Mumatope osakaniza okonzeka, kuchuluka kwa cellulose ether kumakhala kochepa kwambiri, koma kungathe kusintha kwambiri ntchito yamatope, ndipo ndi chowonjezera chachikulu chomwe chimakhudza ntchito yomanga matope. Kusankhidwa koyenera kwa ma cellulose ethers amitundu yosiyanasiyana, ma viscosity osiyanasiyana, makulidwe osiyanasiyana a tinthu, magawo osiyanasiyana a mamasukidwe akayendedwe ndi kuchuluka kowonjezera kudzakhala ndi zotsatira zabwino pakuchita bwino kwa matope owuma a ufa. Pakalipano, matope ambiri omanga ndi pulasitala sakhala ndi ntchito yabwino yosungira madzi, ndipo matope amadzi amalekanitsidwa pakangopita mphindi zochepa. Kusungirako madzi ndi ntchito yofunikira ya methyl cellulose ether, komanso ndikuchitanso komwe opanga matope ambiri am'nyumba, makamaka omwe ali kumadera akum'mwera komwe kumatentha kwambiri, amalabadira. Zomwe zimakhudza momwe madzi amasungiramo matope owuma akuphatikizapo kuchuluka kwa MC yowonjezeredwa, kukhuthala kwa MC, kununkhira kwa tinthu tating'ono komanso kutentha kwa chilengedwe.
1. Lingaliro
Cellulose ether ndi polima wopangidwa kuchokera ku cellulose wachilengedwe kudzera mukusintha kwamankhwala. Cellulose ether ndi chochokera ku cellulose yachilengedwe. Kupanga kwa cellulose ether ndikosiyana ndi ma polima opangira. Zinthu zake zofunika kwambiri ndi cellulose, gulu lachilengedwe la polima. Chifukwa cha mawonekedwe achilengedwe a cellulose, cellulose palokha sangathe kuchitapo kanthu ndi etherification agents. Komabe, pambuyo pochiza chotupa chotupa, zomangira zamphamvu za haidrojeni pakati pa unyolo wa maselo ndi unyolo zimawonongeka, ndipo kutulutsidwa kogwira kwa gulu la hydroxyl kumakhala cellulose yotakata. Pezani cellulose ether.
Makhalidwe a cellulose ethers amadalira mtundu, chiwerengero ndi kugawa kwa zolowa m'malo. Magulu a cellulose ethers amatengeranso mtundu wa zolowa m'malo, digiri ya etherification, solubility ndi mawonekedwe ogwiritsira ntchito. Malinga ndi mtundu wa zolowa m'malo pa unyolo wa maselo, zitha kugawidwa mu monoether ndi ether wosakanikirana. MC yomwe timagwiritsa ntchito nthawi zambiri ndi monoether, ndipo HPMC ndi ether yosakanikirana. Methyl cellulose ether MC ndi chinthu chopangidwa pambuyo poti gulu la hydroxyl pagawo la shuga la cellulose wachilengedwe lilowe m'malo ndi methoxy. Ndi chinthu chopezedwa polowa m'malo mwa gulu la hydroxyl pagawo ndi gulu la methoxy ndi gawo lina ndi gulu la hydroxypropyl. Mapangidwe ake ndi [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethyl methyl cellulose ether HEMC, iyi ndi mitundu ikuluikulu yomwe imagwiritsidwa ntchito kwambiri ndikugulitsidwa pamsika.
Pankhani ya solubility, imatha kugawidwa kukhala ionic ndi non-ionic. Ma etha osungunuka m'madzi omwe si a ionic cellulose amapangidwa makamaka ndi ma alkyl ethers ndi ma hydroxyalkyl ethers. Ionic CMC imagwiritsidwa ntchito makamaka mu zotsukira zopangira, kusindikiza nsalu ndi utoto, kufufuza zakudya ndi mafuta. Non-ionic MC, HPMC, HEMC, etc. amagwiritsidwa ntchito makamaka muzomangamanga, zokutira latex, mankhwala, mankhwala tsiku ndi tsiku, etc. Amagwiritsidwa ntchito ngati thickener, madzi kusunga wothandizira, stabilizer, dispersant ndi filimu kupanga wothandizira.
