Mu matope osakaniza bwino, kuchuluka kwa ether ya cellulose kumakhala kochepa kwambiri, koma kumatha kusintha kwambiri magwiridwe antchito a matope onyowa, ndipo ndi chowonjezera chachikulu chomwe chimakhudza magwiridwe antchito a matope. Kusankha bwino ma ether a cellulose amitundu yosiyanasiyana, kukhuthala kosiyana, kukula kosiyana kwa tinthu tating'onoting'ono, madigiri osiyanasiyana a kukhuthala ndi kuchuluka kowonjezera kudzakhudza bwino magwiridwe antchito a matope ouma. Pakadali pano, matope ambiri opangidwa ndi miyala ndi pulasitala ali ndi magwiridwe antchito osasunga madzi, ndipo matope amadzi amasiyana patatha mphindi zochepa atayima. Kusunga madzi ndi ntchito yofunika kwambiri ya methyl cellulose ether, ndipo ndi ntchito yomwe opanga matope ambiri osakaniza madzi m'nyumba, makamaka omwe ali m'madera akumwera okhala ndi kutentha kwambiri, amalabadira. Zinthu zomwe zimakhudza momwe matope osakaniza madzi amasungira madzi ndi monga kuchuluka kwa MC yowonjezera, kukhuthala kwa MC, kusalala kwa tinthu tating'onoting'ono ndi kutentha kwa malo ogwiritsidwa ntchito.
1. Lingaliro
Cellulose ether ndi polima yopangidwa kuchokera ku cellulose yachilengedwe kudzera mu kusintha kwa mankhwala. Cellulose ether ndi yochokera ku cellulose yachilengedwe. Kupanga kwa cellulose ether ndi kosiyana ndi ma polima opangidwa. Zinthu zake zofunika kwambiri ndi cellulose, chinthu chachilengedwe cha polymer. Chifukwa cha kapangidwe ka cellulose yachilengedwe, cellulose yokha ilibe mphamvu yochitapo kanthu ndi zinthu zoyeretsera. Komabe, pambuyo pochiza chotupa, ma hydrogen amphamvu pakati pa unyolo wa mamolekyu ndi unyolo amawonongeka, ndipo kutulutsidwa kwa hydroxyl kumayamba kukhala reactive alkali cellulose. Pezani cellulose ether.
Katundu wa ma ether a cellulose amadalira mtundu, chiwerengero ndi kufalikira kwa ma ether. Kugawidwa kwa ma ether a cellulose kumadaliranso mtundu wa ma ether, kuchuluka kwa ether, kusungunuka ndi mawonekedwe ofanana ndi omwe amagwiritsidwa ntchito. Malinga ndi mtundu wa ma ether omwe ali pa unyolo wa molekyulu, amatha kugawidwa m'magulu awiri: monoether ndi mixed ether. MC yomwe timagwiritsa ntchito nthawi zambiri ndi monoether, ndipo HPMC ndi mixed ether. Methyl cellulose ether MC ndi chinthu chomwe chimachitika pambuyo poti gulu la hydroxyl pa unit ya glucose ya cellulose yachilengedwe yasinthidwa ndi methoxy. Ndi chinthu chomwe chimapezeka posintha gawo la gulu la hydroxyl pa unit ndi gulu la methoxy ndi gawo lina ndi gulu la hydroxypropyl. Fomula yomangira ndi [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethylmethyl cellulose ether HEMC, awa ndi mitundu yayikulu yomwe imagwiritsidwa ntchito kwambiri komanso yogulitsidwa pamsika.
Ponena za kusungunuka, ikhoza kugawidwa m'magulu a ionic ndi non-ionic. Ma ether a cellulose osungunuka m'madzi amapangidwa makamaka ndi ma ether awiri a alkyl ndi ma ether a hydroxyalkyl. Ionic CMC imagwiritsidwa ntchito kwambiri mu sopo yopangira, kusindikiza ndi kupaka utoto nsalu, kufufuza chakudya ndi mafuta. Non-ionic MC, HPMC, HEMC, ndi zina zotero zimagwiritsidwa ntchito kwambiri mu zipangizo zomangira, zokutira za latex, mankhwala, mankhwala a tsiku ndi tsiku, ndi zina zotero. Amagwiritsidwa ntchito ngati chokhuthala, chosungira madzi, chokhazikika, chosungunula ndi chopangira filimu.
