Ọrụ dị mkpa nke cellulose ether na ngwa ngwa agwakọta agwakọta:
N'ime ngwa agha agwakọtara agwakọta, ọnụ ọgụgụ cellulose ether agbakwunyere dị ntakịrị, mana ọ nwere ike melite arụmọrụ ngwa ngwa mmiri, ịrụ ọrụ ngwa ngwa bụ nnukwu mgbakwunye. Nhọrọ ezi uche dị na ya nke ụdị dị iche iche, viscosity dị iche iche, nha nha dị iche iche, ogo viscosity dị iche iche na itinye ego nke cellulose ether
N'ime ngwa agha agwakọtara agwakọta, ọnụ ọgụgụ cellulose ether agbakwunyere dị ntakịrị, mana ọ nwere ike melite arụmọrụ ngwa ngwa mmiri, ịrụ ọrụ ngwa ngwa bụ nnukwu mgbakwunye. Nhọrọ ezi uche dị na ya nke cellulose ether dị iche iche, dị iche iche viscosity, dị iche iche urughuru size, dị iche iche viscosity ogo na mgbakwunye ego nwere mmetụta dị mma na mma nke akọrọ ngwa agha Njirimara. Ka ọ dị ugbu a, ọtụtụ ngwa agha masonry na plasta adịghị arụ ọrụ njide mmiri na-adịghị mma, na nkewa mmiri ga-eme mgbe nkeji ole na ole guzoro.
Njide mmiri bụ ọrụ dị mkpa nke methyl cellulose ether, kamakwa ọtụtụ ndị na-emepụta ngwa agha akọrọ nke ụlọ, karịsịa na mpaghara ndịda nke ndị na-emepụta okpomọkụ dị elu na-eche banyere arụmọrụ ahụ. Ihe ndị na-emetụta mmetụta njigide mmiri nke ngwa ngwa akọrọ gụnyere ọnụọgụ MC, viscosity MC, mma nke uru na okpomọkụ.
Cellulose ether bụ polymer sịntetik mere cellulose eke dị ka akụrụngwa site na mgbanwe kemịkalụ. Cellulose ether bụ ihe sitere na cellulose eke, mmepụta cellulose ether na polymer sịntetik dị iche, ihe kachasị mkpa bụ cellulose, ogige polymer eke. N'ihi ihe dị iche iche nke usoro cellulose eke, cellulose n'onwe ya enweghị ike imeghachi omume na onye na-emepụta ihe. Otú ọ dị, mgbe ọgwụgwọ nke ọzịza gị n'ụlọnga, ike hydrogen agbụ n'etiti molekụla agbụ na n'ime yinye e bibiri, na ọrụ nke hydroxyl otu wepụtara n'ime alkali cellulose na mmeghachi omume ike, na cellulose ether nwetara site mmeghachi omume nke ETHERifying gị n'ụlọnga - Otu OH n'ime -OR otu.
Njirimara nke cellulose ethers na-adabere n'ụdị, ọnụ ọgụgụ na nkesa nke ndị nọchiri anya ya. Nkewa nke cellulose ether na-adaberekwa n'ụdị ihe ngbanwe, ogo nke etherification, solubility na ngwa metụtara ya nwere ike nkewa. Dị ka ụdị ihe ndị na-anọchi anya na agbụ molecular, enwere ike kewaa ya n'ime otu ether na ngwakọta ether. A na-ejikarị MC eme ihe dị ka otu ether, ebe HPMC bụ ether agwakọta. Methyl cellulose ether MC bụ eke cellulose glucose unit na hydroxyl methoxide dochie ngwaahịa nhazi usoro bụ [COH7O2 (OH) 3-H (OCH3) H] X, hydroxypropyl methyl cellulose ether HPMC bụ unit na hydroxyl akụkụ nke hydroxyl. methoxide dochie hydroxypropyl, akụkụ ọzọ nke ngwaahịa a na-anọchi hydroxypropyl, Usoro nhazi bụ [C6H7O2 (OH) 3-MN (OCH3) M [OCH2CH (OH) CH3] N] X na hydroxyethyl methyl cellulose ether HEMC, nke bụ. ọtụtụ ebe na-ere na ahịa.