Chachiwiri, kusungirako madzi kwa cellulose ether
Kusungirako madzi a cellulose ether: Popanga zida zomangira, makamaka matope a ufa wowuma, ether ya cellulose imagwira ntchito yosasinthika, makamaka popanga matope apadera (matope osinthidwa), ndi gawo lofunikira komanso lofunikira .
Ntchito yofunika kwambiri ya madzi sungunuka mapadi etero mu matope makamaka ali mbali zitatu, mmodzi kwambiri madzi posungira mphamvu, wina ndi chikoka pa kusasinthasintha ndi thixotropy wa matope, ndipo chachitatu ndi mogwirizana ndi simenti. Mphamvu yosungira madzi ya cellulose ether imadalira kuyamwa kwamadzi kwa gawo loyambira, kapangidwe ka matope, makulidwe a matope, kuchuluka kwa madzi kwa matope, komanso nthawi yoyika zinthu. Kusungidwa kwamadzi kwa cellulose ether komweko kumachokera ku kusungunuka ndi kutaya madzi m'thupi kwa cellulose ether yokha. Monga ife tonse tikudziwa, ngakhale cellulose maselo unyolo muli ambiri hydratable OH magulu kwambiri hydratable, si sungunuka m'madzi, chifukwa mapadi kapangidwe ndi mkulu digiri crystallinity.
Mphamvu ya hydration yamagulu a hydroxyl yokha sikokwanira kuphimba zomangira zamphamvu za haidrojeni ndi mphamvu za van der Waals pakati pa mamolekyu. Choncho, zimangotupa koma sizisungunuka m'madzi. Pamene cholowa m'malo anadzetsa mu unyolo maselo, osati m'malo kuwononga unyolo wa haidrojeni, komanso interchain wa haidrojeni chomangira anawonongedwa chifukwa wedging wa m'malo pakati moyandikana unyolo. Cholowa m'malo chimakhala chachikulu, ndiye kuti mtunda wapakati pa mamolekyu ndi waukulu. Kuchuluka kwa mtunda. Zotsatira zazikulu za kuwononga zomangira za haidrojeni, cellulose ether imakhala yosungunuka m'madzi pambuyo poti latisi ya cellulose ikuchulukira ndipo yankho limalowa, ndikupanga yankho lapamwamba kwambiri. Kutentha kukakwera, hydration ya polima imafooka, ndipo madzi pakati pa maunyolo amathamangitsidwa. Pamene kuchepa madzi m'thupi zotsatira zokwanira, mamolekyu amayamba aggregate, kupanga atatu azithunzithunzi maukonde dongosolo gel osakaniza ndi apangidwe kunja.
Zomwe zimakhudza kasungidwe kamadzi mumatope ndi monga cellulose ether viscosity, kuchuluka kowonjezera, kununkhira kwa tinthu ndi kutentha kwa ntchito:
Kuchuluka kwa kukhuthala kwa cellulose ether, kumapangitsa kuti madzi asungidwe bwino. Viscosity ndi gawo lofunikira la magwiridwe antchito a MC. Pakadali pano, opanga ma MC osiyanasiyana amagwiritsa ntchito njira ndi zida zosiyanasiyana kuyeza kukhuthala kwa MC. Njira zazikulu ndi Haake Rotovisko, Hoppler, Ubbelohde ndi Brookfield. Kwa mankhwala omwewo, zotsatira za viscosity zoyezedwa ndi njira zosiyanasiyana ndizosiyana kwambiri, ndipo zina zimakhala zosiyana kawiri. Chifukwa chake, poyerekeza kukhuthala, kuyenera kuchitika pakati pa njira zoyesera zomwezo, kuphatikiza kutentha, rotor, ndi zina.
Nthawi zambiri, kukwezeka kwa mamachulukidwe kumapangitsa kuti madzi asungidwe bwino. Komabe, kukwezeka kwa mamachulukidwe apamwamba komanso kulemera kwa mamolekyu a MC, kutsika kofananirako kusungunuka kwake kudzakhala ndi zotsatira zoyipa pamphamvu ndi ntchito yomanga ya matope. The apamwamba mamasukidwe akayendedwe, ndi zoonekeratu kwambiri thickening zotsatira pa matope, koma si mwachindunji molingana. Kukwera kwa mamasukidwe akayendedwe, m'pamenenso matope onyowa amakhala owoneka bwino kwambiri, ndiye kuti, pakumanga, amawonetsedwa 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.
