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Cellulose ether na ngwaahịa simenti

Cellulose ether na ngwaahịa simenti

Cellulose ether bụ ụdị mgbakwunye multipurpose nke enwere ike iji na ngwaahịa ciment. Akwụkwọ a na-ewebata njirimara kemịkalụ nke methyl cellulose (MC) na hydroxypropyl methyl cellulose (HPMC /) nke a na-ejikarị na ngwaahịa ciment, usoro na ụkpụrụ nke ngwọta net na isi njirimara nke ngwọta. A tụlere mbelata okpomọkụ gel thermal na viscosity na ngwaahịa ciment dabere na ahụmịhe mmepụta bara uru.

Isi okwu:cellulose ether; Methyl cellulose;Hydroxypropyl methyl cellulose; Gel na-ekpo ọkụ; viscosity

 

1. Nchịkọta

A na-eme cellulose ether (CE maka mkpụmkpụ) nke cellulose site na mmeghachi omume etherification nke otu ma ọ bụ ọtụtụ ndị na-emepụta ihe na-egweri akọrọ. Enwere ike kewaa CE n'ime ụdị ionic na ndị na-abụghị ionic, n'ime nke ụdị CE nke na-abụghị ionic n'ihi njirimara gel dị iche iche nke thermal na solubility, nguzogide nnu, nguzogide okpomọkụ, ma nwee ọrụ elu kwesịrị ekwesị. Enwere ike iji ya dị ka onye na-ejigide mmiri, onye nkwusioru, emulsifier, onye na-emepụta ihe nkiri, mmanu mmanu, nrapado na rheological. Ebe ndị mba ọzọ na-eri nri bụ mkpuchi latex, ihe ụlọ, mkpọ mmanụ na ihe ndị ọzọ. E jiri ya tụnyere mba ndị ọzọ, mmepụta na ntinye nke CE na-agbaze mmiri ka na-amalite. Site na nkwalite ahụike ndị mmadụ na mmata gburugburu ebe obibi. CE nke na-agbaze mmiri, nke na-adịghị njọ na physiology na-adịghị emerụ gburugburu ebe obibi, ga-enwe nnukwu mmepe.

N'ọhịa nke ụlọ ihe a na-ahọrọkarị CE bụ methyl cellulose (MC) na hydroxypropyl methyl cellulose (HPMC), nwere ike ji mee ihe dị ka agba, plasta, ngwa agha na simenti ngwaahịa plasticizer, viscosifier, mmiri njide gị n'ụlọnga, ikuku entraining gị n'ụlọnga na retarding gị n'ụlọnga. Ọtụtụ n'ime ụlọ ihe ụlọ ọrụ na-eji na nkịtị okpomọkụ, na-eji ọnọdụ ndị akọrọ mix ntụ ntụ na mmiri, na-erughị metụtara mgbasa e ji mara na-ekpo ọkụ jel e ji mara nke CE, ma na mechanized mmepụta nke ciment ngwaahịa na ndị ọzọ pụrụ iche okpomọkụ ọnọdụ, ndị a e ji mara nke. CE ga-arụ ọrụ zuru oke.

 

2. Chemical Njirimara nke CE

A na-enweta CE site n'ịgwọ cellulose site na usoro kemịkalụ na nke anụ ahụ. Dị ka dị iche iche chemical nnọchi Ọdịdị, na-emekarị nwere ike kewara n'ime: MC, HPMC, hydroxyethyl cellulose (HEC), wdg : Onye ọ bụla OA nwere isi Ọdịdị nke cellulose - dehydrated glucose. N'ime usoro nke imepụta CE, a na-ebu ụzọ kpoo eriri cellulose na ngwọta alkaline wee mesoo ya na ihe ndị na-eme ka ahụ dị ike. A na-asachapụ ngwaahịa mmeghachi omume fibrous ma kporie ya ka ọ bụrụ ntụ ntụ nke otu ịdị mma.

Usoro mmepụta nke MC na-eji naanị methane chloride dị ka onye na-emepụta ihe. Na mgbakwunye na iji methane chloride, mmepụta nke HPMC na-ejikwa propylene oxide nweta otu ndị na-anọchi anya hydroxypropyl. CE dị iche iche nwere ọnụego nnọchi methyl na hydroxypropyl dị iche iche, nke na-emetụta ndakọrịta organic na thermal jel nke ngwọta CE.

Ọnụ ọgụgụ nke nnọchi dị iche iche na dehydrated glucose structural nkeji nke cellulose nwere ike gosi site na pasent nke uka ma ọ bụ nkezi ọnụ ọgụgụ nke nnọchi otu (ie, DS - Degree nke nnọchi). Ọnụọgụ ndị nnọchi anya na-ekpebi njirimara ngwaahịa CE. Mmetụta nke nkezi ogo nke nnọchi na solubility nke ngwaahịa etherification bụ nke a:

(1) obere nnọchi ogo soluble na lye;

(2) ubé elu ogo nke nnọchi soluble na mmiri;

(3) elu ogo nke nnọchi etisasịwo na pola organic solvents;

(4) Ọkwa dị elu nke nnọchi agbazere na ihe mgbaze organic na-abụghị polar.