Site na solubility nwere ike kewaa n'ime ụdị ionic na ndị na-abụghị ionic. Mmiri-soluble na-abụghị ionic cellulose ether bụ tumadi mejupụtara alkyl ether na hydroxyl alkyl ether abụọ usoro iche iche. A na-eji Ionic CMC eme ihe na ncha sịntetik, textile, mbipụta, nri na nrigbu mmanụ ala. Ndị na-abụghị ionic MC, HPMC, HEMC na ndị ọzọ a na-ejikarị eme ihe ụlọ, mkpuchi latex, ọgwụ, kemistri kwa ụbọchị na akụkụ ndị ọzọ. Dị ka ihe na-eme ka ihe na-eme ka ọ sie ike, onye na-ejide mmiri, stabilizer, dispersant, onye na-emepụta ihe nkiri.
Cellulose ether mmiri na-ejigide: na mmepụta nke ihe owuwu ụlọ, karịsịa akọrọ ngwa agha, cellulose ether na-arụ ọrụ na-apụghị dochie anya, karịsịa na mmepụta nke pụrụ iche ngwa agha (modified ngwa agha), kamakwa akụkụ dị mkpa. Ọrụ dị mkpa nke mmiri-soluble cellulose ether na ngwa agha tumadi nwere akụkụ atọ, otu bụ magburu onwe njigide mmiri ike, nke abụọ bụ mmetụta nke ngwa agha agbanwe agbanwe na thixotropy, na nke atọ bụ mmekọrịta na ciment. Cellulose ether mmiri na-ejigide, dabere na isi nke hydroscopicity, mejupụtara nke ngwa agha, ngwa agha oyi akwa ọkpụrụkpụ, ngwa agha mmiri chọrọ, condensation ihe condensation oge. Njide mmiri nke cellulose ether sitere na solubility na akpịrị ịkpọ nkụ nke cellulose ether n'onwe ya. A maara nke ọma na agbụ mkpụrụ ndụ cellulose, n'agbanyeghị na ha nwere ọnụ ọgụgụ buru ibu nke otu OH nwere mmiri mmiri, na-adịghị edozi na mmiri n'ihi nhazi ha nke ukwuu. Ike hydration nke otu hydroxyl naanị ezughị iji kwụọ ụgwọ maka njikọ njikọ hydrogen intermolecular siri ike na ndị agha van der Waals. Mgbe a na-ewebata ihe ndị nọchiri anya n'ime agbụ molekụla, ọ bụghị naanị ihe ndị na-anọchi anya na-emebi yinye hydrogen, kamakwa a na-agbaji njikọ interchain hydrogen n'ihi ịgbanye ihe ndị nọchiri anya n'etiti agbụ ndị dị n'akụkụ. Ka ibu ihe ndị nọchiri anya ya, ka ebe dị anya n'etiti ụmụ irighiri ihe dị. Ka ukwuu mbibi nke hydrogen bond mmetụta, cellulose lattice mgbasa, ihe ngwọta n'ime cellulose ether na-aghọ mmiri soluble, e guzobere elu viscosity ngwọta. Ka okpomọkụ na-ebili, hydration nke polymer na-ebelata na mmiri dị n'etiti agbụ na-apụ apụ. Mgbe mmetụta mmiri na-ekpo ọkụ zuru ezu, ụmụ irighiri ihe ndị ahụ na-amalite ịgbakọta na gel na-apịaji na netwọk nke akụkụ atọ.
Ihe ndị na-emetụta njide mmiri nke ngwa agha gụnyere cellulose ether viscosity, usoro onunu ogwu, urughuru mma na okpomọkụ ọrụ.