Kuchuluka kwa cellulose ether kuwonjezeredwa kumatope, kumapangitsa kuti madzi asamasungidwe bwino, komanso kukwezeka kwa viscosity, ndi bwino kusunga madzi.
Ponena za kukula kwa tinthu tating'onoting'ono, tinthu tating'onoting'ono timasunga bwino madzi. Pambuyo pa tinthu tating'ono ta cellulose ether takumana ndi madzi, pamwamba pake nthawi yomweyo amasungunuka ndikupanga gel osakaniza kuti ateteze mamolekyu amadzi kuti asapitirire kulowa. Nthawi zina sangathe kumwazikana mofanana ndi kusungunuka ngakhale atagwedezeka kwa nthawi yaitali, kupanga njira yothetsera mitambo kapena agglomeration. Zimakhudza kwambiri kusungidwa kwamadzi kwa cellulose ether, ndipo kusungunuka ndi chimodzi mwazinthu zomwe zimasankha cellulose ether.
Fineness ndiwonso index yofunikira ya methyl cellulose ether. The MC ntchito youma ufa matope chofunika kukhala ufa, ndi okhutira madzi otsika, ndi fineness amafunanso 20% ~ 60% ya tinthu kukula kukhala zosakwana 63um. Ubwino wake umakhudza kusungunuka kwa methyl cellulose ether. Coarse MC nthawi zambiri imakhala granular, ndipo ndiyosavuta kusungunuka m'madzi popanda agglomeration, koma kusungunuka kumakhala pang'onopang'ono, kotero sikoyenera kugwiritsidwa ntchito mumatope a ufa wouma. Mu matope owuma a ufa, MC imamwazikana pakati pa zinthu zopangira simenti monga zophatikiza, zodzaza bwino ndi simenti, ndipo ufa wokwanira wokwanira ungapewe methyl cellulose ether agglomeration mukasakaniza ndi madzi. Pamene MC ikuwonjezeredwa ndi madzi kuti asungunuke ma agglomerates, zimakhala zovuta kwambiri kumwazikana ndi kupasuka.
Coarse fineness wa MC sikungowononga, komanso kumachepetsa mphamvu yakomweko ya matope. Pamene matope owuma owuma akugwiritsidwa ntchito m'dera lalikulu, kuthamanga kwa machiritso a matope owuma a m'deralo kudzachepetsedwa kwambiri, ndipo ming'alu idzawoneka chifukwa cha nthawi zosiyanasiyana zochiritsira. Kwa matope opopera omwe amapangidwa ndi makina, kufunikira kwa fineness ndipamwamba chifukwa cha nthawi yochepa yosakaniza.
Ubwino wa MC umakhalanso ndi vuto linalake pakusunga madzi. Nthawi zambiri, ma etha a methyl cellulose okhala ndi kukhuthala kofanana koma fineness yosiyana, pansi pa kuchuluka komweko, kuwongolera bwino kumapangitsa kuti madzi asungidwe bwino.
Kusungidwa kwa madzi kwa MC kumagwirizananso ndi kutentha komwe kumagwiritsidwa ntchito, ndipo kusunga madzi kwa methyl cellulose ether kumachepa ndi kuwonjezeka kwa kutentha. Komabe, muzinthu zenizeni, matope a ufa wowuma nthawi zambiri amagwiritsidwa ntchito kumalo otentha kwambiri (oposa madigiri 40) m'madera ambiri, monga kunja kwa khoma la putty pulasitala pansi pa dzuwa m'chilimwe, zomwe nthawi zambiri zimathandizira Kuchiritsa simenti ndi kuumitsa kwa simenti. ufa wouma matope. Kutsika kwa kuchuluka kwa madzi osungira madzi kumabweretsa kumverera koonekeratu kuti zonse zogwira ntchito komanso kukana kwa ming'alu zimakhudzidwa, ndipo ndizofunikira kwambiri kuchepetsa mphamvu ya kutentha pansi pa chikhalidwe ichi.
