Ama-admixtures adlala indima ebalulekile ekuthuthukiseni ukusebenza kwesakhiwo sodaka oluxutshwe okomile, kodwa ukwengezwa kodaka oluxutshwe okomile kwenza izindleko ezibonakalayo zemikhiqizo yodaka oluxutshwe okomile zibe phezulu kakhulu kunezodaka lwendabuko, oluhlanganisa ngaphezu kuka-40% izindleko zempahla odakeni oluxutshwe okomile.
Ngokusekelwe kulezi zizathu ezingenhla, leli phepha lihlaziya futhi liqhathanise izici ezithile eziyisisekelo zezingxube ezivame ukusetshenziswa, futhi kulesi sisekelo, lihlola ukusebenza kwemikhiqizo yodaka oluxutshwe okomile kusetshenziswa izixube.
1. I-ejenti yokugcina amanzi
I-ejenti egcina amanzi iyinhlanganisela eyinhloko yokuthuthukisa ukusebenza kokugcinwa kwamanzi kodaka oluxutshwe okomile, futhi ingenye yezixube ezibalulekile ukuze kutholwe izindleko zodaka oluxutshwe okomile.
1.1 I-cellulose ether
I-Cellulose ether yitemu elivamile lochungechunge lwemikhiqizo ekhiqizwa ukusabela kwe-alkali cellulose kanye ne-etherifying agent ngaphansi kwezimo ezithile.I-alkali cellulose ithathelwa indawo ama-etherifying ahlukene ukuze kutholwe ama-cellulose ether ahlukene.Ngokwezakhiwo ze-ionization zama-substituents, ama-cellulose ether angahlukaniswa abe izigaba ezimbili: i-ionic (njenge-carboxymethyl cellulose) kanye ne-non-ionic (njenge-methyl cellulose).Ngokohlobo lwe-substituent, i-cellulose ether ingahlukaniswa ibe i-monoether (efana ne-methyl cellulose) ne-ether exutshiwe (njenge-hydroxypropyl methyl cellulose).Ngokuvumelana ne-solubility ehlukene, ingahlukaniswa ibe inyibilika emanzini (njenge-hydroxyethyl cellulose) kanye ne-organic solvent-soluble (njenge-ethyl cellulose), njll. ihlukaniswe ngohlobo olusheshayo kanye nohlobo lokuchithwa olubambezelekile oluphathwayo.
Indlela yokusebenza ye-cellulose ether odakeni imi kanje:
(1) Ngemva kokuba i-cellulose ether esesimendeni isincibilikisiwe emanzini, ukusatshalaliswa okusebenzayo nokufana kwe-cementitious material ohlelweni kuyaqinisekiswa ngenxa yomsebenzi ongaphezulu, futhi i-cellulose ether, njenge-colloid evikelayo, "igoqa" okuqinile. izinhlayiya kanye Ungqimba lwefilimu yokugcoba kwakheka endaweni yalo yangaphandle, okwenza uhlelo lodaka luzinze, futhi luthuthukise ukugeleza kodaka ngesikhathi sokuxuba kanye nokushelela kokwakhiwa.
(2) Ngenxa yesakhiwo sawo samangqamuzana, isixazululo se-cellulose ether senza amanzi odaka angabi lula ukulahlekelwa, futhi kancane kancane siyawakhulula isikhathi eside, okwenza udaka lugcine amanzi kahle nokusebenza.
1.1.1 Ifomula yemolekyuli ye-methyl cellulose (MC) [C6H7O2(OH)3-h(OCH3)n]x
Ngemuva kokuthi ukotini ocolisisiwe ulashwe nge-alkali, i-cellulose ether ikhiqizwa ngochungechunge lokusabela nge-methane chloride njenge-etherification agent.Ngokuvamile, izinga lokushintsha lingu-1.6~2.0, futhi ukunyibilika nakho kuhlukile ngamazinga ahlukene okushintsha.Kungokwe-non-ionic cellulose ether.
(1) I-methylcellulose iyancibilika emanzini abandayo, futhi kuyoba nzima ukuyincibilika emanzini ashisayo.Isixazululo saso esinamanzi sizinzile kakhulu ebangeni le-pH=3~12.Inokuhambisana okuhle nesitashi, i-guar gum, njll. kanye nama-surfactants amaningi.Lapho izinga lokushisa lifinyelela izinga lokushisa le-gelation, i-gelation iyenzeka.