Ka viscosity nke cellulose ether dị ukwuu, otú ahụ ka ọrụ njigide mmiri dị mma. Viscosity bụ oke dị mkpa nke arụmọrụ MC. Ka ọ dị ugbu a, ndị na-emepụta MC dị iche iche na-eji ụzọ na ngwa dị iche iche tụọ viscosity nke MC. Ụzọ ndị bụ isi gụnyere Haake Rotovisko, Hoppler, Ubbelohde na Brookfield. Maka otu ngwaahịa ahụ, nsonaazụ nke viscosity tụrụ site na ụzọ dị iche iche dị nnọọ iche, ụfọdụ bụ ọbụna ọtụtụ ọdịiche. Ya mere, mgbe ị na-atụnyere viscosity, a ghaghị ime ya n'etiti otu usoro ule, gụnyere okpomọkụ, rotor, wdg.
N'ikwu okwu n'ozuzu, ka viscosity dị elu, ka mma na-ejide mmiri. Otú ọ dị, ka elu viscosity bụ, elu nke molekụla arọ nke MC bụ, na mgbasa arụmọrụ ga-ebelata kwekọrọ ekwekọ, nke nwere mmetụta ọjọọ na ike na ewu arụmọrụ nke ngwa agha. Ihe dị elu nke viscosity, otú ahụ ka ọ na-apụta ìhè na mmetụta nke ngwa ngwa, ma ọ bụghị nke kwekọrọ na mmekọrịta ahụ. N'ịdị elu nke viscosity, ngwa agha mmiri ga-adịkwu nro, ma ihe owuwu ahụ, arụ ọrụ nke scraper na-egbuke egbuke na nnukwu nchikota na ihe isi. Mana ọ naghị enye aka ịbawanye ike nhazi nke ngwa agha mmiri. N'oge a na-ewu ụlọ, arụ ọrụ mgbochi sag abụghị ihe doro anya. N'ụzọ megidere nke ahụ, ụfọdụ viscosity dị ala mana emegharịrị methyl cellulose ethers nwere ọmarịcha arụmọrụ n'ịkwalite ike nhazi nke ngwa agha mmiri.
A na-agbakwunye cellulose ether na ngwa agha ahụ, na-arụ ọrụ nke ọma na-ejigide mmiri, na-eme ka viscosity dị elu, na-arụ ọrụ njide mmiri dị mma.
N'ihi na urughuru size, mma urughuru, mma na mmiri njigide. Nnukwu ahụ nke cellulose ether kọntaktị na mmiri, n'elu ozugbo igbari na-etolite a jel kechie ihe iji gbochie mmiri ụmụ irighiri ịnọgide na-abanye n'ime, mgbe ụfọdụ ogologo oge na-akpali akpali enweghị ike evenly gbasasịrị etisasịwo, guzobe a apịtị flocculent ngwọta ma ọ bụ. agglomerate. Solubility nke cellulose ether bụ otu n'ime ihe ndị na-ahọrọ cellulose ether. Ịdị mma bụkwa ihe ngosi arụmọrụ dị mkpa nke methyl cellulose ether. MC maka ngwa agha akọrọ chọrọ ntụ ntụ, ọdịnaya mmiri dị ala, yana ịdị mma nke 20% ~ 60% nha nha na-erughị 63um. Ịdị mma na-emetụta solubility nke methyl cellulose ether. Oke MC na-abụkarị granular na enwere ike ịgbaze ngwa ngwa n'ime mmiri na-enweghị agglomerating, mana mgbasa mgbasa na-adị ngwa ngwa, yabụ na ọ naghị adabara iji ngwa ngwa akọrọ. N'ime ngwa agha akọrọ, MC na-agbasasị n'etiti mkpokọta, ihe ndị dị mma na ihe simenti dị ka ciment, na naanị ntụ ntụ nke dị mma nwere ike izere ịchịkọta methyl cellulose ether mgbe ị na-agwakọta mmiri. Mgbe MC gbakwunyere mmiri iji gbazee agglomerate, ọ na-esiri ike ịgbasa na igbari ya. MC nwere ezigbo mma ọ bụghị naanị mkpofu, kamakwa ọ na-ebelata ike ngwa agha mpaghara. Mgbe a na-arụ ngwa ngwa akọrọ dị otú ahụ n'ebe buru ibu, a na-ebelata ọsọ nke ngwa ngwa akọrọ na mpaghara, na-ebute mgbawa nke oge ọgwụgwọ dị iche iche kpatara. Maka ngwa agha ịgbasa igwe, n'ihi obere oge ịgwakọta, ịdị mma dị elu.