 

3. Usoro mgbasa nke CE

CE nwere ihe solubility pụrụ iche, mgbe okpomọkụ na-ebili n'otu okpomọkụ, ọ na-esighi ike na mmiri, ma n'okpuru okpomọkụ a, solubility ya ga-abawanye na mbelata nke okpomọkụ. CE na-agbaze n'ime mmiri oyi (na n'ọnọdụ ụfọdụ na ihe mgbaze organic kpọmkwem) site na usoro ọzịza na hydration. Ngwọta CE enweghị njedebe doro anya nke na-apụta na mgbaze nke nnu ion. Ntinye uche nke CE na-ejedebe na viscosity nke akụrụngwa mmepụta nwere ike ịchịkwa, yana dịgasị iche iche dabere na viscosity na ụdị kemịkalụ nke onye ọrụ chọrọ. Ngwọta ngwọta nke obere viscosity CE bụ n'ozuzu 10% ~ 15%, na elu viscosity CE na-ejedebe na 2% ~ 3%. Ụdị CE dị iche iche (dị ka ntụ ntụ ma ọ bụ n'elu mesoo ntụ ntụ ma ọ bụ granular) nwere ike imetụta otú e si akwadebe ihe ngwọta.

3.1 CE na-enweghị ọgwụgwọ elu

Ọ bụ ezie na CE na-agbaze na mmiri oyi, a ga-achụsasị ya kpamkpam n'ime mmiri ka ọ ghara ịgbakọta. N'ọnọdụ ụfọdụ, enwere ike iji igwekota ma ọ bụ olulu mmiri dị elu na mmiri oyi gbasasịa ntụ ntụ CE. Otú ọ dị, ọ bụrụ na a na-agbakwunye ntụ ntụ a na-adịghị edozi ozugbo na mmiri oyi na-enweghị mkpali nke ọma, nnukwu lumps ga-etolite. Isi ihe kpatara ịme achịcha bụ na ntụ ntụ CE adịghị mmiri kpamkpam. Mgbe naanị akụkụ nke ntụ ntụ na-agbaze, a ga-emepụta ihe nkiri gel, nke na-egbochi ntụ ntụ fọdụrụnụ ka ọ nọgide na-agbaze. Ya mere, tupu mgbasa, a ga-agbasasị akụkụ CE nke ọma ka o kwere mee. A na-ejikarị ụzọ mgbasa ozi abụọ ndị a.

3.1.1 Akọrọ mix mgbasa mgbasa

A na-ejikarị usoro a eme ihe na ngwaahịa ciment. Tupu ịtinye mmiri, gwakọta ntụ ntụ ndị ọzọ na ntụ ntụ CE nke ọma, nke mere na ihe ntụ ntụ CE ga-agbasasị. Ngwakọta kacha nta: ntụ ntụ ndị ọzọ: ntụ ntụ CE = (3 ~ 7): 1.

N'ime usoro a, a na-emecha mgbasa nke CE n'ime ala kpọrọ nkụ, na-eji ntụ ntụ ndị ọzọ dị ka ihe na-agbasasị akụkụ CE n'otu n'otu, iji zere njikọkọ nke ihe CE mgbe ị na-agbakwunye mmiri ma na-emetụta mgbasa ọzọ. Ya mere, mmiri ọkụ adịghị mkpa maka mgbasa, ma mgbasa ozi na-adabere na ntụ ntụ ntụ na ọnọdụ na-akpali akpali.

3.1.2 Usoro mgbasa mmiri ọkụ

(1) Nke mbụ 1/5 ~ 1/3 nke mmiri ọkụ chọrọ ka 90C dị n'elu, gbakwunye CE, wee mee ka ahụ ruo mgbe ihe niile na-ekpochapụ mmiri, na mmiri oyi ma ọ bụ mmiri oyi gbakwunyere iji belata okpomọkụ nke mmiri oyi. Ngwọta, ozugbo ruru ogo mgbasa CE, ntụ ntụ malitere hydrate, viscosity mụbara.

