hemiacetal ibe i-acetal, okuzoholela ku-cellulose ether engancibiliki ngokuphelele emanzini. Inani le-aldehyde kanye nokufana kokusabela okuxhumanisayo kuthinta ngokuqondile izinga lokuxhumanisa le-cellulose ether.
I-Formaldehyde ayisetshenziswa kancane ekuxhumaniseni i-cellulose ether ngenxa yobuthi bayo obuphezulu kanye nokuguquguquka okukhulu. Esikhathini esidlule, i-formaldehyde yayisetshenziswa kakhulu emkhakheni wezingubo zokugqoka, izinto zokunamathisela, izindwangu, futhi manje kancane kancane ithathelwa indawo ama-non-formaldehyde crosslinking agents anobuthi obuphansi. Umphumela wokuxhumanisa we-glutaraldehyde ungcono kunalowo we-glyoxal, kodwa unephunga elimnandi elinamandla, futhi intengo ye-glutaraldehyde iphakeme kakhulu. Ngokucatshangelwa okujwayelekile, embonini, i-glyoxal ivamise ukusetshenziselwa ukuxhumanisa i-ether ye-cellulose encibilikayo emanzini ukuze kuthuthukiswe ukunyibilika kwemikhiqizo. Ngokuvamile ekamelweni lokushisa, i-pH 5 ~ 7 izimo ze-asidi ezibuthakathaka zingenziwa ukusabela okuphambene. Ngemuva kokuxhumanisa, isikhathi sokugeleza kanye nesikhathi esiphelele se-hydration ye-cellulose ether sizoba side, futhi ukwenzeka kwe-agglomeration kuzoba buthaka. Uma kuqhathaniswa nemikhiqizo engeyona i-crosslinking, i-solubility ye-cellulose ether ingcono, futhi ngeke kube nemikhiqizo engancibilikisiwe esixazululweni, esivumelana nesicelo sezimboni. Lapho uZhang Shuangjian elungisa i-hydroxypropyl methyl cellulose, i-agent exhumanisa i-glyoxal yafafazwa ngaphambi kokuba yomiswe ukuze kutholwe i-hydroxypropyl methyl cellulose ngokuhlakazwa kwe-100%, engazange ibambe iqhaza lapho incibilika futhi yaba nokuhlakazeka okusheshayo nokuhlakazeka, okuxazulule ukunqwabelana ngokusebenza. isicelo futhi wanweba inkambu yesicelo.
Esimeni se-alkaline, inqubo ehlehliswayo yokwenza i-acetal izophulwa, isikhathi sokugeleza komkhiqizo sizofinyezwa, futhi izici zokuchithwa kwe-cellulose ether ngaphandle kokuxhumanisa zizobuyiselwa. Ngesikhathi sokulungiswa nokukhiqizwa kwe-cellulose ether, ukusabela okuhlanganayo kwe-aldehydes kuvame ukwenziwa ngemuva kwenqubo yokusabela kwe-etheration, kungaba esigabeni esiwuketshezi senqubo yokuwasha noma esigabeni esiqinile ngemuva kwe-centrifugation. Ngokujwayelekile, ohlelweni lokuwasha, ukufana kwe-crosslinking reaction kuhle, kodwa umphumela wokuphambana mubi. Kodwa-ke, ngenxa yemikhawulo yezinto zokusebenza zobunjiniyela, ukufana okuxhumanisayo esigabeni esiqinile kubi, kodwa umphumela wokuxhumanisa ungcono uma kuqhathaniswa nenani le-ejenti yokuxhumanisa elisetshenzisiwe lincane uma kuqhathaniswa.
