1. Ntchito yayikulu ya cellulose ether
Mumatope osakaniza okonzeka, cellulose ether ndi chowonjezera chachikulu chomwe chimawonjezeredwa mumtengo wochepa kwambiri koma chikhoza kupititsa patsogolo ntchito ya matope onyowa ndikukhudza ntchito yomanga matope.
2. Mitundu ya ma cellulose ethers
Kupanga kwa cellulose ether kumapangidwa makamaka ndi ulusi wachilengedwe kudzera kusungunuka kwa alkali, kulumikiza zomwe zimachitika (etherification), kutsuka, kuyanika, kugaya ndi njira zina.
Malinga ndi zida zazikulu zopangira, ulusi wachilengedwe ukhoza kugawidwa kukhala: ulusi wa thonje, ulusi wa mkungudza, ulusi wa beech, etc. Madigiri awo a polymerization amasiyana, zomwe zimakhudza kukhuthala komaliza kwa zinthu zawo.Pakadali pano, opanga ma cellulose akuluakulu amagwiritsa ntchito ulusi wa thonje (wopangidwa ndi nitrocellulose) ngati chinthu chachikulu.
Ma cellulose ether amatha kugawidwa mu ionic ndi nonionic.Mtundu wa ionic makamaka umaphatikizapo mchere wa carboxymethyl cellulose, ndipo mtundu wosakhala wa ionic umaphatikizapo methyl cellulose, methyl hydroxyethyl (propyl) cellulose, hydroxyethyl cellulose, etc.
Pakali pano, ma etha a cellulose omwe amagwiritsidwa ntchito mumatope osakanikirana ndi methyl cellulose ether (MC), methyl hydroxyethyl cellulose ether (MHEC), methyl hydroxypropyl cellulose ether (MHPG), hydroxypropyl Methyl cellulose ether (HPMC).Mumatope osakaniza okonzeka, chifukwa ionic cellulose (carboxymethyl cellulose salt) imakhala yosakhazikika pamaso pa ayoni a calcium, sagwiritsidwa ntchito kawirikawiri muzinthu zosakaniza zomwe zimagwiritsa ntchito simenti, laimu wa slaked, ndi zina zotero.M'malo ena ku China, mchere wa carboxymethyl cellulose umagwiritsidwa ntchito ngati zokometsera zinthu zina zamkati zomwe zimakonzedwa ndi wowuma wosinthidwa ngati chinthu chachikulu chomangira simenti ndi ufa wa Shuangfei ngati chodzaza.Mankhwalawa amatha kugwidwa ndi mildew ndipo sagonjetsedwa ndi madzi, ndipo tsopano akuchotsedwa.Hydroxyethyl cellulose imagwiritsidwanso ntchito pazinthu zina zosakaniza, koma ili ndi gawo laling'ono kwambiri la msika.
3. Zizindikiro zazikulu za ntchito za cellulose ether
(1) Kusungunuka
Cellulose ndi polyhydroxy polima pawiri yomwe simasungunuka kapena kusungunuka.Pambuyo pa etherification, mapadi amatha kusungunuka m'madzi, kusungunula alkali solution ndi organic solvent, ndipo amakhala ndi thermoplasticity.Solubility makamaka zimadalira zinthu zinayi: choyamba, solubility zimasiyanasiyana ndi mamasukidwe akayendedwe, m'munsi mamasukidwe akayendedwe, kwambiri solubility.Chachiwiri, makhalidwe a magulu omwe adayambitsidwa mu ndondomeko ya etherification, gulu lalikulu lomwe linayambitsa, limachepetsa kusungunuka;pamene gulu linayambitsa polar, ndi kosavuta kuti cellulose ether isungunuke m'madzi.Chachitatu, mlingo wa m'malo ndi kugawa magulu etherified mu macromolecules.Ma ether ambiri a cellulose amatha kusungunuka m'madzi pokhapokha mutalowa m'malo.Chachinayi, digiri ya polymerization wa mapadi efa, ndi apamwamba digiri ya polymerization, ndi zochepa sungunuka;m'munsi digiri ya polymerization, ndi otakata osiyanasiyana mlingo wa m'malo kuti akhoza kusungunuka m'madzi.