Chachiwiri, kusunga madzi kwa efa ya cellulose
Kusunga madzi kwa etha ya cellulose: Pakupanga zipangizo zomangira, makamaka matope ouma, etha ya cellulose imagwira ntchito yosasinthika, makamaka pakupanga matope apadera (matope osinthidwa), ndi gawo lofunika kwambiri komanso lofunikira.
Udindo wofunikira wa etha yosungunuka m'madzi mu matope uli ndi mbali zitatu, imodzi ndi mphamvu yabwino kwambiri yosungira madzi, ina ndi momwe matope amagwirira ntchito komanso thixotropy, ndipo yachitatu ndi momwe simenti imagwirira ntchito. Mphamvu yosungira madzi ya etha yosungunuka m'madzi imadalira kuyamwa kwa madzi kwa gawo loyambira, kapangidwe ka matope, makulidwe a gawo losungunuka, kufunika kwa madzi kwa matope, komanso nthawi yoyika zinthu. Kusunga madzi kwa etha yosungunuka m'madzi kumachokera ku kusungunuka ndi kuchepa kwa madzi kwa etha yosungunuka m'madzi. Monga tonse tikudziwira, ngakhale kuti unyolo wa maselo a cellulose uli ndi magulu ambiri a OH omwe amatha kusungunuka, susungunuka m'madzi, chifukwa kapangidwe ka cellulose kali ndi kristalo wambiri.
Mphamvu ya hydration ya magulu a hydroxyl yokha sikokwanira kuphimba ma hydrogen bond amphamvu ndi mphamvu za van der Waals pakati pa mamolekyulu. Chifukwa chake, imangotupa koma siisungunuka m'madzi. Pamene substituent ilowetsedwa mu unyolo wa mamolekyulu, sikuti substituent yokha imawononga unyolo wa hydrogen, komanso hydrogen bond yolumikizana imawonongeka chifukwa cha kuyanjana kwa substituent pakati pa ma chain oyandikana nawo. Pamene substituent ikukula, mtunda pakati pa mamolekyulu umakula. Mtunda umakula. Pamene zotsatira za kuwononga ma hydrogen bond zikukulirakulira, cellulose ether imasungunuka m'madzi pambuyo poti cellulose lattice yakula ndipo yankho limalowa, ndikupanga yankho la high-viscosity. Pamene kutentha kukukwera, hydration ya polima imafooka, ndipo madzi pakati pa ma chain amatulutsidwa kunja. Pamene zotsatira za kusowa madzi okwanira, mamolekyu amayamba kusonkhana, kupanga gel yomanga maukonde atatu ndikupindika.
Zinthu zomwe zimakhudza kusunga madzi mu matope ndi monga kukhuthala kwa ether ya cellulose, kuchuluka kwa kuwonjezera, kusalala kwa tinthu tating'onoting'ono ndi kutentha kwa ntchito:
Kukhuthala kwa etha ya cellulose kukakula, kumakhala bwino kwambiri pakusunga madzi. Kukhuthala ndi gawo lofunika kwambiri pakugwira ntchito kwa MC. Pakadali pano, opanga osiyanasiyana a MC amagwiritsa ntchito njira ndi zida zosiyanasiyana poyesa kukhuthala kwa MC. Njira zazikulu ndi Haake Rotovisko, Hoppler, Ubbelohde ndi Brookfield. Pa chinthu chomwecho, zotsatira za kukhuthala zomwe zimayesedwa ndi njira zosiyanasiyana zimakhala zosiyana kwambiri, ndipo zina zimakhala ndi kusiyana kawiri. Chifukwa chake, poyerekeza kukhuthala, ziyenera kuchitika pakati pa njira zomwezo zoyesera, kuphatikiza kutentha, rotor, ndi zina zotero.
Kawirikawiri, kukhuthala kwa madzi kukakhala kwakukulu, kumakhala bwino kwambiri. Komabe, kukhuthala kwa madzi kukakhala kwakukulu komanso kulemera kwa molekyulu ya MC, kuchepa kofanana kwa kusungunuka kwake kudzakhala ndi zotsatira zoyipa pa mphamvu ndi magwiridwe antchito a matope. Kukhuthala kwa madzi kukakhala kwakukulu, kukhuthala kwa matope kumakhala koonekera bwino, koma sikufanana mwachindunji. Kukhuthala kwa madzi kukakhala kwakukulu, kukhuthala kwa matope onyowa kumakhala kolimba kwambiri, ndiko kuti, panthawi yomanga, kumaonekera ngati kumamatira ku scraper ndi kumamatira kwambiri ku substrate. Koma sizothandiza kuwonjezera mphamvu ya matope onyowa okha. Panthawi yomanga, mphamvu yotsutsana ndi kusagwa siidziwika. M'malo mwake, ma ether ena apakatikati ndi otsika koma osinthidwa a methyl cellulose ali ndi magwiridwe antchito abwino kwambiri pakukweza mphamvu ya matope onyowa.
