Igama lesiTshayina le-HPMC yi-hydroxypropyl methylcellulose. Ayina-ionic kwaye isoloko isetyenziswa njengesixhobo sokugcina amanzi kudaka oluxutyiweyo. Yeyona nto isetyenziswa ngokuqhelekileyo ukugcina amanzi kwidaka.
Inkqubo yemveliso ye-HPMC yimveliso ye-ether esekwe kwi-polysaccharide eveliswa yi-alkalization kunye ne-etherification ye-cotton fiber (yasekhaya). Ayinayo intlawulo ngokwayo, ayiphenduli nge-ion ehlawulisiweyo kwizinto eziphathekayo ze-gelling, kwaye inomsebenzi ozinzile. Ixabiso liphantsi kunezinye iintlobo ze-cellulose ethers, ngoko ke isetyenziswa ngokubanzi kwi-dry-mixed mortar.
Umsebenzi we-hydroxypropyl methylcellulose: Iyakwazi ukujiyisa udaka oluxutywe ngokutsha ukuze lube ne-viscosity ethile emanzi kwaye ithintele ulwahlulo. (Thickening) Ukugcinwa kwamanzi kukwayeyona nto ibaluleke kakhulu, enceda ukugcina ubuninzi bamanzi akhululekile kumdaka, ukwenzela ukuba emva kokuba udaka lwakhiwe, izinto ze-cementitious zinexesha elingakumbi lokukhupha amanzi. (Ukugcinwa kwamanzi) Ineempawu zokungenisa umoya, ezinokuzisa amaqamza afanayo kunye nelungileyo ukuphucula ukwakhiwa kodaka.
Okukhona iphezulu i-viscosity ye-hydroxypropyl methylcellulose ether, kokukhona ukugcinwa kwamanzi kube ngcono. I-Viscosity yiparameter ebalulekileyo yokusebenza kwe-HPMC. Okwangoku, abavelisi abahlukeneyo be-HPMC basebenzisa iindlela ezahlukeneyo kunye nezixhobo zokulinganisa i-viscosity ye-HPMC. Iindlela eziphambili ziHaakeRotovisko, Hoppler, Ubbelohde kunye neBrookfield.
Kwimveliso efanayo, iziphumo ze-viscosity ezilinganiswa ngeendlela ezahlukeneyo zahluke kakhulu, kwaye ezinye zide ziphindwe kabini. Ngoko ke, xa kuthelekiswa ne-viscosity, kufuneka iqhutywe phakathi kweendlela zokuvavanya okufanayo, kubandakanywa ukushisa, i-rotor, njl. Ngokuphathelele ubungakanani be-particle, i-fineral particle, ingcono ukugcinwa kwamanzi. Emva kokuba amasuntswana amakhulu e-cellulose ether adibane namanzi, umphezulu uyanyibilika ngokukhawuleza kwaye wenze ijeli ukusonga izinto zokuthintela iimolekyuli zamanzi ukuba zingaqhubeki nokungena. Ngamanye amaxesha ayinakuchithwa ngokulinganayo kwaye inyibilikiswe nasemva kwexesha elide, ukwenza isisombululo esinamafu okanye i-agglomeration. Ichaphazela kakhulu ukugcinwa kwamanzi kwe-cellulose ether, kwaye ukunyibilika yenye yezinto zokukhetha i-cellulose ether.
Ukulunga kukwayisalathisi sokusebenza esibalulekileyo se-methyl cellulose ether. I-MC esetyenziselwa udaka lwepowder eyomileyo iyadingeka ukuba ibe ngumgubo, kunye nomxholo wamanzi aphantsi, kunye nokulungiswa kwakhona kufuna i-20% ~ 60% ye-particle size ibe ngaphantsi kwe-63um. Ukucoleka kuchaphazela ukunyibilika kwe-hydroxypropyl methylcellulose ether. I-coarse MC idla ngokuba yigranular, kwaye kulula ukuyinyibilika emanzini ngaphandle kwe-agglomeration, kodwa izinga lokuchithwa licotha kakhulu, ngoko ke ayifanelekanga ukusetyenziswa kwidaka elomileyo lomgubo.