(2) Kusunga madzi
Kusungirako madzi ndi ntchito yofunikira ya cellulose ether, komanso ndi ntchito yomwe opanga ufa wambiri wapakhomo, makamaka omwe ali m'madera akum'mwera omwe ali ndi kutentha kwakukulu, amamvetsera.Zomwe zimakhudza momwe madzi amasungiramo matope ndi monga kuchuluka kwa cellulose ether yomwe yawonjezeredwa, kukhuthala, kununkhira kwa tinthu komanso kutentha kwa chilengedwe.Kuchuluka kwa cellulose ether kuwonjezeredwa, kumapangitsa kuti madzi asungidwe bwino;kukula kwa mamasukidwe akayendedwe, ndi bwino kuti madzi posungira zotsatira;pamene tinthu tating'onoting'ono timakhala tomwe timasunga bwino madzi.
(3) Kukhuthala
Viscosity ndi gawo lofunikira la zinthu za cellulose ether.Pakalipano, opanga ma cellulose ether osiyanasiyana amagwiritsa ntchito njira zosiyanasiyana ndi zida zoyezera kukhuthala.Kwa mankhwala omwewo, zotsatira za viscosity zoyezedwa ndi njira zosiyanasiyana ndizosiyana kwambiri, ndipo zina zimakhala zosiyana kawiri.Chifukwa chake, poyerekeza kukhuthala, kuyenera kuchitidwa pakati pa njira zoyesera zomwezo, kuphatikiza kutentha, rotor, ndi zina.
Nthawi zambiri, kukwezeka kwa mamachulukidwe kumapangitsa kuti madzi asungidwe bwino.Komabe, kukhathamiritsa kwamphamvu kwambiri, kuchuluka kwa maselo a cellulose ether, komanso kutsika kofananirako kusungunuka kwake kumakhala ndi zotsatira zoyipa pamphamvu ndi ntchito yomanga ya matope.The apamwamba mamasukidwe akayendedwe, ndi zoonekeratu kwambiri thickening zotsatira pa matope, koma si mwachindunji molingana.Kukwezeka kwa viscosity, m'pamenenso matope onyowa amawonekera kwambiri.Pakumanga, zimawonetsedwa ngati kumamatira ku scraper ndi kumamatira kwakukulu ku gawo lapansi.Koma sizothandiza kuwonjezera mphamvu zamapangidwe a dothi lonyowa palokha.Pakumanga, ntchito yotsutsa-sag sizowonekera.M'malo mwake, ma viscosity ena apakati komanso otsika koma osinthidwa a methyl cellulose ethers ali ndi ntchito yabwino kwambiri pakuwongolera mphamvu zamapangidwe amatope onyowa.
(4) Ubwino wa particles:
Ether ya cellulose yomwe imagwiritsidwa ntchito popanga matope okonzeka osakanikirana imayenera kukhala ufa, wokhala ndi madzi otsika, ndipo fineness imafunikanso 20% mpaka 60% ya kukula kwa tinthu kukhala osachepera 63 μm.Fineness imakhudza kusungunuka kwa cellulose ether.Coarse cellulose ethers nthawi zambiri amakhala ngati ma granules, omwe ndi osavuta kumwazikana ndikusungunula m'madzi popanda agglomeration, koma kusungunuka kumakhala pang'onopang'ono, kotero sikoyenera kugwiritsidwa ntchito mumatope osakaniza okonzeka (zogulitsa zina zapakhomo ndizokhazikika, osavuta kumwazikana ndi kupasuka m'madzi, ndi sachedwa caking).Mumatope osakaniza okonzeka, cellulose ether imamwazikana pakati pa ma aggregates, ma fillers abwino ndi simenti ndi zida zina zomangira.Ufa wokwanira wokwanira ungapewe kuphatikizika kwa cellulose ether mukasakaniza ndi madzi.Pamene ma cellulose ether akuwonjezeredwa ndi madzi kuti asungunuke agglomeration, zimakhala zovuta kwambiri kumwazikana ndi kupasuka.
