I-cellulose ethers luhlobo lwe-organic polymer compounds eguqulwe ngokwekhemikhali ukusuka kwiselulosi yendalo. Ngokuqhelekileyo zisetyenziswa kwizinto zokwakha, ngakumbi kwizinto ezisekelwe kwisamente. Impembelelo ye-cellulose ether kwinkqubo ye-cement hydration ibonakaliswe ngokukodwa kule miba ilandelayo: ukuchithwa kweengqungquthela zesamente, ukugcinwa kwamanzi, umphumo wokuqina, kunye nefuthe kwi-morphology kunye nophuhliso lwamandla emveliso ye-cement hydration.
1. Intshayelelo kwi-cement hydration
Inkqubo ye-hydration yesamente luluhlu lweendlela ezintsonkothileyo zomzimba kunye neekhemikhali phakathi kwesamente namanzi. Ezi mpendulo zibangela ukuba i-cement paste ibe nzima kancinci ukwenza isakhiwo esiqinileyo, ekugqibeleni ivelise iimveliso ze-hydration ezifana ne-calcium silicate hydrate (CSH) kunye ne-calcium hydroxide (CH). Ngethuba le nkqubo, izinga le-hydration reaction rate ye-samente, i-fluidity kunye nokugcinwa kwamanzi kwi-slurry, kunye nokwakheka kweemveliso ze-hydration zichaphazela ngokuthe ngqo amandla kunye nokuqina kwekhonkrithi yokugqibela.
2. Indlela yokusebenza ye-cellulose ethers
I-ether ye-cellulose idlala indima ebalulekileyo yokulawula umzimba kunye neekhemikhali kwinkqubo ye-cement hydration. I-ether ye-cellulose ichaphazela kakhulu inkqubo ye-hydration ye-samente ngeendlela ezimbini: enye ngokuchaphazela ukusabalalisa kunye nokuphuma kwamanzi kwi-sement slurry; enye ngokuchaphazela ukusasazwa kunye nokudityaniswa kwamasuntswana esamente.
Ukulawula ukufuma kunye nokugcinwa kwamanzi
I-cellulose ethers inokuphucula kakhulu ukugcinwa kwamanzi kwizinto ezisekelwe kwi-samente. Ngenxa ye-hydrophilicity yayo eqinile, i-cellulose ether inokwenza isisombululo esizinzile se-colloidal emanzini, esinokufunxa kwaye sigcine umswakama. Lo mthamo wokubamba amanzi ubalulekile ekunciphiseni ukuqhekeka okubangelwa ukulahleka kwamanzi ngokukhawuleza kwikhonkrithi ngexesha lokugqithiswa kwangaphambili. Ngokukodwa kwiindawo ezomileyo okanye kwiimeko zokushisa okuphezulu, i-cellulose ether inokuthintela ngokufanelekileyo amanzi ukuba aphume ngokukhawuleza kwaye aqinisekise ukuba ubuninzi bamanzi kwi-sement slurry yanele ukuxhasa ukuphendulwa kwe-hydration eqhelekileyo.
Rheology kunye nokutyeba
I-cellulose ethers inokuphucula i-rheology ye-sement slurries. Emva kokongeza i-cellulose ether, ukuhambelana kwe-cement slurry kuya kwanda kakhulu. Le nto yenziwa ikakhulu kulwakhiwo lwetyathanga elide elenziwe ziimolekyuli ze-cellulose ether emanzini. Le molekyuli ende ende inokuthintela ukuhamba kweengqungquthela zesamente, ngaloo ndlela ikhulise i-viscosity kunye nokuhambelana kwe-slurry. Le propati ibaluleke kakhulu kwizicelo ezifana nokutyabeka kunye ne-adhesives ye-tile, njengoko ikhusela udaka lwesamente ukuba luhambe ngokukhawuleza ngelixa lubonelela ngokwenziwa komsebenzi ongcono wokwakha.
