Zothina za utoto wa latex ziyenera kukhala zogwirizana bwino ndi mankhwala a latex polymer, apo ayi padzakhala kapangidwe kakang'ono mu filimu yophimba, ndipo kusonkhana kwa tinthu tosasinthika kudzachitika, zomwe zimapangitsa kuti kukhuthala ndi kukula kwa tinthu tolimba kuchepe. Zothina zidzasintha mphamvu ya emulsion. Mwachitsanzo, zothina za cationic zidzakhala ndi zotsatira zosasinthika pa ma emulsifier anionic ndikuyambitsa demulsification. Chothina chabwino cha utoto wa latex chiyenera kukhala ndi zinthu zotsatirazi:
1. Mlingo wochepa komanso kukhuthala kwabwino
2. Kukhazikika bwino kwa malo osungira, sikuchepetsa kukhuthala chifukwa cha zochita za ma enzyme, ndipo sikuchepetsa kukhuthala chifukwa cha kusintha kwa kutentha ndi pH
3. Kusunga madzi bwino, palibe thovu loonekeratu la mpweya
4. Palibe zotsatirapo zoyipa pa utoto monga kukana kutsuka, kunyezimira, mphamvu yobisala komanso kukana madzi
5. Palibe kusuntha kwa utoto
Ukadaulo wokulitsa utoto wa latex ndi njira yofunika kwambiri yowonjezerera ubwino wa latex ndikuchepetsa ndalama. Hydroxyethyl cellulose ndi chinthu chabwino kwambiri chokulitsa utoto, chomwe chimagwira ntchito zambiri pakukulitsa, kukhazikika komanso kusintha kwa rheological kwa utoto wa latex.
Pakupanga utoto wa latex, hydroxyethyl cellulose (HEC) imagwiritsidwa ntchito ngati chosungunula, chokhuthala komanso chosungunula utoto kuti chikhazikitse kukhuthala kwa chinthucho, kuchepetsa kusakanikirana, kupangitsa utoto kukhala wosalala komanso wosalala, ndikupangitsa utoto wa latex kukhala wolimba. Rheology yabwino, imatha kupirira mphamvu zambiri zodula, ndipo imatha kupereka kulinganiza bwino, kukana kukanda komanso kufanana kwa utoto. Nthawi yomweyo, HEC imakhala yogwira ntchito bwino, ndipo utoto wa latex wokhuthala ndi HEC uli ndi pseudoplasticity, kotero kutsuka, kuzunguliza, kudzaza, kupopera ndi njira zina zomangira kuli ndi ubwino wopulumutsa ntchito, sikophweka kuchotsa, kutsika, komanso kupopera pang'ono. HEC ili ndi mtundu wabwino kwambiri. Ili ndi kusokonezeka kwabwino kwa mitundu yambiri ndi zomangira, zomwe zimapangitsa utoto wa latex kukhala ndi mtundu wabwino komanso wokhazikika. Kugwiritsa ntchito mosiyanasiyana mu kapangidwe kake, ndi ether yopanda ionic. Chifukwa chake, ingagwiritsidwe ntchito pa pH yochuluka (2 ~ 12), ndipo ingasakanizidwe ndi zinthu zina mu utoto wa latex monga ma pigment osinthika, zowonjezera, mchere wosungunuka kapena ma electrolyte.
Palibe vuto lililonse pa filimu yophimba, chifukwa yankho lamadzi la HEC lili ndi mawonekedwe omveka bwino a mphamvu ya pamwamba pa madzi, silivuta kutulutsa thovu panthawi yopanga ndi kumanga, ndipo chizolowezi cha mabowo amoto ndi mabowo ang'onoang'ono ndi chochepa.
Kusunga bwino. Pakusungidwa kwa nthawi yayitali, utoto umatha kusungunuka ndi kuyimitsidwa, ndipo palibe vuto la mtundu woyandama ndi kuphuka. Pamwamba pa utoto pali madzi ochepa, komanso kutentha kwa malo osungira kumasintha kwambiri. Kukhuthala kwake kumakhala kokhazikikabe.
HEC ikhoza kuwonjezera mtengo wa PVC (kuchuluka kwa pigment) mpaka 50-60%. Kuphatikiza apo, chokhuthala pamwamba cha utoto wochokera m'madzi chingagwiritsenso ntchito HEC.
Pakadali pano, zothina zomwe zimagwiritsidwa ntchito mu utoto wa latex wapakatikati ndi wapamwamba kwambiri ndi HEC ndi acrylic polymer zomwe zimatumizidwa kunja (kuphatikiza polyacrylate, homopolymer kapena copolymer emulsion thickeners za acrylic acid ndi methacrylic acid).
Hydroxyethyl cellulose ingagwiritsidwe ntchito pochiza matenda a shuga.
1. Monga guluu wothira madzi kapena woteteza
Kawirikawiri, HEC yokhala ndi kukhuthala kwa 10-30mPaS imagwiritsidwa ntchito. HEC yomwe ingagwiritsidwe ntchito mpaka 300mPa·S idzakhala ndi mphamvu yabwino yofalikira ngati igwiritsidwa ntchito limodzi ndi ma surfactants a anionic kapena cationic. Mlingo wofunikira nthawi zambiri umakhala 0.05% ya kulemera kwa monomer.
2. Monga chokhuthala
Gwiritsani ntchito 15000mPa. Mlingo wofunikira wa HEC yokhuthala kwambiri pamwamba pa s ndi 0.5-1% ya kulemera konse kwa utoto wa latex, ndipo mtengo wa PVC ukhoza kufika pafupifupi 60%. Gwiritsani ntchito HEC ya pafupifupi 20Pa,s mu utoto wa latex, ndipo magwiridwe antchito a utoto wa latex ndi abwino kwambiri. Mtengo wongogwiritsa ntchito HEC pamwamba pa 30O00Pa.s ndi wotsika. Komabe, mphamvu zoyezera za utoto wa latex sizoyenera. Poganizira zofunikira paubwino ndi kuchepetsa ndalama, ndi bwino kugwiritsa ntchito HEC yapakatikati ndi yapamwamba kwambiri pamodzi.
3. Njira yosakaniza utoto wa latex
HEC yokonzedwa pamwamba ikhoza kuwonjezeredwa mu ufa wouma kapena mu mawonekedwe a phala. Ufa woumawo umawonjezeredwa mwachindunji ku pigment grind. pH pamalo odyetsera ayenera kukhala 7 kapena kuchepera. Zigawo za alkaline monga Yanbian dispersant zitha kuwonjezeredwa HEC ikanyowa ndikufalikira kwathunthu. Ma slurry opangidwa ndi HEC ayenera kusakanizidwa mu slurry HEC isanakhale ndi nthawi yokwanira yonyowetsa ndikulola kuti ikhale yolimba mpaka itakula. Ndizothekanso kukonzekera HEC pulp ndi ethylene glycol coalescing agents.
4. Utoto wa latex wotsutsana ndi nkhungu
HEC yosungunuka m'madzi imawonongeka ikakhudzana ndi nkhungu zomwe zimakhala ndi zotsatira zapadera pa cellulose ndi zotumphukira zake. Sikokwanira kuwonjezera zosungira mu utoto wokha, zigawo zonse ziyenera kukhala zopanda ma enzyme. Chopangira utoto wa latex chiyenera kukhala choyera, ndipo zida zonse ziyenera kutsukidwa nthawi zonse ndi 0.5% formalin kapena O.1% mercury solution.
Nthawi yotumizira: Disembala-26-2022