1 Isingeniso
I-adhesive yethayela esekelwe kusimende njengamanje iyindlela enkulu kakhulu yokusebenzisa udaka oluxutshwe nowomile, olwakhiwe ngosimende njengento eyinhloko yokuqinisa futhi lunezelwa yi-aggregates esezingeni, izinto zokugcina amanzi, izinto zokuqinisa zakuqala, i-latex powder kanye nezinye izingxube zezithako eziphilayo noma ezingaphili. Ngokuvamile, idinga ukuhlanganiswa namanzi kuphela uma isetshenziswa. Uma iqhathaniswa nodaka oluvamile lwesimende, ingathuthukisa kakhulu amandla okubopha phakathi kwezinto ezibhekene ne-substrate, futhi inokumelana okuhle kokushelela kanye nokumelana okuhle kwamanzi namanzi. Isetshenziswa kakhulu ukunamathisela izinto zokuhlobisa ezifana namathayela odonga angaphakathi nangaphandle okwakha, amathayela odonga, njll. Isetshenziswa kabanzi ezindongeni zangaphakathi nangaphandle, phansi, ezindlini zangasese, emakhishini nakwezinye izindawo zokuhlobisa izakhiwo. Njengamanje iyinto yokubopha ithayela esetshenziswa kakhulu.
Ngokuvamile uma sahlulela ukusebenza kwe-adhesive yethayela, asigcini nje ngokunaka ukusebenza kwayo kanye nekhono lokulwa nokushelela, kodwa futhi sinaka namandla ayo okusebenza kanye nesikhathi sokuvula. I-Cellulose ether eku-adhesive yethayela ayithinti nje kuphela izakhiwo ze-rheological ze-adhesive ye-porcelain, njengokusebenza okubushelelezi, ummese wokunamathela, njll., kodwa futhi inethonya elinamandla ezimpahleni ze-adhesive yethayela.
2. Umthelela esikhathini sokuvulwa kwe-adhesive yethayela
Uma i-rubber powder kanye ne-cellulose ether zikhona ndawonye ku-wet mortar, amanye amamodeli edatha abonisa ukuthi i-rubber powder inamandla amakhulu oku-kinetic okunamathela emikhiqizweni ye-cement hydration, kanti i-cellulose ether ikhona kakhulu ku-interstitial fluid, okuthinta i-Mortar viscosity kanye nesikhathi sokusetha. Ukuqina kobuso be-cellulose ether kuphakeme kunokwe-rubber powder, futhi ukucebisa i-cellulose ether eningi ku-mortar interface kuzoba wusizo ekwakhekeni kwezibopho ze-hydrogen phakathi kobuso besisekelo kanye ne-cellulose ether.
Ku-mortar emanzi, amanzi ku-mortar ayahwamuka, bese i-cellulose ether icebile ebusweni, bese kwakheka ifilimu ebusweni be-mortar zingakapheli imizuzu emi-5, okuzonciphisa izinga lokuhwamuka okulandelayo, njengoba amanzi amaningi esuswa ku-mortar ejiyile. Ingxenye yayo ithuthela kungqimba lwe-mortar oluncane, bese ifilimu eyakhiwe ekuqaleni incibilika kancane, futhi ukufuduka kwamanzi kuzoletha ukucebisa i-cellulose ether ebusweni be-mortar.
Ngakho-ke, ukwakheka kwefilimu ye-cellulose ether ebusweni be-mortar kunethonya elikhulu ekusebenzeni kwe-mortar. 1) Ifilimu eyakhiwe incane kakhulu futhi izoncibilika kabili, okungenakukwazi ukunciphisa ukuhwamuka kwamanzi futhi kunciphise amandla. 2) Ifilimu eyakhiwe ikhulu kakhulu, ukuhlushwa kwe-cellulose ether ku-mortar interstitial liquid kuphezulu, futhi i-viscosity iphezulu, ngakho akulula ukuphula ifilimu engaphezulu lapho amathayili enamathiselwe. Kungabonakala ukuthi izakhiwo zokwakha ifilimu ze-cellulose ether zinomthelela omkhulu esikhathini sokuvula. Uhlobo lwe-cellulose ether (HPMC, HEMC, MC, njll.) kanye nezinga le-etherification (izinga lokufaka esikhundleni) kuthinta ngqo izakhiwo zokwakha ifilimu ze-cellulose ether, kanye nobunzima nokuqina kwefilimu.