Libazisa ukufakwa kwamanzi kwaye ulungelelanise ixesha lokumisela
I-ether ye-cellulose inokulibazisa ukusabela kwe-hydration ye-samente kunye nokwandisa ukusetwa kokuqala kunye nexesha lokugqibela lokumisela le-sement slurry. Esi siphumo senzeka ngenxa yokuba iimolekyuli ze-cellulose ether zibhengezwa kumphezulu weengqungquthela zesamente, zenza umqobo othintela ukudibanisa ngokuthe ngqo phakathi kwamanzi kunye neengqungquthela zesamente, ngaloo ndlela unciphisa ukusabela kwe-hydration. Ngokulibazisa ixesha lokumisela, ii-ethers ze-cellulose zinokuphucula ukusebenza kolwakhiwo, zinike abasebenzi bokwakha ixesha elingakumbi lokwenza uhlengahlengiso nezilungiso.
3. Impembelelo kwifom yeemveliso zesamente ze-hydration
Ubukho be-cellulose ethers nabo buchaphazela i-microstructure yeemveliso ze-samente hydration. Uphononongo lubonise ukuba i-morphology ye-calcium silicate hydrate (CSH) gel iya kutshintsha emva kokongeza i-cellulose ether. Iimolekyuli ze-ether ze-cellulose zinokuchaphazela i-crystal structure ye-CSH, iyenze ikhululeke ngakumbi. Esi sakhiwo sikhululekile sinokunciphisa amandla okuqala ukuya kwinqanaba elithile, kodwa sikwanceda ukuphucula ukuqina kwezinto.
I-cellulose ethers nayo inokunciphisa ukubunjwa kwe-ettringite ngexesha lenkqubo yokuhambisa amanzi. Ekubeni i-cellulose ether ibuyisela umlinganiselo we-hydration reaction, izinga lokubunjwa kwe-ettringite kwi-samente liyancitshiswa, ngaloo ndlela linciphisa uxinzelelo lwangaphakathi olubangelwa ukwanda komthamo ngexesha lenkqubo yokunyanga.
4. Impembelelo kuphuhliso lwamandla
I-cellulose ethers nayo inempembelelo ebalulekileyo ekuphuhliseni amandla ezinto ezisekelwe kwi-samente. Ngenxa yokuba ii-ethers zeselulosi zilibazisa izinga lokugalela amanzi kwisamente, uphuhliso lwangoko lwamandla entlama yesamente ludla ngokucotha. Nangona kunjalo, njengoko i-hydration reaction iqhubeka, umphumo olawulayo we-cellulose ether ukugcinwa kwamanzi kunye ne-hydration product morphology inokuvela ngokuthe ngcembe, eya kunceda ukuphucula amandla kwinqanaba elilandelayo.
Kufuneka kuqatshelwe ukuba inani elongezelelweyo kunye nohlobo lwe-cellulose ether lunefuthe elibini kumandla. Umlinganiselo ofanelekileyo we-cellulose ether unokuphucula ukusebenza kokwakhiwa kunye nokwandisa amandla kamva, kodwa ukusetyenziswa ngokugqithiseleyo kunokukhokelela ekunciphiseni amandla okuqala ezinto ezisekelwe kwi-samente kwaye kuchaphazele iimpawu zokugqibela zomatshini. Ke ngoko, kwizicelo ezisebenzayo, uhlobo kunye nedosi ye-cellulose ether kufuneka iphuculwe kwaye iyilwe ngokweemfuno ezithile zobunjineli.
I-ether ye-cellulose ichaphazela inkqubo ye-hydration kunye neempawu eziphathekayo ze-samente ngokuphucula ukugcinwa kwamanzi kwizinto ezisekelwe kwi-samente, ukulungelelanisa umlinganiselo we-hydration, kunye nokuchaphazela uhlobo lweemveliso ze-hydration. Nangona i-cellulose ethers inokubangela ukulahleka kwamandla okuqala, inokuphucula ukuqina kunye nokuqina kwekhonkrithi kwixesha elide. Ukongezwa kwe-cellulose ether kunokuphucula kakhulu ukusebenza kokwakhiwa, ngokukodwa kwiimeko zesicelo ezifuna ixesha elide lokusebenza kunye neemfuno eziphezulu zokugcina amanzi. Ineenzuzo ezingenakubuyiselwa. Kwizicelo zangempela zobunjineli, ukhetho olufanelekileyo lohlobo kunye nedosi ye-cellulose ether inokulinganisela amandla, ukusebenza kokwakhiwa kunye neemfuno zokuqina kwezinto.
Ixesha lokuposa: Sep-27-2024