Kukhazikitsa kwa cellulose thickener

Latex utoto ndi chisakanizo cha inki, filler dispersions ndi polima dispersions, ndi zina ayenera kugwiritsidwa ntchito kusintha mamasukidwe akayendedwe ake kuti akhale ndi rheological katundu zofunika pa gawo lililonse kupanga, kusunga ndi kumanga. Zowonjezera zotere nthawi zambiri zimatchedwa thickeners, zomwe zimatha kuwonjezera kukhuthala kwa zokutira ndikusintha mawonekedwe a rheological of zokutira, motero amatchedwanso ma rheological thickeners.

Zotsatirazi zimangowonetsa mikhalidwe yayikulu yamafuta a cellulose omwe amagwiritsidwa ntchito kwambiri ndikugwiritsa ntchito utoto wa latex.

Zipangizo zama cellulose zomwe zitha kugwiritsidwa ntchito pakupaka zikuphatikizapo methyl cellulose, hydroxyethyl cellulose, ndi hydroxypropyl methyl cellulose. Chinthu chachikulu cha cellulose thickener ndi chakuti makulidwe ake ndi odabwitsa, ndipo amatha kupatsa utoto mphamvu yosungira madzi, yomwe imatha kuchedwetsa nthawi yowuma ya utoto pamlingo winawake, komanso kupanga utoto kukhala ndi thixotropy, kuletsa utoto kuti usaume. Mvula ndi stratification panthawi yosungirako, komabe, zokometsera zoterezi zimakhalanso ndi vuto la kusanja bwino kwa utoto, makamaka pogwiritsa ntchito magiredi apamwamba kwambiri.

Ma cellulose ndi michere yazachilengedwe, chifukwa chake njira zothana ndi mildew ziyenera kulimbikitsidwa mukazigwiritsa ntchito. Ma cellulosic thickeners amatha kungowonjezera gawo lamadzi, koma alibe mphamvu yowonjezereka pazigawo zina mu utoto wopangidwa ndi madzi, komanso sangathe kuyambitsa kulumikizana kwakukulu pakati pa pigment ndi emulsion particles mu utoto, kotero sangathe kusintha mawonekedwe a utoto. , Nthawi zambiri, zimatha kuwonjezera kukhuthala kwa zokutira pamitengo yotsika komanso yapakatikati (yomwe imatchedwa KU viscosity).

1. Hydroxyethyl cellulose

Mafotokozedwe ndi zitsanzo za zinthu za hydroxyethyl cellulose zimasiyanitsidwa makamaka ndi kuchuluka kwa m'malo ndi kukhuthala. Kuphatikiza pa kusiyana kwa mamasukidwe akayendedwe, mitundu ya cellulose ya hydroxyethyl imatha kugawidwa m'mitundu yosungunuka, mtundu wobalalika mwachangu komanso mtundu wokhazikika wachilengedwe mwa kusinthidwa pakupanga. Ponena za njira yogwiritsira ntchito, hydroxyethyl cellulose imatha kuwonjezeredwa pamagawo osiyanasiyana pakupangira zokutira. Mtundu wobalalitsa mofulumira ukhoza kuwonjezeredwa mwachindunji mu mawonekedwe a ufa wouma, koma pH mtengo wa dongosolo musanawonjezepo uyenera kukhala wosakwana 7, makamaka chifukwa hydroxyethyl cellulose imasungunuka pang'onopang'ono pa pH mtengo wotsika, ndipo pali nthawi yokwanira madzi kuti alowe mkati mwa tinthu tating'onoting'ono, ndiyeno onjezerani pH mtengo kuti asungunuke mwamsanga. Njira zofananira zitha kugwiritsidwanso ntchito pokonzekera guluu wamtundu wina ndikuwonjezera ku dongosolo la utoto.

2. Hydroxypropyl Methyl Cellulose

Kukhuthala kwa hydroxypropyl methylcellulose kumakhala kofanana ndi hydroxyethylcellulose, ndiko kuti, kukulitsa kukhuthala kwa zokutira pamitengo yotsika komanso yapakatikati. Hydroxypropyl methylcellulose imalimbana ndi kuwonongeka kwa enzymatic, koma kusungunuka kwake m'madzi sikofanana ndi hydroxyethyl cellulose, ndipo imakhala ndi vuto la gelling ikatenthedwa. Kwa hydroxypropyl methylcellulose yopangidwa pamwamba, imatha kuwonjezeredwa mwachindunji kumadzi ikagwiritsidwa ntchito, mutatha kusonkhezera ndi kumwaza, onjezerani zinthu zamchere monga madzi ammonia, sinthani pH mtengo kukhala 8-9, ndikugwedeza mpaka mutasungunuka. Kwa hydroxypropyl methylcellulose popanda chithandizo chapamwamba, imatha kunyowa ndikutupa ndi madzi otentha pamwamba pa 85 ° C musanagwiritse ntchito, ndiyeno itakhazikika mpaka kutentha, kenaka ndikuyambitsa madzi ozizira kapena madzi oundana kuti musungunuke.

3. Methyl cellulose

Methylcellulose ili ndi katundu wofanana ndi hydroxypropylmethylcellulose, koma imakhala yosakhazikika pamawonekedwe amanjenje ndi kutentha.

Hydroxyethyl cellulose ndiye chokhuthala chomwe chimagwiritsidwa ntchito kwambiri mu utoto wa latex, ndipo chimagwiritsidwa ntchito mu utoto wapamwamba, wapakatikati komanso wocheperako komanso utoto wokhuthala wa latex. Amagwiritsidwa ntchito kwambiri pakukula kwa utoto wamba wa latex, utoto wa imvi wa kashiamu ufa wa latex, etc. Chachiwiri ndi hydroxypropyl methylcellulose, yomwe imagwiritsidwanso ntchito pamlingo wina chifukwa cholimbikitsa opanga. Methyl cellulose sagwiritsidwa ntchito konse mu utoto wa latex, koma amagwiritsidwa ntchito kwambiri mkati ndi kunja kwa khoma putty chifukwa cha kusungunuka kwake pompopompo komanso kusunga bwino madzi. High-viscosity methyl cellulose imatha kupatsa putty ndi thixotropy wodziwika bwino komanso kusungirako madzi, ndikupangitsa kuti ikhale ndi katundu wabwino.