Ama-aldehydes crosslinking agents aguqule i-ether cellulose encibilikayo emanzini, ngaphezu kokuthuthukisa ukunyibilika kwayo, kukhona nemibiko engasetshenziswa ukuthuthukisa izakhiwo zayo zemishini, ukuzinza kwe-viscosity nezinye izakhiwo. Isibonelo, u-Peng Zhang usebenzise i-glyoxal ukuphambana ne-HEC, futhi wahlola umthelela wokugxilisa i-ejenti exhumanisayo, i-pH exhumanisayo kanye nezinga lokushisa elixhumanisayo kumandla amanzi we-HEC. Imiphumela ibonisa ukuthi ngaphansi kwesimo esifanele sokuphambana, amandla amanzi e-HEC fiber ngemva kokuphambana akhuphuka ngo-41.5%, futhi ukusebenza kwawo kuthuthukiswa kakhulu. U-Zhang Jin usebenzise i-phenolic resin encibilika emanzini, i-glutaraldehyde ne-trichloroacetaldehyde ukuze i-CMC ixhumane. Ngokuqhathanisa izakhiwo, ikhambi le-CMC ye-phenolic resin encibilikayo encibilikayo yayinokuncipha okuncane kwe-viscosity ngemuva kokwelashwa kokushisa okuphezulu, okungukuthi, ukumelana nokushisa okungcono kakhulu.
2.2 I-Carboxylic acid crosslinking agents
I-Carboxylic acid crosslinking agents ibhekisela kuzinhlanganisela ze-polycarboxylic acid, ikakhulukazi ezihlanganisa i-succinic acid, i-malic acid, i-tartaric acid, i-citric acid namanye ama-acid kanambambili noma ama-polycarboxylic. Ama-crosslinkers e-Carboxylic acid aqale ukusetshenziswa ekuxhumaniseni imicu yendwangu ukuze kuthuthukiswe ukushelela kwayo. Indlela yokuxhumanisa imi kanje: iqembu le-carboxyl lihlangana neqembu le-hydroxyl le-molecule ye-cellulose ukukhiqiza i-esterified crosslinked cellulose ether. UWelch noYang et al. babengabokuqala ukutadisha indlela yokuphambana ye-carboxylic acid crosslinkers. Inqubo yokuxhumanisa yaba kanje: ngaphansi kwezimo ezithile, amaqembu amabili aseduze e-carboxylic acid kuma-crosslinkers e-carboxylic acid aqale aphelelwa amanzi ukuze enze i-cyclic anhydride, futhi i-anhydride iphendule nge-OH kuma-molecule e-cellulose ukuze akhe i-ether ye-cellulose e-crosslink enesakhiwo sendawo yenethiwekhi.
I-Carboxylic acid crosslinking agents ngokuvamile isabela nge-cellulose ether equkethe okufakwe esikhundleni se-hydroxyl. Ngenxa yokuthi i-carboxylic acid crosslinking agents ayincibiliki emanzini futhi ayinabo ubuthi, iye yasetshenziswa kabanzi ekutadisheni izinkuni, isitashi, i-chitosan ne-cellulose eminyakeni yamuva nje.
Okuphuma kokunye nokunye ukuguqulwa kwe-polymer esterification crosslinking yemvelo, ukuze kuthuthukiswe ukusebenza kwenkambu yohlelo lwayo.
U-Hu Hanchang et al. isebenzise i-sodium hypophosphite catalyst ukuze yamukele ama-polycarboxylic acid amane anezinhlaka ezahlukene zamangqamuzana: I-Propane tricarboxylic acid (PCA), i-1,2,3, i-4-butane tetracarboxylic acid (BTCA), i-cis-CPTA, i-cis-CHHA (i-Cis-ChHA) isetshenzisiwe. ukuqeda izindwangu zikakotini. Imiphumela yabonisa ukuthi isakhiwo esiyindilinga se-polycarboxylic acid eqeda indwangu kakotini sinokusebenza okungcono kokululama kwe-crease. Ama-molecule e-Cyclic polycarboxylic acid anamandla okuxhumanisa ama-agent ngenxa yokuqina kwawo okukhulu kanye nomphumela ongcono wokuphambana kunama-molecule e-carboxylic acid ewuchungechunge.
Wang Jiwei et al. wasebenzisa i-asidi exubile ye-citric acid ne-acetic anhydride ukwenza i-esterification kanye nokuguqulwa kwe-crosslinking kwesitashi. Ngokuhlola izici zokulungiswa kwamanzi nokunamathisela obala, baphethe ngokuthi isitashi esine-esterified crosslinked sinokuzinza okungcono kweqhwa, ukucwebezela okuphansi okusobala kanye nokuzinza okungcono kwe-viscosity okushisayo kunesitashi.
