Cellulose ndi polysaccharide yomwe imapanga ma ether osiyanasiyana osungunuka m'madzi. Ma cellulose thickeners ndi ma polima osasungunuka m'madzi a nonionic. Mbiri yakugwiritsa ntchito kwake ndi yayitali kwambiri, yopitilira zaka 30, ndipo pali mitundu yambiri. Amagwiritsidwabe ntchito pafupifupi pafupifupi utoto wonse wa latex ndipo ndizomwe zimakhala zonenepa kwambiri. Ma cellulosic thickeners ndi othandiza kwambiri pamakina amadzimadzi chifukwa amalimbitsa madzi okha. M'makampani opaka utoto, zokhuthala zomwe zimagwiritsidwa ntchito kwambiri ndi: methyl cellulose (MC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC) ndi hydrophobically modified hydroxyethyl cellulose. HMHEC). HEC ndi polysaccharide yosungunuka m'madzi yomwe imagwiritsidwa ntchito kwambiri pakukulitsa utoto wa latex wa matt ndi semi-gloss. Ma thickeners amapezeka m'makalasi osiyanasiyana a viscosity ndi thickeners omwe ali ndi cellulose ali ndi mtundu wabwino kwambiri wogwirizana komanso kusunga bata.
Mawonekedwe, anti-splash, film-forming and anti-sagging katundu wa filimu yokutira zimadalira kulemera kwa molekyulu ya HEC. HEC ndi ma polima ena osalumikizana ndi madzi osungunuka amakulitsa gawo lamadzi la zokutira. Ma cellulose thickeners amatha kugwiritsidwa ntchito okha kapena kuphatikiza ndi zokhuthala zina kuti apeze rheology yapadera. Ma cellulose ethers amatha kukhala ndi zolemetsa zosiyanasiyana zama cell ndi magiredi osiyanasiyana a viscosity, kuyambira kulemera kwa maselo otsika 2% njira yamadzimadzi yokhala ndi mamasukidwe amtundu wa 10 MPS kupita kumtunda wapamwamba wama cell kulemera kwa 100 000 MP.S. Low maselo kulemera magiredi zambiri ntchito ngati zoteteza colloids mu latex utoto emulsion polymerization, ndi magiredi ambiri (makamakamakamakamakamakamakalidwe 4 800-50 000 MP·S) ntchito monga thickeners. Limagwirira a mtundu wa thickener ndi chifukwa mkulu hydration wa hydrogen zomangira ndi entanglement pakati unyolo wake maselo.
Ma cellulose achikhalidwe ndi polima wolemera kwambiri wa mamolekyulu omwe amakhuthala makamaka kudzera m'mipata yapakati pa unyolo wa maselo. Chifukwa cha kukhuthala kwapamwamba pamtunda wochepa wa shear, katundu woyezera ndi wosauka, ndipo zimakhudza kuwala kwa filimu yophimba. Pakumeta ubweya wambiri, ma viscosity ndi otsika, kukana kwa splash kwa filimu yokutira kumakhala koyipa, ndipo kudzaza kwa filimu yophimba sikwabwino. Makhalidwe ogwiritsira ntchito HEC, monga kukana burashi, kujambula kujambula ndi spatter yodzigudubuza, amagwirizana mwachindunji ndi kusankha kwa thickener. Komanso mawonekedwe ake oyenda monga kusanja ndi kukana kwa sag amakhudzidwa kwambiri ndi zonenepa.
Hydrophobically modified cellulose (HMHEC) ndi cellulose thickener yomwe imakhala ndi kusintha kwa hydrophobic pa maunyolo ena a nthambi (magulu angapo a alkyl aatali amalowetsedwa pamodzi ndi unyolo waukulu wa mapangidwe). Chophimba ichi chimakhala ndi mamasukidwe apamwamba kwambiri pamitengo yometa ubweya wambiri motero mapangidwe abwino amakanema. Monga Natrosol Plus Grade 330, 331, Cellosize SG-100, Bermocoll EHM-100. Kukhuthala kwake kumafanana ndi ma cellulose ether thickeners okhala ndi ma cell okulirapo. Imawongolera kukhuthala komanso kukhazikika kwa ICI, komanso imachepetsa kupsinjika kwapamwamba. Mwachitsanzo, kuthamanga kwapamtunda kwa HEC kuli pafupifupi 67 MN/m, ndipo kuthamanga kwapamtunda kwa HMHEC ndi 55 ~ 65 MN/m.
HMHEC ili ndi sprayability yabwino kwambiri, anti-sagging, katundu wosanjikiza, gloss wabwino komanso anti-pigment cake. Amagwiritsidwa ntchito kwambiri ndipo alibe zotsatira zoipa pa filimu mapangidwe zabwino tinthu kukula latex utoto. Kuchita bwino kopanga mafilimu komanso kuchitapo kanthu kwa anti-corrosion. Izi zowonjezera zowonjezera zimagwira ntchito bwino ndi makina a vinyl acetate copolymer, ndipo machitidwe ake ndi ofanana ndi ena ophatikizana, koma ndi zosavuta.
Nthawi yotumiza: Mar-16-2023