Ịdị mma nke MC nwekwara mmetụta ụfọdụ na njide mmiri ya. N'ikwu okwu n'ozuzu, maka methyl cellulose ether nwere otu viscosity ma dị iche iche dị mma, nke ọma mmetụta njide mmiri dị mma n'okpuru otu ego mgbakwunye.
Njide mmiri nke MC na-ejikọta ya na okpomọkụ ejiri mee ihe, na njide mmiri nke methyl cellulose ether na-ebelata na ịrị elu okpomọkụ. Ma n'ezie ihe ngwa ngwa, ọtụtụ gburugburu nke akọrọ ngwa agha mgbe ga-abụ na elu okpomọkụ (elu 40 degrees) n'okpuru ọnọdụ nke ewu na-ekpo ọkụ mkpụrụ, dị ka okpomọkụ insolation nke mputa mgbidi putty plasta, nke na-emekarị accelerated na solidification nke. simenti na akọrọ ngwa agha hardening. Mbelata nke ọnụ ọgụgụ njide mmiri na-eduga n'echiche doro anya na ma nrụpụta na nkwụsi ike na-emetụta. N'ọnọdụ a, ibelata mmetụta nke ihe okpomọkụ na-aghọ nke dị oke egwu. Ọ bụ ezie na a na-ahụta mgbakwunye nke methyl hydroxyethyl cellulose ether dị ka onye na-ebute ụzọ na mmepe teknụzụ, ịdabere na ọnọdụ okpomọkụ ka ga-eduga na ike ọgwụgwụ nke ngwa ngwa akọrọ. Ọbụlagodi na mmụba nke usoro onunu ogwu methyl hydroxyethyl cellulose (usoro ọkọchị), ihe owuwu na nguzogide mgbawa enweghị ike igbo mkpa nke ojiji. Site na ụfọdụ ọgwụgwọ pụrụ iche nke MC, dị ka ịba ụba nke etherification, mmetụta njigide mmiri nke MC nwere ike ịnọgide na-enwe mmetụta dị mma n'okpuru okpomọkụ dị elu, ka o wee nwee ike inye ọrụ ka mma n'okpuru ọnọdụ siri ike.
Na mgbakwunye, cellulose ether ndim na thixotropy: cellulose ether edinam nke abụọ - ndim na-adabere: cellulose ether polymerization ogo, ngwọta ngwọta, shiee ọnụego, okpomọkụ na ọnọdụ ndị ọzọ. Ngwongwo gelation nke ngwọta bụ ihe pụrụ iche na alkyl cellulose na ihe ndị gbanwetụrụ. Njirimara Gelation metụtara ogo nke nnọchi, ntinye ngwọta na mgbakwunye. Maka ihe nrụpụta hydroxyl alkyl gbanwetụrụ, ihe gel na-emetụtakwa ogo mgbanwe hydroxyl alkyl. N'ihi na ngwọta ịta nke ala viscosity MC na HPMC nwere ike kwadebere 10% -15% ịta ngwọta, ọkara viscosity MC na HPMC nwere ike kwadebere 5% -10% ngwọta, na elu viscosity MC na HPMC nwere ike kwadebere 2% -3. % ngwọta, na-emekarị cellulose ether viscosity grading bụkwa 1%-2% ngwọta na ọkwa. Elu molecular arọ cellulose ether thickener arụmọrụ, otu ntinye nke ngwọta, dị iche iche molekul arọ polymers nwere dị iche iche viscosity, viscosity na molekụla arọ nwere ike igosipụta dị ka ndị a, [η] = 2.92 × 10-2 (DPn) 0.905, DPn bụ nkezi. polymerization ogo nke elu. Eter cellulose dị arọ dị ala iji gbakwunye ihe iji nweta viscosity ebumnuche. Ya viscosity bụ obere dabere na shiee ọnụego, elu viscosity iji nweta lekwasịrị viscosity, ego dị mkpa iji tinye obere, viscosity dabere na ndim arụmọrụ. Ya mere, iji nweta otu ihe na-agbanwe agbanwe, a ghaghị ijide n'aka na ether cellulose ether (ntụkwasị uche nke ngwọta) na viscosity ngwọta ga-ekwe nkwa. Okpomọkụ gelation nke ihe ngwọta na-ebelata n'ahịrị na mmụba nke ntinye nke ngwọta, na gelation mere na ụlọ okpomọkụ mgbe ọ ruru otu ntinye uche. HPMC nwere mkpokọta gelation dị elu na ụlọ okpomọkụ.