Kuchuluka kwa ether ya cellulose yomwe yawonjezeredwa ku matope, kumakhala bwino kusunga madzi, ndipo kukhuthala kwake kumakhala kwakukulu, kumakhala bwino kusunga madzi.
Ponena za kukula kwa tinthu, tinthu tating'onoting'ono tikakhala tating'onoting'ono, madzi amasungidwa bwino. Tinthu tating'onoting'ono ta cellulose ether tikakumana ndi madzi, pamwamba pake pamadziwo timasungunuka nthawi yomweyo ndikupanga gel yokulunga zinthuzo kuti mamolekyu amadzi asapitirire kulowa. Nthawi zina sizingafalitsidwe mofanana ndikusungunuka ngakhale mutasakaniza kwa nthawi yayitali, ndikupanga yankho la mitambo kapena agglomeration. Zimakhudza kwambiri kusungidwa kwa madzi kwa cellulose ether, ndipo kusungunuka ndi chimodzi mwazinthu zomwe zimasankhidwa posankha cellulose ether.
Kusalala ndi chizindikiro chofunikira cha ntchito ya methyl cellulose ether. MC yomwe imagwiritsidwa ntchito pa matope ouma amafunika kukhala ufa, wokhala ndi madzi ochepa, ndipo kusalala kwake kumafunanso 20% ~ 60% ya kukula kwa tinthu kuti ikhale yochepera 63um. Kusalala kumeneku kumakhudza kusungunuka kwa methyl cellulose ether. MC yolimba nthawi zambiri imakhala ndi granular, ndipo imakhala yosavuta kusungunuka m'madzi popanda kusonkhana, koma kuchuluka kwa kusungunuka kumakhala pang'onopang'ono kwambiri, kotero sikoyenera kugwiritsidwa ntchito mu matope ouma. Mu matope ouma, MC imafalikira pakati pa zinthu zomangira simenti monga aggregate, final filler ndi simenti, ndipo ufa wokwanira wokha ndi womwe ungapewe kusonkhana kwa methyl cellulose ether mukasakaniza ndi madzi. MC ikawonjezedwa ndi madzi kuti isungunuke ma agglomerate, zimakhala zovuta kwambiri kufalitsa ndi kusungunula.
Kusalala kwa MC sikuti kungowononga ndalama zokha, komanso kumachepetsa mphamvu ya matope ouma. Mukayika matope ouma otere pamalo akuluakulu, liwiro louma la matope ouma ouma limachepa kwambiri, ndipo ming'alu idzawonekera chifukwa cha nthawi zosiyanasiyana zouma. Pa matope opopera ndi makina opangidwa, kufunikira kwa matope ouma kumakhala kwakukulu chifukwa cha nthawi yochepa yosakaniza.
Kusalala kwa MC kumakhudzanso kusunga madzi. Kawirikawiri, pa ma ether a methyl cellulose omwe ali ndi kukhuthala kofanana koma kusalala kosiyana, pansi pa kuchuluka komweko kowonjezera, kusalala kocheperako kumakhala bwino pakusunga madzi.
Kusunga madzi kwa MC kumagwirizananso ndi kutentha komwe kumagwiritsidwa ntchito, ndipo kusunga madzi kwa methyl cellulose ether kumachepa ndi kuwonjezeka kwa kutentha. Komabe, pakugwiritsa ntchito zinthu zenizeni, matope owuma nthawi zambiri amagwiritsidwa ntchito pazigawo zotentha kutentha kwambiri (koposa madigiri 40) m'malo ambiri, monga kuyika pulasitala padenga lakunja pansi pa dzuwa nthawi yachilimwe, zomwe nthawi zambiri zimathandizira Kukonza simenti ndi kuuma kwa matope owuma. Kutsika kwa kuchuluka kwa kusunga madzi kumabweretsa kumverera koonekeratu kuti kukana kugwira ntchito komanso kukana ming'alu kumakhudzidwa, ndipo ndikofunikira kwambiri kuchepetsa mphamvu ya zinthu zotentha pansi pa vutoli.
