Thickener ndi wamba komanso wogwiritsidwa ntchito kwambiri pamadzi opangira madzi. Pambuyo kuwonjezera thickener, akhoza kuonjezera mamasukidwe akayendedwe ❖ kuyanika dongosolo, potero kuteteza ndi wandiweyani zinthu ❖ kuyanika kukhazikika. Sipadzakhala chodabwitsa chifukwa cha kukhuthala kwa utoto kukhala woonda kwambiri. Pali mitundu yambiri ya zinthu zonenepa, ndipo mitundu yosiyanasiyana yazinthu imakhala ndi mfundo zokulirapo zamakachitidwe osiyanasiyana opaka. Pali pafupifupi mitundu inayi ya zokhuthala wamba: polyurethane thickeners, acrylic thickeners, inorganic thickeners ndi thickeners kwa cellulose thickeners.
1. Makulidwe limagwirira a associative polyurethane thickener
Makhalidwe apangidwe a polyurethane associative thickeners ndi ma polima a lipophilic, hydrophilic ndi lipophilic tri-block, omwe ali ndi magulu otsiriza a lipophilic kumapeto onse awiri, kawirikawiri aliphatic hydrocarbon magulu, ndi gawo losungunuka la polyethylene glycol pakati. Malingana ngati pali kuchuluka kokwanira kwa thickener mu dongosolo, dongosolo lidzapanga dongosolo lonse la maukonde.
Mu dongosolo la madzi, pamene ndende ya thickener ndi yaikulu kuposa ndende yovuta ya micelle, magulu a lipophilic mapeto amalumikizana kuti apange micelles, ndipo thickener amapanga dongosolo la maukonde kudzera mu mgwirizano wa micelles kuonjezera kukhuthala kwa dongosolo.
Mu latex system, thickener sikungangopanga mgwirizano kudzera mu lipophilic terminal group micelles, koma chofunika kwambiri, gulu la lipophilic terminal la thickener limadsorbed pamtunda wa latex particle. Pamene magulu awiri a lipophilic mapeto adsorbed pamitundu yosiyanasiyana ya latex, ma molekyulu a thickener amapanga milatho pakati pa tinthu tating'onoting'ono.
2. thickening limagwirira wa polyacrylic asidi alkali kutupa thickener
Polyacrylic asidi alkali kutupa thickener ndi mtanda zogwirizana copolymer emulsion, ndi copolymer alipo mu mawonekedwe a asidi ndi tinthu tating'ono kwambiri, maonekedwe ndi yamkaka woyera, mamasukidwe akayendedwe ndi otsika, ndipo ali bata wabwino pa otsika pH kugonana, ndi insoluble. mmadzi. Pamene mankhwala a alkaline awonjezeredwa, amasandulika kukhala obalalika omveka bwino komanso otupa kwambiri.
The thickening zotsatira za polyacrylic asidi alkali kutupa thickener amapangidwa ndi neutralizing gulu carboxylic asidi ndi hydroxide; pamene wothandizila alkali anawonjezera, gulu carboxylic asidi kuti si mosavuta ionized nthawi yomweyo n'kukhala ionized ammonium carboxylate kapena zitsulo Mu mawonekedwe mchere, ndi electrostatic repulsion zotsatira kwaiye pamodzi anion likulu la copolymer macromolecular unyolo, kotero kuti mtanda. -unyolo wolumikizidwa wa copolymer macromolecular amakula ndikufalikira mwachangu. Chifukwa cha kusungunuka kwa m'deralo ndi kutupa, tinthu tating'onoting'ono timachulukitsidwa nthawi zambiri ndipo kukhuthala kumawonjezeka kwambiri. Popeza kuti crosslinks sangathe kusungunuka, copolymer mu mawonekedwe a mchere akhoza kuonedwa ngati copolymer dispersion amene particles kukula kwambiri.
Ma polyacrylic acid thickeners amakhala ndi kukhuthala kwabwino, kuthamanga kwachangu, komanso kukhazikika kwachilengedwe, koma amakhudzidwa ndi pH, kusakanizika kwa madzi, komanso kutsika kowala.