Amaqembu e-Carboxylic acid angathuthukisa ukuncibilika kwawo, ukubola kwe-biodegradability kanye nezakhiwo zemishini ngemuva kokusabela kwe-esterification crosslinking ne-OH esebenzayo kuma-polymers ahlukahlukene, kanye nezinhlanganisela ze-carboxylic acid zinezakhiwo ezingenabuthi noma ezinobuthi obuphansi, ezinamathemba abanzi okuguqulwa kokuphambana kwamanzi- I-soluble cellulose ether ebangeni lokudla, ibanga lezemithi kanye nezinkambu zokugqoka.
2.3 I-epoxy compound crosslinking agent
I-epoxy crosslinking agent iqukethe amaqembu e-epoxy amabili noma ngaphezulu, noma izinhlanganisela ze-epoxy eziqukethe amaqembu asebenzayo asebenzayo. Ngaphansi kwesenzo sama-catalysts, amaqembu e-epoxy namaqembu asebenzayo asabela nge--OH kuma-organic compounds ukukhiqiza ama-macromolecules ngesakhiwo senethiwekhi. Ngakho-ke, ingasetshenziselwa ukuphambana kwe-cellulose ether.
I-viscosity kanye nezakhiwo zemishini ze-cellulose ether zingathuthukiswa nge-epoxy crosslinking. Ama-epoxide aqale asetshenziselwa ukwelapha imicu yendwangu futhi abonisa umphumela omuhle wokuqeda. Nokho, kunemibiko embalwa ngokuguqulwa okuxhumanisa okuphambanayo kwe-cellulose ether ngama-epoxides. U-Hu Cheng et al uthuthukise i-multifunctional epoxy compound crosslinker: EPTA, ethuthukise i-Engle emanzi yokululama yezindwangu zangempela zikasilika ukusuka ku-200º ngaphambi kokwelashwa ukuya ku-280º. Ngaphezu kwalokho, ukukhokhiswa okuhle kwe-crosslinker kwandisa kakhulu izinga lokudaya kanye nezinga lokumuncwa kwezindwangu zangempela zikasilika odayi be-asidi. I-epoxy compound crosslinking agent esetshenziswa u-Chen Xiaohui et al. : I-polyethylene glycol diglycidyl ether (PGDE) ixhunywe nge-gelatin. Ngemuva kokuxhumanisa, i-gelatin hydrogel inokusebenza okuhle kakhulu kokululama okunwebekayo, ngezinga eliphakeme kakhulu lokutakula elifinyelela ku-98.03%. Ngokusekelwe ezifundweni zokuguqulwa okuxhumanisa okuphambanayo kwama-polymers emvelo njengendwangu ne-gelatin ngama-oxide aphakathi ezincwadini, ukuguqulwa okuxhumanisa okuphambanayo kwe-cellulose ether nama-epoxide nakho kunethemba elithembisayo.
I-Epichlorohydrin (eyaziwa nangokuthi i-epichlorohydrin) iyi-ejenti yokuphambana evame ukusetshenziswa ekwelapheni izinto ze-polymer zemvelo eziqukethe -OH, -NH2 namanye amaqembu asebenzayo. Ngemuva kwe-epichlorohydrin crosslinking, i-viscosity, i-asidi ne-alkali ukumelana, ukumelana nokushisa, ukumelana nosawoti, ukumelana ne-shear kanye nezakhiwo zemishini yezinto ezibonakalayo zizothuthukiswa. Ngakho-ke, ukusetshenziswa kwe-epichlorohydrin ku-cellulose ether crosslinking kunokubaluleka okukhulu kocwaningo. Isibonelo, u-Su Maoyao wenze into ekhangayo kakhulu ngokusebenzisa i-epiclorohydrin crosslinked CMC. Uxoxisane ngomthelela wesakhiwo esibalulekile, izinga lokushintsha kanye nezinga lokuxhumanisa ezindaweni ze-adsorption, wathola ukuthi inani lokugcinwa kwamanzi (WRV) kanye nenani lokugcinwa kwe-brine (SRV) lomkhiqizo owenziwe cishe ngo-3% we-crosslinking agent lenyuke ngo-26. izikhathi nezikhathi eziyi-17, ngokulandelana. Lapho uDing Changguang et al. kulungiswe i-viscous carboxymethyl cellulose, i-epichlorohydrin yengezwe ngemuva kwe-etherification yokuphambana. Uma kuqhathaniswa, i-viscosity yomkhiqizo oxhumene ifinyelele ku-51% ephakeme kunaleyo yomkhiqizo ongaxhumekile.