Ngakhale kuti zowonjezera za methyl hydroxyethyl cellulose ether zikuonedwa kuti zili patsogolo pa chitukuko cha ukadaulo, kudalira kwawo kutentha kudzapangitsabe kufooka kwa magwiridwe antchito a matope ouma. Ngakhale kuchuluka kwa methyl hydroxyethyl cellulose kukuwonjezeka (njira yachilimwe), kulimba kwa ntchito ndi kukana ming'alu sikungakwaniritse zosowa zogwiritsidwa ntchito. Kudzera mu chithandizo chapadera pa MC, monga kuwonjezera kuchuluka kwa etherification, ndi zina zotero, mphamvu yosungira madzi imatha kusungidwa kutentha kwambiri, kuti ipereke magwiridwe antchito abwino pansi pa mikhalidwe yovuta.
3. Kukhuthala ndi Thixotropy ya Cellulose Ether
Kukhuthala ndi thixotropy ya cellulose ether: Ntchito yachiwiri ya cellulose ether—kukhuthala kumadalira: kuchuluka kwa polymerization ya cellulose ether, kuchuluka kwa yankho, kuchuluka kwa shear, kutentha ndi zina. Kapangidwe ka gelling ka yankho ndi kapadera kwa alkyl cellulose ndi zotumphukira zake zosinthidwa. Kapangidwe ka gelation kamagwirizana ndi kuchuluka kwa kusintha, kuchuluka kwa yankho ndi zowonjezera. Pa zotumphukira zosinthidwa za hydroxyalkyl, kapangidwe ka gel kamagwirizananso ndi kuchuluka kwa kusintha kwa hydroxyalkyl. Pa kukhuthala kochepa kwa MC ndi HPMC, yankho la 10%-15% likhoza kukonzedwa, kukhuthala kwapakati kwa MC ndi HPMC kumatha kukonzedwa yankho la 5%-10%, pomwe kukhuthala kwakukulu kwa MC ndi HPMC kumatha kukonzekeretsa yankho la 2%-3%, ndipo Nthawi zambiri gulu la kukhuthala kwa cellulose ether limayesedwanso ndi yankho la 1%-2%.
Etha ya cellulose yolemera kwambiri imakhala ndi mphamvu yokhuthala kwambiri. Mu yankho lomwelo, ma polima okhala ndi kulemera kosiyanasiyana kwa ma molekyulu amakhala ndi kukhuthala kosiyana. Mlingo wapamwamba. Kukhuthala komwe kumayang'aniridwa kumatha kupezeka pokhapokha powonjezera kuchuluka kwakukulu kwa etha ya cellulose yolemera pang'ono. Kukhuthala kwake sikudalira kwambiri kuchuluka kwa kumeta, ndipo kukhuthala kwakukulu kumafika ku kukhuthala komwe kukufunika, ndipo kuchuluka kowonjezera komwe kumafunika ndi kochepa, ndipo kukhuthala kumadalira mphamvu yokhuthala. Chifukwa chake, kuti pakhale kusinthasintha kwina, kuchuluka kwa etha ya cellulose (kuchuluka kwa yankho) ndi kukhuthala kwa yankho kuyenera kutsimikizika. Kutentha kwa gel kwa yankho kumachepanso motsatizana ndi kuwonjezeka kwa kuchuluka kwa yankho, ndi ma gels kutentha kwa chipinda atafika ku kuchuluka kwina. Kuchuluka kwa gelling kwa HPMC kumakhala kwakukulu kutentha kwa chipinda.
Kugwirizana kungasinthidwenso posankha kukula kwa tinthu tating'onoting'ono ndikusankha ma ether a cellulose okhala ndi madigiri osiyanasiyana osinthira. Chomwe chimatchedwa kusintha ndikuyambitsa kuchuluka kwina kwa magulu a hydroxyalkyl pa kapangidwe ka mafupa a MC. Mwa kusintha ma values osinthira ofanana a ma substituent awiri, ndiko kuti, ma values osinthira ofanana a DS ndi ms a magulu a methoxy ndi hydroxyalkyl omwe nthawi zambiri timanena. Zofunikira zosiyanasiyana za magwiridwe antchito a ether ya cellulose zitha kupezeka posintha ma values osinthira ofanana a ma substituent awiriwa.
