I-Cellulose yi-polysaccharide eyenza iindidi ze-ethers ezinyibilikayo emanzini. I-cellulose thickeners zi-polymers ezingenayo i-nonionic emanzini. Imbali yokusetyenziswa kwayo inde kakhulu, ingaphezulu kweminyaka engama-30, kwaye kukho iindidi ezininzi. Zisasetyenziswa phantse kuzo zonke iipeyinti zelatex kwaye zezona ziphambili kwii-thickeners. I-Cellulosic thickeners zisebenza kakhulu kwiinkqubo ezinamanzi kuba ziyajiya ngokwazo. Kwishishini lepeyinti, ezona zityebi zisetyenziswa ngokuqhelekileyo zezi: i-methyl cellulose (MC), i-hydroxyethyl cellulose (HEC), i-ethyl hydroxyethyl cellulose (EHEC), i-hydroxypropyl cellulose (HPC), i-hydroxypropyl methyl cellulose (HPMC) kunye ne-hydrophobically modified hydroxyethyl cellulose. HMHEC). I-HEC yipolysaccharide enyibilikayo emanzini esetyenziswa kakhulu ekujikeni kwepeyinti ye-matt kunye ne-semi-gloss ye-latex yokwakha. I-Thickeners ifumaneka kumabakala ahlukeneyo e-viscosity kunye ne-thickeners kunye nale cellulose inombala obalaseleyo wokuhambelana kunye nokuzinza kokugcina.
Umgangatho, i-anti-splash, i-film-forming kunye ne-anti-sagging ye-coating film ixhomekeke kwi-molecular weight ye-HEC. I-HEC kunye nezinye iipolymers ezingadityaniswanga namanzi anyibilikayo zityebisa isigaba samanzi sokugquma. I-cellulose thickeners ingasetyenziswa yodwa okanye idityaniswe nezinye i-thickeners ukufumana i-rheology ekhethekileyo. I-cellulose ethers ingaba nemilinganiselo eyahlukeneyo yeemolekyuli kunye namabanga ahlukeneyo e-viscosity, ukusuka kubunzima obuphantsi be-molecular 2% isisombululo se-aqueous kunye ne-viscosity malunga ne-10 MPS ukuya kwi-viscosity ephezulu ye-molecular weight ye-100 000 MP.S. Amanqanaba asezantsi obunzima bemolekyuli aqhele ukusetyenziswa njengeecolloids ezikhuselayo kwi-latex paint emulsion polymerization, kwaye uninzi lwamabanga aqhelekileyo (viscosity 4 800–50 000 MP·S) asetyenziswa njengezinto ezityebisayo. Indlela yolu hlobo lwe-thickener ibangelwa ukunyuswa okuphezulu kweebhondi ze-hydrogen kunye ne-entanglement phakathi kwamakhonkco ayo e-molecular.
Iselulosi yesiNtu yipolima enobunzima obuphezulu bemolekyuli ethi ijiye ngakumbi ngokubophelela phakathi kwamatyathanga emolekyuli. Ngenxa ye-viscosity ephezulu kwizinga eliphantsi le-shear, ipropati yokulinganisa ihlwempu, kwaye ichaphazela i-gloss yefilimu yokugqoka. Kwizinga eliphezulu le-shear, i-viscosity iphantsi, ukuchasana kwe-splash yefilimu yokugqoka ihlwempu, kwaye ukugcwala kwefilimu yokugubungela akulungile. Iimpawu zokusetyenziswa kwe-HEC, ezifana nokuchasana kwebrashi, ukufowunelwa kunye ne-roller spatter, zihambelana ngokuthe ngqo nokukhethwa kwe-thickener. Kwakhona iipropathi zayo zokuhamba ezifana nokulinganisa kunye nokumelana ne-sag zichatshazelwa kakhulu ngama-thickeners.
I-cellulose eguqulelwe nge-Hydrophobically modified (HMHEC) yi-cellulose thickener enokuguqulwa kwe-hydrophobic kwamanye amatyathanga e-branched (amaqela amaninzi e-alkyl e-long-chain angeniswa ecaleni kwekhonkco eliphambili lesakhiwo). Le ngubo ine-viscosity ephezulu kwizinga eliphezulu lokucheba kwaye ngoko ke ukubunjwa kwefilimu engcono. Ezinje ngeNatrosol Plus Grade 330, 331, Cellosize SG-100, Bermocoll EHM-100. Ukuqina kwayo kuthelekiseka naleyo ye-cellulose ether thickeners enobunzima obukhulu bemolekyuli. Iphucula i-viscosity kunye nomgangatho we-ICI, kwaye inciphisa ukuxinana komhlaba. Ngokomzekelo, ukuxhatshazwa kwe-HEC malunga ne-67 MN / m, kunye noxinzelelo lwe-HMHEC yi-55 ~ 65 MN / m.
I-HMHEC inokutshiza okugqwesileyo, i-anti-sagging, iipropati zokulinganisa, iglosi elungileyo kunye ne-anti-pigment caking. Isetyenziswa ngokubanzi kwaye ayinayo impembelelo embi ekubunjweni kwefilimu yeepeyinti ze-latex ze-particle size. Ukusebenza kakuhle kwefilimu kunye nokusebenza okuchasene nokubola. Le nto i-asociative thickener isebenza ngcono kunye ne-vinyl acetate copolymer systems, kwaye ukusebenza kwayo kufana nezinye i-thickeners associative, kodwa kunye neendlela ezilula.
Ixesha lokuposa: Mar-16-2023