2.4 I-boric acid crosslinking agents
I-boric crosslinking agents ikakhulukazi ihlanganisa i-boric acid, i-borax, i-borate, i-organoborate namanye ama-agent aqukethe i-borate-containing crosslinking. Indlela yokuxhumanisa ngokuvamile kukholakala ukuthi i-boric acid (H3BO3) noma i-borate (B4O72-) yakha i-tetrahydroxy borate ion (B(OH)4-) esixazululweni, bese ikhipha amanzi ngo- -Oh kunhlanganisela. Yakha inhlanganisela ehlanganisiwe enesakhiwo senethiwekhi.
Ama-crosslinkers e-boric acid asetshenziswa kabanzi njengezinsiza kwezokwelapha, ingilazi, izitsha zobumba, i-petroleum neminye imikhakha. Amandla okusebenza wento ephathwa nge-boric acid crosslinking agent izothuthukiswa, futhi ingasetshenziselwa ukuphambana kwe-cellulose ether, ukuze kuthuthukiswe ukusebenza kwayo.
Ngawo-1960s, i-boron ye-inorganic (i-borax, i-boric acid ne-sodium tetraborate, njll.) kwakuyi-ejenti exhumanisayo eyinhloko eyayisetshenziswa ekuthuthukisweni koketshezi olusekelwe emanzini lokuqhekeka kwezizinda zikawoyela negesi. I-Borax kwakuyi-ejenti yokuqala yokuxhumanisa eyasetshenziswa. Ngenxa yokushiyeka kwe-boron ye-inorganic, njengesikhathi esifushane sokuxhumanisa kanye nokumelana nezinga lokushisa eliphansi, ukuthuthukiswa kwe-organoboron crosslinking agent sekuphenduke indawo yocwaningo. Ucwaningo lwe-organoboron lwaqala ngawo-1990. Ngenxa yezici zayo zokumelana nokushisa okuphezulu, i-glue kulula ukuyiphula, i-contactable delayed crosslinking, njll., i-organoboron izuze umphumela omuhle wokufaka isicelo ku-oyela ne-gas field fracturing. U-Liu Ji et al. yakha i-agent ye-polymer crosslinking equkethe iqembu le-phenylboric acid, i-crosslinking agent exutshwe ne-acrylic acid ne-polyol polymer ene-succinimide ester group reaction, ingcina ye-biological ewumphumela inokusebenza okuhle kakhulu okubanzi, ingabonisa ukunamathela okuhle kanye nezakhiwo zemishini endaweni enomswakama, futhi ingaba ukunamathela okulula kakhudlwana. Yang Yang et al. yakhiqiza i-zirconium boron crosslinking agent ekwazi ukumelana nokushisa okuphezulu, eyayisetshenziselwa ukunqamula i-guanidine gel base fluid of fracturing fluid, futhi yathuthukisa kakhulu izinga lokushisa nokumelana kwe-shear koketshezi oluphukayo ngemva kokwelashwa okuxhumanisa ukuphambana. Ukuguqulwa kwe-carboxymethyl cellulose ether nge-agent ye-boric acid crosslinking ku-petroleum drilling fluid kuye kwabikwa. Ngenxa yesakhiwo sayo esikhethekile, ingasetshenziswa emithi nasekwakheni
I-crosslinking ye-cellulose ether ekwakheni, ekuhlanganiseni nakweminye imikhakha.
2.5 I-Phosphide crosslinking agent
I-Phosphates crosslinking agents ikakhulukazi ihlanganisa i-phosphorus trichloroxy (phosphoacyl chloride), i-sodium trimetaphosphate, i-sodium tripolyphosphate, njll. Indlela yokuxhumanisa ukuthi ibhondi ye-PO noma ibhondi ye-P-Cl iqiniswa ne-molecular -OH kusisombululo samanzi ukuze kukhiqizwe i-diphosphate, yakhe isakhiwo senethiwekhi. .