Ngakhale kuti zowonjezera za methyl hydroxyethyl cellulose ether panopa zimaonedwa kuti ndizo patsogolo pa chitukuko cha zamakono, kudalira kwawo kutentha kudzapitirizabe kufooketsa ntchito ya ufa wouma. Ngakhale kuchuluka kwa methyl hydroxyethyl cellulose kumachulukitsidwa (chilinganizo cha chilimwe), kugwira ntchito ndi kukana kwa crack sikungakwaniritse zosowa zogwiritsidwa ntchito. Kupyolera mu chithandizo chapadera pa MC, monga kuonjezera mlingo wa etherification, ndi zina zotero, zotsatira zosungira madzi zimatha kusungidwa pa kutentha kwakukulu, kotero kuti zitha kupereka ntchito yabwino pansi pa zovuta.
3. Makulidwe ndi Thixotropy wa Cellulose Ether
Kukhuthala ndi thixotropy wa mapadi efa: Ntchito yachiwiri ya mapadi etere - thickening zotsatira zimadalira: mlingo wa polymerization wa mapadi efa, njira ndende, kukameta ubweya mlingo, kutentha ndi zina. Katundu wa gelling wa yankho ndi wapadera kwa alkyl cellulose ndi zotuluka zake zosinthidwa. Makhalidwe a gelation amakhudzana ndi kuchuluka kwa m'malo, ndende ya yankho ndi zowonjezera. Kwa zotumphukira zosinthidwa za hydroxyalkyl, mawonekedwe a gel amalumikizananso ndi digiri yosinthidwa ya hydroxyalkyl. Pakuti otsika mamasukidwe akayendedwe MC ndi HPMC, 10% -15% yankho akhoza kukonzekera, sing'anga mamasukidwe akayendedwe MC ndi HPMC akhoza kukonzekera 5% -10% yankho, pamene mkulu mamasukidwe akayendedwe MC ndi HPMC akhoza kukonzekera 2% -3% yankho, ndipo Kawirikawiri Gulu la mamasukidwe a cellulose ether limayikidwanso ndi 1% -2% yankho.
High molecular kulemera cellulose ether ali mkulu thickening dzuwa. Munjira yofananira, ma polima okhala ndi zolemetsa zosiyanasiyana zama cell amakhala ndi ma viscosity osiyanasiyana. Madigiri apamwamba. Kukhuthala kwa chandamale kungatheke pokhapokha powonjezera kuchuluka kwa maselo otsika a cellulose ether. Kukhuthala kwake kumadalira pang'ono kumeta ubweya wa ubweya, ndipo kukhuthala kwapamwamba kumafika kukhuthala kwa chandamale, ndipo kuchuluka komwe kumafunikira kumakhala kochepa, ndipo kukhuthala kumadalira kukhuthala kwamphamvu. Choncho, kuti akwaniritse kusasinthasintha kwina, kuchuluka kwa cellulose ether (kukhazikika kwa yankho) ndi kukhuthala kwa njira ziyenera kutsimikiziridwa. Kutentha kwa gel osakaniza kumachepetsanso mofanana ndi kuwonjezeka kwa ndende ya yankho, ndi gel osakaniza kutentha kwa firiji atatha kufika pamtundu wina. The gelling ndende ya HPMC ndi mkulu kutentha firiji.
Kusasinthasintha kungasinthidwenso posankha kukula kwa tinthu ndikusankha ma cellulose ethers ndi magawo osiyanasiyana akusintha. Zomwe zimatchedwa kusinthidwa ndikuyambitsa njira ina yosinthira magulu a hydroxyalkyl pamapangidwe a mafupa a MC. Posintha zikhalidwe zolowa m'malo mwazolowa m'malo awiriwo, ndiye kuti, DS ndi ms m'malo mwa magulu a methoxy ndi hydroxyalkyl omwe timanena nthawi zambiri. Zofunikira zosiyanasiyana zogwirira ntchito za cellulose ether zitha kupezeka posintha kusintha kwazinthu ziwirizo.