3. Makulidwe limagwirira a organic thickeners
Inorganic thickeners makamaka monga kusinthidwa bentonite, attapulgite, etc. Inorganic thickeners ndi ubwino thickening amphamvu, wabwino thixotropy, lonse pH osiyanasiyana, ndi wabwino bata. Komabe, popeza bentonite ndi ufa wosawerengeka wokhala ndi kuyamwa kwabwino kwa kuwala, ukhoza kuchepetsa kwambiri kuwala kwa filimu yophimba ndikuchita ngati wothandizira. Chifukwa chake, mukamagwiritsa ntchito bentonite mu utoto wonyezimira wa latex, chisamaliro chiyenera kuperekedwa pakuwongolera mlingo. Nanotechnology yazindikira kukula kwa tinthu tating'onoting'ono, komanso yapatsanso zinthu zina zatsopano zopangira ma inorganic thickeners.
Kukhuthala kwa ma inorganic thickeners ndizovuta. Nthawi zambiri amakhulupirira kuti kunyansidwa pakati pa milandu yamkati kumawonjezera kukhuthala kwa utoto. Chifukwa cha kusayenda bwino kwake, zimakhudza kuwala ndi kuwonekera kwa filimu ya utoto. Nthawi zambiri amagwiritsidwa ntchito ngati primer kapena utoto wapamwamba kwambiri.
4. Makulidwe limagwirira a cellulose thickener
Ma cellulose thickeners ali ndi mbiri yakale yachitukuko ndipo amagwiritsidwanso ntchito kwambiri. Malinga ndi mapangidwe awo a maselo, amagawidwa kukhala hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxymethyl cellulose, carboxymethyl cellulose, ndi zina zotero, zomwe zimagwiritsidwa ntchito kwambiri hydroxyethyl cellulose (HEC).
The thickening limagwirira wa mapadi thickener makamaka ntchito hydrophobic unyolo waukulu pa dongosolo lake kupanga hydrogen zomangira ndi madzi, ndipo nthawi yomweyo kucheza ndi magulu ena polar pa kapangidwe ake kumanga atatu azithunzithunzi maukonde dongosolo ndi kuonjezera rheological voliyumu. wa polima. , kuletsa kusuntha kwaulele kwa polima, potero kumawonjezera kukhuthala kwa zokutira. Pamene mphamvu yakumeta ubweya ikugwiritsidwa ntchito, mawonekedwe a maukonde atatu-dimensional akuwonongeka, zomangira za haidrojeni pakati pa mamolekyu zimatha, ndipo kukhuthala kumachepa. Pamene mphamvu ya shear imachotsedwa, zomangira za haidrojeni zimapangidwanso, ndipo mawonekedwe a maukonde atatu-dimensional amakhazikitsidwanso, potero kuonetsetsa kuti chophimbacho chikhoza kukhala ndi katundu wabwino. rheological katundu.
Ma cellullosic thickeners ali olemera m'magulu a hydroxyl ndi magawo a hydrophobic pamapangidwe awo. Amakhala ndi kukhuthala kwakukulu ndipo samakhudzidwa ndi pH. Komabe, chifukwa cha kusakanizika kwawo kwa madzi komanso kukhudza kuyika kwa filimu ya utoto, ndizosavuta Kukhudzidwa ndi kuwonongeka kwa tizilombo toyambitsa matenda ndi zofooka zina, zopangira ma cellulose zimagwiritsidwa ntchito makamaka pakukulitsa utoto wa latex.
Pokonzekera zokutira, kusankha kwa thickener kuyenera kuganizira mozama zinthu zambiri, monga kuyenderana ndi dongosolo, kukhuthala, kukhazikika kosungirako, ntchito yomanga, mtengo ndi zina. Zokhuthala zingapo zitha kuphatikizidwa ndikugwiritsidwa ntchito kuti ziwonetsetse ubwino wa chokhuthala chilichonse, ndikuwongolera mtengo wake malinga ndi magwiridwe antchito okhutiritsa.
Nthawi yotumiza: Mar-02-2023