I-Phosphide crosslinking ejenti ngenxa yobuthi obungenabo ubuthi noma obuphansi, esetshenziswa kakhulu ekudleni, ukuguqulwa kwe-polymer yento ye-polymer yemithi, njengesitashi, i-chitosan nokunye ukwelashwa kwe-polymer yemvelo ye-crosslinking. Imiphumela ibonisa ukuthi i-gelatinization kanye nezindawo zokuvuvukala zesitashi zingashintshwa kakhulu ngokungeza inani elincane le-phosphide crosslinking agent. Ngemuva kwe-starch crosslinking, izinga lokushisa le-gelatinization liyakhula, ukuzinza kwe-paste kuyathuthuka, ukumelana ne-asidi kungcono kunesitashi sokuqala, futhi amandla efilimu ayanda.
Kukhona futhi izifundo eziningi zokuphambana kwe-chitosan ne-ejenti ye-phosphide crosslinking, engathuthukisa amandla ayo okusebenza, ukuqina kwamakhemikhali nezinye izakhiwo. Okwamanje, ayikho imibiko ngokusetshenziswa kwe-ejenti ye-phosphide crosslinking yokwelashwa kwe-cellulose ether crosslinking. Ngenxa yokuthi i-cellulose ether nesitashi, i-chitosan namanye ama-polymers emvelo aqukethe -OH esebenzayo kakhulu, futhi i-phosphide crosslinking agent inezakhiwo ze-physiological ezingenabo ubuthi noma ezinobuthi obuphansi, ukusetshenziswa kwayo ocwaningweni lwe-cellulose ether crosslinking nakho kunamathuba angaba khona. Njenge-CMC esetshenziswa ekudleni, inkambu yebanga lokuxubha amazinyo enokuguqulwa kwe-ejenti ye-phosphide crosslinking, ingathuthukisa ukuqina kwayo, izakhiwo ze-rheological. I-MC, i-HPMC kanye ne-HEC esetshenziswa emkhakheni wezokwelapha ingathuthukiswa yi-ejenti ye-phosphide crosslinking.
2.6 Amanye ama-agent axhumanisayo
Ama-aldehyde angenhla, ama-epoxides kanye ne-cellulose ether crosslinking ayingxenye ye-etherification crosslinking, i-carboxylic acid, i-boric acid kanye ne-phosphide crosslinking agent ayingxenye ye-esterification crosslinking. Ukwengeza, ama-crosslinking agents asetshenziselwa i-cellulose ether crosslinking ahlanganisa inhlanganisela ye-isocyanate, i-nitrogen hydroxymethyl compounds, i-sulfhydryl compounds, i-metal crosslinking agents, i-organosilicon crosslinking agents, njll. Izici ezivamile zesakhiwo sayo samangqamuzana ukuthi i-molecule iqukethe amaqembu amaningi asebenzayo ahlanganisa kulula ukusabela ngokuthi -OH, futhi ingakha isakhiwo senethiwekhi esinezinhlangothi eziningi ngemva kokuxhumanisa. Izakhiwo zemikhiqizo ye-crosslinking zihlobene nohlobo lwe-ejenti exhumanisayo, i-crosslinking degree kanye nezimo zokuxhumanisa.
Ibhedi · Pabin · Condu et al. wasebenzisa i-toluene disocyanate (TDI) ukuphambanisa i-methyl cellulose. Ngemuva kokuxhumanisa, izinga lokushisa lokushintsha kwengilazi (Tg) liyenyuka ngokunyuka kwephesenti le-TDI, futhi ukuzinza kwesisombululo sayo samanzi kwaba ngcono. I-TDI iphinde isetshenziselwe ukuguqulwa kwe-crosslinking kuma-adhesives, ama-coatings nezinye izinkambu. Ngemuva kokuguqulwa, impahla yokunamathisela, ukumelana nokushisa kanye nokumelana kwamanzi kwefilimu kuzothuthukiswa. Ngakho-ke, i-TDI ingathuthukisa ukusebenza kwe-cellulose ether esetshenziswa ekwakhiweni, embozweni nasekunamathelweni ngokuguqulwa kwe-crosslinking.