(5) Kusintha kwa cellulose ether
Kusintha kwa cellulose ether ndiko kukulitsa ntchito yake, ndipo ndi gawo lofunikira kwambiri.The katundu mapadi ether akhoza bwino konza wettability ake, dispersibility, adhesion, thickening, emulsification, posungira madzi ndi filimu kupanga katundu, komanso impermeability ake mafuta.
4. Zotsatira za kutentha kozungulira pakusunga madzi mumatope
Kusungidwa kwa madzi kwa cellulose ether kumachepa ndi kuwonjezeka kwa kutentha.Pogwiritsira ntchito zinthu zothandiza, matope nthawi zambiri amagwiritsidwa ntchito pazigawo zotentha kwambiri (kupitirira 40 ° C) m'madera ambiri.Kutsika kwa kusungidwa kwa madzi kunapangitsa kuti pakhale chiwopsezo chowonekera pakugwira ntchito komanso kukana ming'alu.Kudalira kwake kutentha kudzachititsabe kufooka kwa zinthu zamatope, ndipo ndizofunikira kwambiri kuchepetsa mphamvu ya kutentha pansi pa chikhalidwe ichi.Maphikidwe amatope adasinthidwa moyenera, ndipo kusintha kwakukulu kunapangidwa m'maphikidwe a nyengo.Ngakhale kuonjezera mlingo (chilinganizo cha chilimwe), kugwira ntchito ndi kukana kwa mng'alu sikungathe kukwaniritsa zofunikira zogwiritsira ntchito, zomwe zimafuna chithandizo chapadera cha cellulose ether, monga kuonjezera mlingo wa etherification, ndi zina zotero, kotero kuti mphamvu yosungira madzi ikhoza kukhala zimatheka pa kutentha kwambiri.Imakhala ndi zotsatira zabwino pamene ili pamwamba, kotero kuti imapereka ntchito yabwino muzochitika zovuta.
5. Kugwiritsa ntchito mumatope osakaniza okonzeka
Mumatope osakaniza okonzeka, cellulose ether imagwira ntchito yosungira madzi, kulimbitsa ndi kupititsa patsogolo ntchito yomanga.Kuchita bwino kwa kusunga madzi kumapangitsa kuti matopewo asapangitse mchenga, ufa ndi kuchepetsa mphamvu chifukwa cha kusowa kwa madzi ndi kusakwanira kwa madzi.The thickening zotsatira kwambiri timapitiriza structural mphamvu ya chonyowa matope.Kuwonjezera pa cellulose ether akhoza kwambiri kusintha kukhuthala konyowa wa chonyowa matope, ndipo ali mamasukidwe akayendedwe bwino magawo osiyanasiyana, potero kuwongolera khoma ntchito yonyowa matope ndi kuchepetsa zinyalala.Kuphatikiza apo, ntchito ya cellulose ether muzinthu zosiyanasiyana ndi yosiyana.Mwachitsanzo, mu zomatira matailosi, cellulose ether imatha kuwonjezera nthawi yotsegulira ndikusintha nthawi;mu makina kupopera mbewu mankhwalawa matope, akhoza kusintha structural mphamvu ya chonyowa matope;pakudziyimira pawokha, zitha kupewa kukhazikika, Kupatulana komanso kusanja.Choncho, monga chowonjezera chofunikira, cellulose ether imagwiritsidwa ntchito kwambiri mumatope a ufa wouma.
Nthawi yotumiza: Jan-11-2023