A pụkwara imezi nkwụsi ike site n'ịhọrọ nha nha na cellulose ethers nwere ogo dị iche iche nke mgbanwe. Ihe a na-akpọ mgbanwe bụ iwebata hydroxyl alkyl otu n'ime ogo ụfọdụ nke nnọchi na nhazi ọkpụkpụ nke MC. Site n'ịgbanwe ụkpụrụ ngbanwe nke ndị nnọchi anya abụọ ahụ, ya bụ, ụkpụrụ nnọchi DS na MS nke methoxy na otu hydroxyl. Ngwongwo dị iche iche nke cellulose ether chọrọ site n'ịgbanwe ụkpụrụ ngbanwe nke ụdị abụọ nke nnọchi.
Mmekọrịta dị n'etiti nkwụsi ike na mgbanwe: mgbakwunye cellulose ether na-emetụta mmiri oriri nke ngwa agha, na-agbanwe mmiri na-ekekọta mmiri nke mmiri na ciment, nke bụ mmetụta na-egbuke egbuke. Nke dị elu nke usoro onunu ogwu, ka oriri mmiri na-abawanye.
Cellulose ethers eji eme ihe na-ewu ụlọ ntụ ntụ ga-agbaze ngwa ngwa na mmiri oyi ma nye usoro kwesịrị ekwesị. Ọ bụrụ na ọnụ ọgụgụ shear enyere ka na-efegharị efegharị na colloidal ọ bụ ngwaahịa na-adighi mma ma ọ bụ na-adịghị mma.
Enwekwara mmekọrịta dị mma nke linear n'etiti ciment slurry anọgidesi na usoro onunu ogwu nke cellulose ether, cellulose ether nwere ike dịkwuo viscosity nke ngwa agha, ukwuu na onunu ogwu, pụta ìhè mmetụta. Cellulose ether aqueous ngwọta na elu viscosity nwere elu thixotropy, nke bụ otu n'ime àgwà nke cellulose ether. Aqueous ngwọta nke MC ụdị polymers na-enwekarị pseudoplastic, na-abụghị thixotropic fluidity n'okpuru ha gel okpomọkụ, ma Newtonian eruba Njirimara na ala shiee ọnụego. Pseudoplasticity na-abawanye site na mmụba nke ịdị arọ molekụla ma ọ bụ itinye uche nke ether cellulose ma nweere onwe ya n'ụdị na ogo ngbanwe. Ya mere, cellulose ethers nke otu viscosity ọkwa, ma MC, HPMC ma ọ bụ HEMC, mgbe niile na-egosi otu rheological Njirimara ma ọ bụrụhaala na ịta na okpomọkụ na-anọgide na-adịgide adịgide. Mgbe okpomọkụ na-abawanye, a na-emepụta gel nhazi na oke thixotropic na-eme. Cellulose ethers nwere nnukwu itinye uche na viscosity dị ala na-egosipụta thixotropy ọbụna n'okpuru okpomọkụ gel. Ngwongwo a na-aba uru dị ukwuu maka owuwu ihe owuwu ụlọ iji mezie ihe ọ na-asọ na ihe na-asọpụta. Ọ dị mkpa ka a kọwaa ebe a na elu viscosity nke cellulose ether, mma njigide mmiri, ma elu nke viscosity, nke dị elu ikwu molekụla arọ nke cellulose ether, kwekọrọ ekwekọ Mbelata ya solubility, nke nwere mmetụta ọjọọ na ya. na ngwa agha ịta na ịrụ ọrụ ihe owuwu. Nke dị elu nke viscosity, otú ahụ ka ọ na-apụta ìhè nke ọma mmetụta nke ngwa agha, ma ọ bụghị mmekọrịta zuru oke. Ụfọdụ obere viscosity, ma ether cellulose gbanwetụrụ na imeziwanye ike nhazi nke ngwa agha mmiri na-arụ ọrụ nke ọma karị, na mmụba nke viscosity, cellulose ether mmiri na-ejigide mma.