Ubale pakati pa kusinthasintha ndi kusintha: kuwonjezera kwa cellulose ether kumakhudza momwe matope amagwiritsidwira ntchito madzi, kusintha chiŵerengero cha madzi ndi simenti kumawonjezera mphamvu, momwe mlingo umachulukira, momwe madzi amagwiritsidwira ntchito kwambiri.
Ma ether a cellulose omwe amagwiritsidwa ntchito popanga zipangizo zomangira zopangidwa ndi ufa ayenera kusungunuka mwachangu m'madzi ozizira ndikupereka kusinthasintha koyenera kwa dongosololi. Ngati apatsidwa mlingo winawake wochepetsera, amakhalabe flocculent ndi colloidal block, yomwe ndi chinthu chosakwanira kapena chapamwamba.
Palinso ubale wabwino pakati pa kusinthasintha kwa simenti ndi mlingo wa cellulose ether. Cellulose ether imatha kukulitsa kwambiri kukhuthala kwa matope. Mlingo ukakula, zotsatira zake zimakhala zoonekeratu. Yankho lamadzi la cellulose ether lamadzi lokhala ndi kukhuthala kwakukulu lili ndi thixotropy yambiri, yomwe ndi khalidwe lalikulu la cellulose ether. Mayankho amadzi a ma MC polymers nthawi zambiri amakhala ndi pseudoplastic ndi non-thixotropic fluidity pansi pa kutentha kwawo kwa gel, koma Newtonian flow properties pamlingo wotsika wa shear. Pseudoplasticity imawonjezeka ndi kulemera kwa molekyulu kapena kuchuluka kwa cellulose ether, mosasamala kanthu za mtundu wa cholowa m'malo ndi kuchuluka kwa cholowa m'malo. Chifukwa chake, ma cellulose ethers a kalasi yofanana ya kukhuthala, mosasamala kanthu za MC, HPMC, HEMC, nthawi zonse amawonetsa mphamvu zomwezo za rheological bola ngati kuchuluka ndi kutentha zikusungidwa nthawi zonse.
Ma gels opangidwa amapangidwa kutentha kukakwera, ndipo kuyenda kwa thixotropic kwambiri kumachitika. Ma ether a cellulose okhala ndi kuchuluka kwakukulu komanso kukhuthala kochepa amasonyeza thixotropy ngakhale pansi pa kutentha kwa gel. Katunduyu ndi wothandiza kwambiri pakusintha kusinthasintha ndi kutsika pomanga matope omangira. Apa tikuyenera kufotokoza kuti kukhuthala kwa cellulose ether kumakhala bwino, kusunga madzi kumakhala bwino, koma kukhuthala kwakukulu, kulemera kwa cellulose ether kumakhala kwakukulu, komanso kuchepa kofanana kwa kusungunuka kwake, komwe kumakhudza kwambiri kuchuluka kwa matope ndi magwiridwe antchito omanga. Kukhuthala kwakukulu, kukhuthala kumaonekera bwino pamatope, koma sikufanana kwathunthu. Kukhuthala pang'ono kwapakati ndi kotsika, koma ether yosinthidwa ya cellulose imakhala ndi magwiridwe antchito abwino pakukweza mphamvu ya matope onyowa. Ndi kuwonjezeka kwa kukhuthala, kusunga madzi kwa cellulose ether kumakula. 4. Kuchedwa kwa ether ya cellulose
Kuchedwa kwa ether ya cellulose: Ntchito yachitatu ya ether ya cellulose ndikuchedwetsa njira yothira madzi ya simenti. Ether ya cellulose imapatsa matope zinthu zosiyanasiyana zothandiza, komanso imachepetsa kutentha kwa simenti koyambirira komanso imachedwetsa njira yothira madzi ya simenti. Izi sizoyenera kugwiritsa ntchito matope m'malo ozizira. Kuchedwa kumeneku kumachitika chifukwa cha kuyamwa kwa mamolekyu a ether ya cellulose pazinthu zothira madzi monga CSH ndi ca(OH)2. Chifukwa cha kuchuluka kwa kukhuthala kwa yankho la pore, ether ya cellulose imachepetsa kuyenda kwa ma ayoni mu yankho, motero imachedwetsa njira yothira madzi.
Nthawi yotumizira: Feb-04-2023