(2) Ukugcinwa kwamanzi kwe-methyl cellulose kuncike enanini layo elingeziwe, i-viscosity, ukucoleka kwezinhlayiyana nezinga lokuqedwa.Ngokuvamile, uma inani elingeziwe likhulu, ukucoleka kuncane, futhi i-viscosity inkulu, izinga lokugcinwa kwamanzi liphezulu.Phakathi kwazo, inani lokwengeza linomthelela omkhulu kakhulu ekugcinweni kwamanzi, futhi izinga le-viscosity alilingani ngokuqondile nezinga lokugcinwa kwamanzi.Izinga lokuhlakazeka lincike kakhulu ezingeni lokuguqulwa kwendawo yezinhlayiya ze-cellulose kanye nokucoleka kwezinhlayiyana.Phakathi kwama-cellulose ether angenhla, i-methyl cellulose ne-hydroxypropyl methyl cellulose anamazinga aphezulu okugcina amanzi.
(3) Ukushintsha kwezinga lokushisa kuzothinta kakhulu izinga lokugcinwa kwamanzi e-methyl cellulose.Ngokuvamile, lapho izinga lokushisa liphezulu, kuba kubi nakakhulu ukugcinwa kwamanzi.Uma izinga lokushisa lodaka lidlula i-40 ° C, ukugcinwa kwamanzi kwe-methyl cellulose kuzoncishiswa kakhulu, okuthinta kakhulu ukwakhiwa kodaka.
(4) I-Methyl cellulose inomthelela omkhulu ekwakhiweni nasekunamatheleni kodaka.Igama elithi “adhesion” lapha libhekisela emandleni okunamathela azwakala phakathi kwethuluzi lokufaka isicelo lesisebenzi kanye ne-substrate yodonga, okungukuthi, ukumelana ne-shear kodaka.I-adhesiveness iphakeme, ukumelana kwe-shear kodaka kukhulu, futhi amandla adingwa ngabasebenzi ngesikhathi sokusebenzisa nawo makhulu, futhi ukusebenza kokwakhiwa kodaka kumpofu.I-Methyl cellulose adhesion isezingeni elilinganiselwe emikhiqizweni ye-cellulose ether.
1.1.2 Ifomula yemolekyuli ye-hydroxypropyl methylcellulose (HPMC) ithi [C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3]n]x
IHydroxypropyl methylcellulose iwuhlobo lwe-cellulose okukhishwa kwayo nokusetshenziswa kwayo kukhule ngokushesha eminyakeni yamuva.I-ether engeyona i-ionic cellulose exutshwe ukotini ocolisisiwe ngemva kokwenziwa kwe-alkalization, kusetshenziswa i-propylene oxide ne-methyl chloride njenge-etherification agent, ngochungechunge lokusabela.Izinga lokushintsha ngokuvamile liyi-1.2 ~ 2.0.Izakhiwo zayo zihlukile ngenxa yezilinganiso ezihlukene zokuqukethwe kwe-methoxyl nokuqukethwe kwe-hydroxypropyl.
(1) IHydroxypropyl methylcellulose incibilika kalula emanzini abandayo, futhi izohlangabezana nobunzima ekuncibilikeni emanzini ashisayo.Kodwa izinga lokushisa layo le-gelation emanzini ashisayo liphakeme kakhulu kunalelo le-methyl cellulose.I-solubility emanzini abandayo nayo ithuthuke kakhulu uma iqhathaniswa ne-methyl cellulose.
(2) I-viscosity ye-hydroxypropyl methylcellulose ihlobene nesisindo sayo samangqamuzana, futhi uma sikhulu isisindo samangqamuzana, i-viscosity iphakama.Ukushisa nakho kuthinta i-viscosity yayo, njengoba izinga lokushisa likhuphuka, i-viscosity iyancipha.Kodwa-ke, i-viscosity yayo ephezulu inomphumela ophansi wokushisa kune-methyl cellulose.Isixazululo saso sizinzile uma sigcinwe ekamelweni lokushisa.
(3) Ukugcinwa kwamanzi kwe-hydroxypropyl methylcellulose kuncike enanini layo elingeziwe, i-viscosity, njll., futhi izinga layo lokugcinwa kwamanzi ngaphansi kwenani elifanayo lokwengezwa lingaphezulu kwele-methyl cellulose.