Ubuchwepheshe be-disulfide crosslinking busetshenziswa kakhulu ekuguqulweni kwezinto zokwelapha futhi bunevelu ethile yocwaningo yokuphambana kwemikhiqizo ye-cellulose ether emkhakheni wezokwelapha. Shujun et al. kuhlanganiswe i-β-cyclodextrin nama-silica microspheres, i-chitosan exhunywe nge-mercaptoylated ne-glucan ngokusebenzisa ungqimba lwegobolondo le-gradient, futhi kukhishwe ama-silica microspheres ukuze kutholwe ama-nanocapses ahlanganisiwe e-disulfide, abonise ukuzinza okuhle ekulingiseni kwe-pH yemvelo.
Ama-metal crosslinking agents ikakhulukazi ama-inorganic and organic compounds ama-ion ensimbi aphezulu njenge-Zr(IV), i-Al(III), i-Ti(IV), i-Cr(III) ne-Fe(III). Ama-ion ensimbi aphezulu enziwa i-polymerized ukuze akhe ama-ion ebhuloho le-hydroxyl elinezinyuzi eziningi ngokusebenzisa i-hydration, i-hydrolysis ne-hydroxyl bridge. Ngokuvamile kunenkolelo yokuthi ukuxhumanisa ama-ion ensimbi ane-valence ephezulu ikakhulukazi ngama-ion ahlanganisa ama-nucleated hydroxyl bridging, okulula ukuwahlanganisa namaqembu e-carboxylic acid ukuze akhe ama-polymers esakhiwo esinezinhlangothi eziningi. Xu Kai et al. ufunde izici ze-rheological ze-Zr(IV), i-Al(III), Ti(IV), i-Cr(III) kanye ne-Fe(III) yochungechunge lwensimbi enenani eliphakeme le-carboxymethyl hydroxypropyl cellulose (CMHPC) kanye nokuzinza okushisayo, ukulahleka kokuhlunga. , umthamo wesihlabathi omisiwe, izinsalela eziphuka iglue kanye nokuhambisana nosawoti ngemva kokufakwa. Imiphumela yabonisa ukuthi, I-crosslinker yensimbi inezakhiwo ezidingekayo ku-ejenti yokufaka uwoyela yoketshezi oluqhekeka kahle kawoyela.

3. Ukuthuthukiswa kokusebenza kanye nokuthuthukiswa kobuchwepheshe be-cellulose ether ngokuhlanganisa ukuguqulwa

3.1 Ukupenda nokwakha
I-Cellulose ether ikakhulukazi i-HEC, i-HPMC, i-HEMC ne-MC isetshenziswa kakhulu emkhakheni wokwakha, ukunamathela, lolu hlobo lwe-cellulose ether kumele lube nokuphikiswa kahle kwamanzi, ukuqina, ukumelana nosawoti kanye nezinga lokushisa, ukumelana ne-shear, evame ukusetshenziswa odakeni lukasimende, upende we-latex. , i-ceramic tile adhesive, ipende yangaphandle yodonga, i-lacquer nokunye. Ngenxa yesakhiwo, izidingo zensimu yokuhlanganisa izinto kufanele zibe namandla okuhle kwemishini nokuzinza, ngokuvamile khetha i-etherification uhlobo lwe-crosslinking ejenti ku-cellulose ether crosslinking ukuguqulwa, njengokusetshenziswa kwe-epoxy halogenated alkane, i-boric acid crosslinking ejenti yokuphambana kwayo, ingathuthukisa umkhiqizo. i-viscosity, ukumelana nosawoti kanye nokushisa, ukumelana ne-shear kanye nezakhiwo zemishini.