Ubale pakati pa kusasinthasintha ndi kusinthidwa: kuwonjezeredwa kwa cellulose ether kumakhudza kumwa madzi kwa matope, kusintha madzi-binder chiŵerengero cha madzi ndi simenti ndi thickening zotsatira, apamwamba mlingo, kwambiri kumwa madzi.
Ma cellulose ethers omwe amagwiritsidwa ntchito muzomangamanga za ufa ayenera kusungunuka mwachangu m'madzi ozizira ndikupereka kusasinthika koyenera kwa dongosolo. Ngati atapatsidwa kumeta ubweya wina, amakhalabe wopindika komanso wamtundu wa colloidal, womwe ndi chinthu chotsikirapo kapena chosawoneka bwino.
Palinso ubale wabwino wa mzere pakati pa kusasinthika kwa phala la simenti ndi mlingo wa cellulose ether. Selulosi ether akhoza kwambiri kuonjezera mamasukidwe akayendedwe a matope. Mlingo waukulu kwambiri, zotsatira zake zimakhala zoonekeratu. High-viscosity cellulose ether amadzimadzi njira ali mkulu thixotropy, amenenso ndi khalidwe lalikulu la mapadi ether. Amadzimadzi njira za MC ma polima zambiri pseudoplastic ndi sanali thixotropic fluidity m'munsimu awo gel osakaniza kutentha, koma Newtonian otaya katundu pa otsika kukameta ubweya mitengo. Pseudoplasticity imawonjezeka ndi kulemera kwa maselo kapena kuchuluka kwa cellulose ether, mosasamala kanthu za mtundu wa cholowa m'malo ndi kuchuluka kwa m'malo. Choncho, ma cellulose ethers a kalasi yofanana ya viscosity, mosasamala kanthu za MC, HPMC, HEMC, nthawi zonse amawonetsa zofanana za rheological malinga ngati ndende ndi kutentha zimasungidwa nthawi zonse.
Ma gels apangidwe amapangidwa pamene kutentha kumakwera, ndipo kutuluka kwa thixotropic kwambiri kumachitika. Mkulu ndende ndi otsika mamasukidwe akayendedwe mapadi ethers amasonyeza thixotropy ngakhale pansi pa kutentha gel osakaniza. Katunduyu ndiwopindulitsa kwambiri pakuwongolera kusanja ndi kugwa pakupanga matope omangira. Payenera kufotokozedwa apa kuti kukwezeka kwa kukhuthala kwa cellulose ether, kusungika kwamadzi kwabwino, koma kukhuthala kwamphamvu, kumapangitsanso kuchuluka kwa maselo a cellulose ether, komanso kuchepa kofananira ndi kusungunuka kwake, komwe kumakhala ndi zotsatira zoyipa. pa ndende yamatope ndi ntchito yomanga. The apamwamba mamasukidwe akayendedwe, zoonekeratu kwambiri thickening zotsatira pa matope, koma si kwathunthu molingana. Kukhuthala kwina kwapakatikati ndi kotsika, koma ether yosinthidwa ya cellulose imakhala ndi magwiridwe antchito abwino pakuwongolera mphamvu zamapangidwe amatope onyowa. Ndi kuwonjezeka kwa mamasukidwe akayendedwe, kasungidwe kamadzi ka cellulose ether kumapita bwino. 4. Kuchedwa kwa cellulose ether
Kuchedwetsa kwa cellulose ether: Ntchito yachitatu ya cellulose ether ndiyo kuchedwetsa hydration ya simenti. Ma cellulose ether amawonjezera matope okhala ndi zinthu zosiyanasiyana zopindulitsa, komanso amachepetsa kutentha koyambirira kwa simenti ndikuchedwetsa hydration dynamic process ya simenti. Izi sizothandiza kugwiritsa ntchito matope m'madera ozizira. Kuchedwetsaku kumachitika chifukwa cha kutengeka kwa ma cellulose ether mamolekyu pa zinthu za hydration monga CSH ndi ca(OH)2. Chifukwa cha kuchuluka kwa mamasukidwe akayendedwe a pore yankho, mapadi ether amachepetsa kuyenda kwa ayoni mu yankho, potero kuchedwa hydration ndondomeko.
Nthawi yotumiza: Feb-04-2023