Isiphumo sokutyeba kwei-cellulose etherkuxhomekeke kwi: inqanaba le-polymerization ye-cellulose ether, uxinano lwesisombululo, izinga lokucheba, ubushushu kunye nezinye iimeko. Ipropati ye-gelling yesisombululo ikhethekile kwi-alkyl cellulose kunye ne-derivatives zayo eziguquliweyo. Iipropati ze-gelation zinxulumene nenqanaba lokutshintshwa, uxinano lwesisombululo kunye nezongezo. Kwi-hydroxyalkyl modified derivatives, iipropati ze-gel zikwanxulumene nenqanaba lokuguqulwa kwe-hydroxyalkyl. Kwi-viscosity ephantsi ye-MC kunye ne-HPMC, isisombululo se-10%-15% sinokulungiswa, i-viscosity ephakathi ye-MC kunye ne-HPMC zinokulungiswa isisombululo se-5%-10%, kwaye i-viscosity ephezulu ye-MC kunye ne-HPMC zinokulungiselela isisombululo se-2%-3% kuphela, kwaye ngesiqhelo udidi lwe-viscosity ye-cellulose ether lukwahlelwa ngesisombululo se-1%-2%.
I-cellulose ether ene-molecular-weight ephezulu inokusebenza kakuhle kokutyeba, kwaye ii-polymers ezine-molecular weights ezahlukeneyo zine-viscosities ezahlukeneyo kwisisombululo esifanayo soxinzelelo. I-viscosity ekujoliswe kuyo inokufezekiswa kuphela ngokongeza inani elikhulu le-cellulose ether ene-molecular weight ephantsi. I-viscosity yayo ayixhomekekanga kakhulu kwisantya sokucheba, kwaye i-viscosity ephezulu ifikelela kwi-viscosity ekujoliswe kuyo, ifuna ukongeza okuncinci, kwaye i-viscosity ixhomekeke ekusebenzeni kakuhle kokutyeba. Ke ngoko, ukuze kufezekiswe ukuhambelana okuthile, inani elithile le-cellulose ether (uxinzelelo lwesisombululo) kunye ne-viscosity yesisombululo kufuneka kuqinisekiswe. Ubushushu be-gel yesisombululo buyancipha ngokuthe ngqo ngokunyuka koxinzelelo lwesisombululo, kunye nee-gels kubushushu begumbi emva kokufikelela kuxinzelelo oluthile. I-gelling concentration ye-HPMC iphezulu kakhulu kubushushu begumbi.
Ukuvumelana kungalungiswa ngokukhetha ubungakanani besuntswana kunye nokukhetha ii-cellulose ethers ezinamaqondo ahlukeneyo okuguqulwa. Oku kubizwa ngokuba kukuguqulwa kukungenisa inqanaba elithile lokutshintshwa kwamaqela e-hydroxyalkyl kwisakhiwo sesikele se-MC. Ngokutshintsha amaxabiso okutshintshwa okunxulumeneyo kwamaqela amabini atshintshayo, oko kukuthi, amaxabiso okutshintshwa okunxulumeneyo kwe-DS kunye ne-MS kwamaqela e-methoxy kunye ne-hydroxyalkyl esihlala siwathetha. Iimfuno ezahlukeneyo zokusebenza kwe-cellulose ether zinokufunyanwa ngokutshintsha amaxabiso okutshintshwa okunxulumeneyo kwamaqela amabini atshintshayo.
Isisombululo samanzi se-cellulose ether esine-viscosity ephezulu sine-thixotropy ephezulu, nto leyo ekwaluphawu oluphambili lwe-cellulose ether. Izisombululo zamanzi ze-MC polymers zihlala zine-pseudoplastic kunye ne-non-thixotropic fluidity ngaphantsi kobushushu bazo be-gel, kodwa iipropati ze-Newtonian flow kwizinga eliphantsi lokucheba. I-Pseudoplasticity iyanda ngobunzima be-molecular okanye uxinzelelo lwe-cellulose ether, nokuba loluphi uhlobo lwe-substituent kunye nenqanaba lokutshintshwa. Ke ngoko, ii-cellulose ethers ze-viscosity grade efanayo, nokuba yi-MC, HPMC, HEMC, ziya kuhlala zibonisa iipropati ezifanayo ze-rheological logama nje uxinzelelo kunye nobushushu zigcinwa zingaguquki. Ii-gels zesakhiwo zenziwa xa ubushushu buphakanyisiwe, kwaye kwenzeka ukuhamba kwe-thixotropic ephezulu. Ii-ethers ze-cellulose ezine-viscosity ephezulu kunye ne-viscosity ephantsi zibonisa i-thixotropy nangaphantsi kobushushu be-gel. Le propati iluncedo kakhulu ekulungiseni i-leveling kunye ne-wegging ekwakheni i-building mortar.
Kufuneka kuchazwe apha ukuba kokukhona i-viscosity ephezului-cellulose ether, kokukhona ukugcinwa kwamanzi kubhetele, kodwa okukhona i-viscosity iphezulu, kokukhona ubunzima be-molecular ye-cellulose ether buphezulu, kunye nokuncipha kokunyibilika kwayo okuhambelanayo, okunefuthe elibi kuxinzelelo lwe-mortar kunye nokusebenza kokwakhiwa. Okukhona i-viscosity iphezulu, kokukhona isiphumo sokutyeba sibonakala ngakumbi kwi-mortar, kodwa asilingani ngokupheleleyo. I-viscosity ephakathi nephantsi, kodwa i-modified cellulose ether inokusebenza ngcono ekuphuculeni amandla olwakhiwo lwe-mortar emanzi. Ngokunyuka kwe-viscosity, ukugcinwa kwamanzi kwe-cellulose ether kuyaphucuka.
Ixesha leposi: Epreli-28-2024