3.2 Izinkambu zemithi, zokudla kanye namakhemikhali ansuku zonke
I-MC, i-HPMC kanye ne-CMC ku-ether ye-cellulose encibilikayo emanzini kuvame ukusetshenziswa ezintweni zokumboza ezenza imithi, izithasiselo ezikhishwa kancane kwezemithi kanye nokuqina kwemithi okuwuketshezi kanye nokuqiniswa kwe-emulsion. I-CMC ingasetshenziswa futhi njenge-emulsifier kanye ne-thickener ku-yogurt, imikhiqizo yobisi kanye nomuthi wokuxubha. I-HEC ne-MC zisetshenziswa emkhakheni wamakhemikhali wansuku zonke ukuze ushube, uhlakaze futhi u-homogenize. Ngenxa yokuthi insimu yezokwelapha, ukudla kanye nebanga lansuku zonke lamakhemikhali idinga izinto eziphephile nezingezona ubuthi, ngakho-ke, kulolu hlobo lwe-ether ye-cellulose ingasetshenziswa i-phosphoric acid, i-carboxylic acid crosslinking agent, i-sulfhydryl crosslinking agent, njll., ngemva kokuguqulwa kwe-crosslinking. thuthukisa i-viscosity yomkhiqizo, ukuzinza kwezinto eziphilayo kanye nezinye izakhiwo.
I-HEC ayivamisile ukusetshenziswa emkhakheni wezokwelapha nokudla, kodwa ngenxa yokuthi i-HEC iyi-ether ye-cellulose engeyona i-ionic ene-solubility eqinile, inezinzuzo zayo eziyingqayizivele ngaphezu kwe-MC, HPMC kanye ne-CMC. Ngokuzayo, izoxhunywa ngama-agent aphephile futhi angenabuthi, azoba namandla amakhulu okuthuthuka emkhakheni wezokwelapha nokudla.
3.3 Izindawo zokumba nokukhiqiza uwoyela
I-CMC kanye ne-carboxylated cellulose ether zivame ukusetshenziswa njenge-ejenti yokwelapha udaka yokumba, i-ejenti yokulahlekelwa uketshezi, i-ejenti yokuqina okufanele isetshenziswe. Njenge-ether ye-cellulose engeyona i-ionic, i-HEC iphinde isetshenziswe kabanzi emkhakheni wokumba uwoyela ngenxa yomphumela wayo omuhle wokuqina, umthamo oqinile wokumisa isihlabathi nokuzinza, ukumelana nokushisa, okuqukethwe kukasawoti omningi, ukumelana nepayipi eliphansi, ukulahlekelwa okuncane koketshezi, irabha esheshayo. ukuphuka kanye nezinsalela eziphansi. Njengamanje, ucwaningo olwengeziwe luwukusetshenziswa kwe-boric acid crosslinking agents kanye ne-metal crosslinking agents ukuze kuguqulwe i-CMC esetshenziswa ensimini kawoyela, i-non-ionic cellulose ether crosslinking modification research ibika kancane, kodwa ukuguqulwa kwe-hydrophobic kwe-non-ionic cellulose ether, okubonisa okuphawulekayo. i-viscosity, izinga lokushisa nokumelana nosawoti kanye nokuzinza kwe-shear, ukuhlakazeka okuhle nokumelana ne-hydrolysis yezinto eziphilayo. Ngemva kokuba crosslinked by boric acid, metal, epoxide, epoxy halogenated alkanes kanye nezinye ejenti crosslinking, cellulose ether esetshenziswa uwoyela drilling kanye ukukhiqizwa kuye kwathuthukisa ukuqina kwayo, ukumelana nosawoti kanye lokushisa, ukuzinza nokunye, okuyinto enethuba elikhulu isicelo in the esizayo.