Cellulose ether retardation: cellulose ether ọrụ nke atọ bụ igbu oge usoro hydration nke ciment. Cellulose ether na-enye ngwa agha nwere ihe bara uru dị iche iche, ma na-ebelata mmalite nke hydration okpomọkụ ntọhapụ nke ciment, na-egbu oge usoro hydration siri ike nke ciment. Nke a adịghị mma iji ngwa agha na mpaghara oyi. Ụdị mmetụta retarding a bụ cellulose ether molecule adsorption na CSH na Ca (OH) 2 ngwaahịa hydration kpatara, n'ihi mmụba nke viscosity ngwọta pore, cellulose ether na-ebelata ọrụ nke ion na ngwọta, si otú ahụ na-egbu oge usoro hydration. Ihe dị elu nke cellulose ether dị na ihe ịnweta gel gel, otú ahụ ka mmetụta nke igbu oge hydration pụta ìhè. Cellulose ether ọ bụghị nanị na-egbu oge nhazi ahụ, kamakwa usoro siri ike nke usoro ciment mortar. Mmetụta retarding nke cellulose ether na-adabere ọ bụghị nanị na ntinye ya na sistemụ ịnweta gel, kamakwa na usoro kemịkal. Ka ogo nke HEMC methylation dị elu, ka mma na-ebelata mmetụta nke cellulose ether. Mmetụta nkwụghachi azụ nke ngbanwe hydrophilic dị ike karịa nke mmiri na-abawanye ngbanwe. Ma viscosity nke cellulose ether enwechaghị mmetụta na hydration kinetics nke ciment.
Site na mmụba nke cellulose ether ọdịnaya, nhazi oge nke ngwa agha na-abawanye nke ukwuu. Oge ntọala mbụ nke ngwa agha nwere njikọ dị mma na ọdịnaya nke cellulose ether, na oge nhazi ikpeazụ nwere njikọ dị mma na ọdịnaya nke cellulose ether. Anyị nwere ike ijikwa oge arụ ọrụ nke ngwa agha site n'ịgbanwe usoro nke cellulose ether.
N'ịchịkọta, na ngwa ngwa agwakọta dị njikere, cellulose ether na-ekere òkè na njide mmiri, na-eme ka ọ dị arọ, na-egbu oge ike hydration ciment, na-emeziwanye ihe owuwu ụlọ. Ikike njide mmiri dị mma na-eme ka hydration ciment zuo oke, nwere ike melite viscosity mmiri nke ngwa agha mmiri, melite ike njikọ nke ngwa agha, oge mgbanwe. Ịgbakwunye cellulose ether na ngwa agha ịgbasa igwe nwere ike imeziwanye ịgbasa ma ọ bụ ịgbapụta arụmọrụ yana ike nhazi nke ngwa agha. Ya mere, a na-eji cellulose ether eme ihe dị ka ihe mgbakwunye dị mkpa na ngwa ngwa agwakọta.
Oge nzipu: Dec-17-2021