Kwipowder eyomileyo yodaka, i-MC ihlakazekile phakathi kwezinto zesamente ezifana ne-aggregate, i-fine filler kunye nesamente, kwaye kuphela umgubo ococekileyo owaneleyo unokunqanda i-methyl cellulose ether agglomeration xa ixutywa namanzi. Xa i-MC yongezwa ngamanzi ukunyibilikisa i-agglomerates, kunzima kakhulu ukuchithwa kunye nokuchithwa. I-coarse fineness ye-MC ayiyonkcitho nje kuphela, kodwa ikwanciphisa amandla asekuhlaleni odaka. Xa udaka olunjalo olomileyo lusetyenziswa kwindawo enkulu, isantya sokunyanga sodaka lwendawo eyomileyo siya kuncitshiswa kakhulu, kwaye iintanda ziya kubonakala ngenxa yamaxesha ahlukeneyo okuphilisa. Ngodaka olutshiziweyo kunye nokwakhiwa komatshini, imfuno yokucolisa iphezulu ngenxa yexesha elifutshane lokuxuba. Ngokuqhelekileyo, okukhona i-viscosity iphezulu, ngcono isiphumo sokugcina amanzi. Nangona kunjalo, ukuphakama kwe-viscosity kunye nokuphakama kwe-molecular weight ye-MC, ukuhla okuhambelanayo kwi-solubility yayo kuya kuba nefuthe elibi kumandla kunye nokusebenza kokwakhiwa kodaka.
Ukuphakama kwe-viscosity, kubonakala ngakumbi impembelelo yokuqina kumdaka, kodwa ayilingani ngokuthe ngqo. Ukuphakama kwe-viscosity, i-viscous ngakumbi i-mortar emanzi iya kuba, oko kukuthi, ngexesha lokwakha, kubonakaliswa njengokunamathela kwi-scraper kunye nokunamathela okuphezulu kwi-substrate. Kodwa akuncedi ukunyusa amandla esakhiwo sodaka olumanzi ngokwalo. Oko kukuthi, ngexesha lokwakha, ukusebenza kwe-anti-sag akubonakali. Ngokuchasene noko, i-viscosity ethile ephakathi kunye nephantsi kodwa i-methyl cellulose ethers elungisiweyo inomsebenzi ogqwesileyo ekuphuculeni amandla okwakhiwa kodaka olumanzi.
Ukugcinwa kwamanzi kwe-HPMC kukwanxulumene nobushushu obusetyenzisiweyo, kwaye ukugcinwa kwamanzi kwe-methyl cellulose ether kuncipha ngokunyuka kwamaqondo obushushu. Nangona kunjalo, kwizinto ezisetyenziswayo, udaka olomileyo lomgubo luhlala lusetyenziswa kwiindawo ezishushu kumaqondo obushushu aphezulu (angaphezulu kwama-40 degrees) kwiindawo ezininzi, ezinje ngodonga lwangaphandle lokutyatyekwa phantsi kwelanga ehlotyeni, oluhlala lukhawulezisa Ukunyangwa kwesamente kunye nokuqina kwesamente. udaka olomileyo lomgubo. Ukwehla kwezinga lokugcinwa kwamanzi kukhokelela kwimvakalelo ecacileyo yokuba zombini ukusebenza kunye nokumelana nokuqhekeka kuchaphazeleka, kwaye kubaluleke kakhulu ukunciphisa impembelelo yobushushu phantsi kwesi simo.
Ngokubhekiselele koku, izongezo ze-methyl hydroxyethyl cellulose ether okwangoku zithathwa njengeziphambili kuphuhliso lobuchwepheshe. Nangona isixa se-methyl hydroxyethyl cellulose sandisiwe (ifomula yasehlotyeni), ukusebenza kunye nokumelana nokuqhekeka kusenganakho ukuhlangabezana neemfuno zokusetyenziswa. Ngonyango oluthile olukhethekileyo kwi-MC, olufana nokwandisa iqondo le-etherification, njl., isiphumo sokugcinwa kwamanzi sinokugcinwa kwiqondo lokushisa eliphezulu, ukwenzela ukuba linike ukusebenza okungcono phantsi kweemeko ezinzima.
I-dosage ye-HPMC ayifanele ibe phezulu kakhulu, ngaphandle koko iya kwandisa imfuno yamanzi yodaka, iya kubambelela kwi-trowel, kwaye ixesha lokumisela liya kuba lide kakhulu, eliya kuchaphazela ukwakhiwa. Iimveliso zodaka ezahlukeneyo zisebenzisa HPMC kunye viscosities ezahlukeneyo, kwaye musa ukusebenzisa high-viscosity HPMC nje. Ke ngoko, nangona iimveliso ze-hydroxypropyl methylcellulose zilungile, ziyaqhwatyelwa izandla xa zisetyenziswa kakuhle. Ukukhetha i-HPMC efanelekileyo luxanduva oluphambili lwabasebenzi baselabhoratri yeshishini. Okwangoku, abathengisi abaninzi abanganyanisekanga badibanisa i-HPMC, kwaye umgangatho usezantsi kakhulu. Xa ukhetha i-cellulose ethile, ilabhoratri kufuneka yenze umsebenzi omhle kuvavanyo lokuqinisekisa ukuzinza kwemveliso yodaka, kwaye unganyolukeli ngexabiso eliphantsi kwaye ubangele ilahleko engeyomfuneko.
Ixesha lokuposa: Dec-16-2022