3.4 Ezinye Izinkambu
I-Cellulose ether ngenxa yokuqina, i-emulsification, ukwakhiwa kwefilimu, ukuvikelwa kwe-colloidal, ukugcinwa komswakama, ukunamathela, ukulwa nokuzwela kanye nezinye izakhiwo ezinhle kakhulu, ezisetshenziswa kabanzi, ngaphezu kwezinkambu ezingenhla, ezibuye zisetshenziswe ekwenzeni iphepha, i-ceramics, ukuphrinta izindwangu kanye nokudaya, ukusabela kwe-polymerization nezinye izinkambu. Ngokwezidingo zezakhiwo ezibonakalayo emikhakheni eyahlukene, ama-ejenti ahlukene axhumanisa angasetshenziselwa ukuguqulwa kwe-crosslinking ukuze kuhlangatshezwane nezidingo zohlelo lokusebenza. Ngokuvamile, i-crosslinked cellulose ether ingahlukaniswa ngezigaba ezimbili: i-etherified crosslinked cellulose ether kanye ne-esterified crosslinked cellulose ether. Ama-aldehyde, ama-epoxides nezinye izixhumi ezihlanganayo zisabela ngokuthi -Oh ku-cellulose ether ukwenza ibhondi ye-ether-oxygen (-O-), eyingxenye ye-etherification crosslinkers. I-Carboxylic acid, i-phosphide, i-boric acid namanye ama-ejenti axhumanisayo asabela nge-OH ku-cellulose ether ukwenza amabhondi e-ester, angawabenzeli be-esterification crosslinking. Iqembu le-carboxyl ku-CMC lihlangana ne -OH kumenzeli oxhumanisayo ukukhiqiza i-esterified crosslinked cellulose ether. Njengamanje, lumbalwa ucwaningo olumayelana nalolu hlobo lokuguqulwa kwe-crosslinking, futhi sisekhona isikhala sokuthuthukiswa esikhathini esizayo. Ngenxa yokuthi ukuzinza kwebhondi ye-ether kungcono kunaleyo yebhondi ye-ester, uhlobo lwe-ether crosslinked cellulose ether lunokuqina okuqinile nezici zokusebenza. Ngokwezinkambu ezihlukene zohlelo lokusebenza, i-ejenti efanele yokuxhumanisa ingakhethelwa ukuguqulwa kwe-cellulose ether crosslinking, ukuze kutholwe imikhiqizo ehlangabezana nezidingo zohlelo lokusebenza.

4. Isiphetho

Njengamanje, imboni isebenzisa i-glyoxal ukuze i-crosslink cellulose ether, ukuze kubambezeleke isikhathi sokuqedwa, ukuxazulula inkinga ye-caking yomkhiqizo ngesikhathi sokuqedwa. I-Glyoxal crosslinked cellulose ether ingashintsha kuphela ukuncibilika kwayo, kodwa ayinakho ukuthuthukiswa okusobala kwezinye izakhiwo. Njengamanje, ukusetshenziswa kwamanye ama-agent axhumanisayo ngaphandle kwe-glyoxal ye-cellulose ether crosslinking akuvamile kufundwa. Ngenxa yokuthi i-cellulose ether isetshenziswa kakhulu ekubholeni uwoyela, ukwakha, ukumboza, ukudla, imithi kanye nezinye izimboni, ukuncibilika kwayo, i-rheology, izakhiwo zemishini zidlala indima ebalulekile ekusetshenzisweni kwayo. Ngokuguqulwa kwe-crosslinking, ingathuthukisa ukusebenza kwayo kwesicelo emikhakheni ehlukahlukene, ukuze ihlangabezane nezidingo zohlelo lokusebenza. Isibonelo, i-carboxylic acid, i-phosphoric acid, i-agent ye-boric acid crosslinking ye-cellulose ether esterification ingathuthukisa ukusebenza kwayo kwesicelo emkhakheni wokudla nemithi. Kodwa-ke, ama-aldehyde awakwazi ukusetshenziswa embonini yokudla nemithi ngenxa yobuthi bawo bokuphila. I-boric acid ne-metal crosslinking agents ziyasiza ekuthuthukiseni ukusebenza kukawoyela negesi uketshezi oluqhekekayo ngemva kokuhlanganisa i-cellulose ether esetshenziswa ekubholeni uwoyela. Amanye ama-alkyl crosslinking agents, afana ne-epichlorohydrin, angathuthukisa i-viscosity, izakhiwo ze-rheological kanye nezakhiwo zemishini ze-cellulose ether. Ngokuthuthuka okuqhubekayo kwesayensi nobuchwepheshe, izidingo zezimboni ezihlukahlukene zezakhiwo ezibonakalayo zithuthuka njalo. Ukuze kuhlangatshezwane nezidingo zokusebenza ze-cellulose ether emikhakheni ehlukahlukene yohlelo lokusebenza, ucwaningo lwesikhathi esizayo mayelana ne-cellulose ether crosslinking lunethuba elibanzi lokuthuthuka.