(4) I-Hydroxypropyl methylcellulose izinzile ku-asidi ne-alkali, futhi isisombululo sayo esinamanzi sizinzile kakhulu ebangeni le-pH = 2 ~ 12.I-Caustic soda namanzi e-lime anethonya elincane ekusebenzeni kwawo, kodwa i-alkali ingasheshisa ukuchithwa kwayo futhi ikhulise ukubukeka kwayo.IHydroxypropyl methylcellulose izinzile kusawoti ovamile, kodwa lapho ukuhlangana kwesixazululo sikasawoti kuphezulu, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ivame ukwanda.
(5) I-Hydroxypropyl methylcellulose ingaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini ukuze zenze isixazululo se-uniform kanye ne-viscosity ephakeme.Okufana ne-polyvinyl alcohol, isitashi ether, ushingamu wemifino, njll.
(6) I-Hydroxypropyl methylcellulose inokumelana ne-enzyme okungcono kune-methylcellulose, futhi isisombululo sayo mancane amathuba okuthi sonakaliswe ama-enzyme kune-methylcellulose.
(7) Ukunamathela kwe-hydroxypropyl methylcellulose ekwakhiweni kodaka kungaphezulu kwalokho kwe-methylcellulose.
1.1.3 I-Hydroxyethylcellulose (HEC)
Yenziwe ngokotini ocolisisiwe ophathwe nge-alkali, futhi isabela nge-ethylene oxide njenge-etherification ejenti lapho kukhona i-acetone.Izinga lokushintsha ngokuvamile liyi-1.5 ~ 2.0.Ine-hydrophilicity eqinile futhi kulula ukumunca umswakama.
(1) I-Hydroxyethyl cellulose iyancibilika emanzini abandayo, kodwa kunzima ukuyincibilika emanzini ashisayo.Isixazululo saso sizinzile ekushiseni okuphezulu ngaphandle kwe-gelling.Ingasetshenziswa isikhathi eside ngaphansi kokushisa okuphezulu odakeni, kodwa ukugcinwa kwayo kwamanzi kuphansi kunaleyo ye-methyl cellulose.
(2) I-Hydroxyethyl cellulose izinzile ku-asidi evamile kanye ne-alkali.I-alkali ingasheshisa ukuqedwa kwayo futhi ikhulise kancane i-viscosity yayo.Ukuhlakazeka kwayo emanzini kubi kakhulu kunaleyo ye-methyl cellulose ne-hydroxypropyl methyl cellulose..
(3) I-Hydroxyethyl cellulose inokusebenza okuhle kwe-anti-sag kudaka, kodwa inesikhathi eside sokuhlehlisa usimende.
1.1.4 I-Carboxymethylcellulose (CMC) [C6H7O2(OH)2och2COONA]n
I-ionic cellulose ether yenziwe ngemicu yemvelo (ukotini, njll.) ngemva kokwelashwa kwe-alkali, kusetshenziswa i-sodium monochloroacetate njenge-etherification agent, futhi yenze uchungechunge lwemithi yokwelapha.Izinga lokushintsha ngokuvamile lingu-0.4~1.4, futhi ukusebenza kwayo kuthintwa kakhulu izinga lokushintsha.
(1) I-Carboxymethyl cellulose ine-hygroscopic, futhi izoqukatha amanzi amaningi uma igcinwe ngaphansi kwezimo ezijwayelekile.
(2) Isixazululo samanzi se-Carboxymethyl cellulose ngeke sikhiqize ijeli, futhi i-viscosity izokwehla ngokunyuka kwezinga lokushisa.Lapho izinga lokushisa lidlula ku-50°C, i-viscosity ayinakubuyela emuva.
(3) Ukuzinza kwayo kuthinteka kakhulu i-pH.Ngokuvamile, ingasetshenziswa odakeni olusekelwe ku-gypsum, kodwa hhayi odakeni olusekelwe kusimende.Uma kune-alkaline kakhulu, ilahlekelwa yi-viscosity.
(4) Ukugcinwa kwayo kwamanzi kuphansi kakhulu kunaleyo ye-methyl cellulose.Inomphumela wokuhlehlisa odakeni olususelwa ku-gypsum futhi inciphisa amandla ayo.Nokho, intengo ye-carboxymethyl cellulose iphansi kakhulu kunaleyo ye-methyl cellulose.
Isikhathi sokuthumela: Mar-23-2023