3. Ithonya emandleni okudweba
Ngaphezu kokunikeza lezi zakhiwo eziwusizo ezishiwo ngenhla ku-mortar, i-cellulose ether iphinda ilibazise i-hydration kinetics ye-samente. Lo mphumela wokubambezela ubangelwa kakhulu ukumuncwa kwama-molecule e-cellulose ether ezigabeni ezahlukene zamaminerali ohlelweni lwe-samente olufakwa amanzi, kodwa ngokuvamile, ukuvumelana ukuthi ama-molecule e-cellulose ether afakwa emanzini njenge-CSH kanye ne-calcium hydroxide. Emikhiqizweni yamakhemikhali, akuvamile ukumuncwa esigabeni sokuqala samaminerali se-clinker. Ngaphezu kwalokho, i-cellulose ether inciphisa ukuhamba kwama-ion (Ca2+, SO42-, …) esixazululweni se-pore ngenxa yokwanda kwe-viscosity yesisombululo se-pore, ngaleyo ndlela kubambezeleke inqubo yokumuncwa kwamanzi.
Ukuqina kungenye ipharamitha ebalulekile, emelela izici zamakhemikhali ze-cellulose ether. Njengoba kushiwo ngenhla, ukuqina kuthinta kakhulu amandla okugcina amanzi futhi kunomthelela omkhulu ekusebenzeni kahle kwe-mortar entsha. Kodwa-ke, izifundo zokuhlola zithole ukuthi ukuqina kwe-cellulose ether cishe akunawo umthelela ku-kinetics ye-hydration yesamente. Isisindo sama-molecular asinawo umthelela omncane ku-hydration, futhi umehluko omkhulu phakathi kwezisindo zama-molecular ezahlukene yimizuzu eyi-10 kuphela. Ngakho-ke, isisindo sama-molecular akuyona ipharamitha ebalulekile yokulawula ukuqina kwesamente.
Ukuhlehliswa kwe-cellulose ether kuncike esakhiweni sayo samakhemikhali, futhi umkhuba ojwayelekile uphethe ngokuthi, kwi-MHEC, uma izinga le-methylation liphakeme, umphumela wokuhlehliswa kwe-cellulose ether awunciphi. Ngaphezu kwalokho, umphumela wokuhlehliswa kwe-hydrophilic substitution (njengokufaka esikhundleni se-HEC) unamandla kunowokufaka esikhundleni se-hydrophobic (njengokufaka esikhundleni se-MH, i-MHEC, i-MHPC). Umphumela wokuhlehliswa kwe-cellulose ether uthintwa kakhulu yimingcele emibili, uhlobo kanye nobuningi bamaqembu angena esikhundleni.
Ukuhlolwa kwethu okuhlelekile kuphinde kwathola ukuthi okuqukethwe kwezinto ezithatha indawo kudlala indima ebalulekile emandleni okusebenza kwama-adhesive ethayili. Sihlole ukusebenza kwe-HPMC ngamazinga ahlukene okushintsha ama-adhesive ethayili, futhi sahlola umphumela wama-ether e-cellulose aqukethe amaqembu ahlukene ngaphansi kwezimo ezahlukene zokupholisa ku-Effects on mechanical properties of tile adhesives.
Esivivinyweni, sibheka i-HPMC, okuyi-ether ehlanganisiwe, ngakho-ke kufanele sihlanganise lezi zithombe ezimbili. Ku-HPMC, idinga izinga elithile lokumuncwa ukuqinisekisa ukuncibilika kwamanzi kanye nokudluliselwa kokukhanya. Siyazi okuqukethwe kwezinto ezithatha indawo. Iphinde inqume izinga lokushisa lejeli le-HPMC, eliphinde linqume indawo yokusetshenziswa kwe-HPMC. Ngale ndlela, okuqukethwe kweqembu le-HPMC okuvame ukusetshenziswa nakho kufakwe ngaphakathi kobubanzi. Kulolu bubanzi, indlela yokuhlanganisa i-methoxy ne-hydroxypropoxy Ukuze kufezwe umphumela omuhle kakhulu okuqukethwe ucwaningo lwethu. Isibalo 2 sibonisa ukuthi ngaphakathi kobubanzi obuthile, ukwanda kokuqukethwe kwamaqembu e-methoxyl kuzoholela ekuthambekeni kokwehla kwamandla okukhipha, kuyilapho ukwanda kokuqukethwe kwamaqembu e-hydroxypropoxyl kuzoholela ekwandeni kwamandla okukhipha. Kunomphumela ofanayo emahoreni okuvula.
Ukushintsha kwamandla omshini ngaphansi kwesimo sesikhathi esivulekile kuhambisana nalokho ngaphansi kwezimo zokushisa ezijwayelekile. I-HPMC enokuqukethwe okuphezulu kwe-methoxyl (DS) kanye nokuqukethwe okuphansi kwe-hydroxypropoxyl (MS) inokuqina okuhle kwefilimu, kodwa izothinta izakhiwo zokumanzisa izinto ezimanzi.
Isikhathi sokuthunyelwe: Jan-09-2023