(2) Ị nwekwara ike kpoo mmiri niile, wee tinye CE ka ọ na-akpali mgbe ị na-ajụ oyi ruo mgbe hydration zuru ezu. Iju oyi zuru oke dị ezigbo mkpa maka hydration zuru oke nke CE yana imepụta viscosity. N'ihi na ezigbo viscosity, MC ngwọta kwesịrị mma ka 0 ~ 5 ℃, mgbe HPMC naanị kwesịrị ka mma ka 20 ~ 25 ℃ ma ọ bụ n'okpuru. Ebe ọ bụ na hydration zuru ezu chọrọ nju oyi zuru oke, a na-ejikarị ngwọta HPMC eme ihe ebe enweghị ike iji mmiri oyi: dịka ozi ahụ si kwuo, HPMC nwere obere mbelata okpomọkụ karịa MC na okpomọkụ dị ala iji nweta otu viscosity. Ọ dị mma ịmara na usoro ịgbasa mmiri na-ekpo ọkụ na-eme ka ụmụ irighiri ihe CE gbasaa n'otu oge na oke okpomọkụ, mana ọ nweghị ihe edoziri n'oge a. Iji nweta ngwọta nwere ụfọdụ viscosity, ọ ga-adị mma ọzọ.

3.2 Elu mesoro ntụ ntụ CE nke na-ekesa

N'ọtụtụ ọnọdụ, CE achọrọ ka ọ nwee njirimara hydration nke nwere ike ịgbasa yana ngwa ngwa (nke na-emepụta viscosity) na mmiri oyi. A na-esighi ike na mmiri oyi ruo nwa oge ka emechara ọgwụgwọ kemịkalụ pụrụ iche, nke na-ahụ na mgbe agbakwunyere CE na mmiri, ọ gaghị etolite viscosity doro anya ozugbo enwere ike gbasasịa n'okpuru ọnọdụ ike shii dị obere. "Oge igbu oge" nke nhazi hydration ma ọ bụ viscosity bụ nsonaazụ nke nchikota ogo nke ọgwụgwọ elu, okpomọkụ, pH nke usoro, na ntinye ngwọta CE. A na-ebelatakarị igbu oge nke hydration na ọkwa dị elu, okpomọkụ, na ọkwa pH. N'ozuzu, Otú ọ dị, a naghị atụle ntinye nke CE ruo mgbe ọ ruru 5% (oke oke mmiri).

Maka nsonaazụ kacha mma na hydration zuru oke, ekwesịrị ịkpali elu CE nke a na-emeso ya maka nkeji ole na ole n'okpuru ọnọdụ nnọpụiche, yana pH sitere na 8.5 ruo 9.0, ruo mgbe enwere ike iru viscosity kachasị (na-abụkarị nkeji 10-30). Ozugbo pH gbanwere na isi (pH 8.5 ruo 9.0), elu nke CE na-agbaze kpamkpam na ngwa ngwa, na ngwọta nwere ike kwụsie ike na pH 3 ruo 11. Otú ọ dị, ọ dị mkpa iburu n'obi na imezi pH nke nnukwu ịta ahụhụ slurry. ga-eme ka viscosity dị elu maka ịgbapụta na ịwụsa. Ekwesịrị imezi pH mgbe emechara slurry ahụ na ntinye uche achọrọ.

Iji chịkọta, usoro mgbasa nke CE gụnyere usoro abụọ: mgbasa nke anụ ahụ na mgbasa kemịkalụ. Isi ihe bụ ịgbasa irighiri CE na ibe ya tupu mgbasa, ka ịzenarị agglomeration n'ihi nnukwu viscosity n'oge mgbasa nke obere okpomọkụ, nke ga-emetụta mgbasa ọzọ.

 

4. Njirimara nke CE ngwọta

Ụdị dị iche iche nke mmiri mmiri CE ga-agbaze na okpomọkụ ha kpọmkwem. Gel na-agbanwe kpamkpam ma mepụta ngwọta mgbe ọ dị jụụ ọzọ. The reversible thermal gelation nke CE pụrụ iche. N'ọtụtụ ngwaahịa ciment, isi ojiji nke viscosity nke CE na njigide mmiri kwekọrọ na ihe mmanu mmanu, na viscosity na gel okpomọkụ nwere mmekọrịta kpọmkwem, n'okpuru gel okpomọkụ, na-ebelata okpomọkụ, elu viscosity nke CE, ka mma na-arụ ọrụ njigide mmiri kwekọrọ.

Nkọwa nke ugbu a maka ihe ngosi gel bụ nke a: na usoro mgbasa, nke a yiri

Mkpụrụ ndụ polymer nke eri na-ejikọta na oyi akwa molecular mmiri, na-ebute ọzịza. Mkpụrụ ndụ mmiri na-arụ ọrụ dị ka mmanụ na-ete mmanụ, nke nwere ike ịwepụ agbụ dị ogologo nke mkpụrụ ndụ polymer, nke mere na ngwọta ahụ nwere njirimara nke mmiri viscous nke dị mfe ịwụfu. Mgbe okpomọkụ nke ngwọta na-abawanye, polymer cellulose ji nwayọọ nwayọọ na-efunahụ mmiri na viscosity nke ngwọta na-ebelata. Mgbe oghere gel ruru, polymer na-aghọ mmiri kpamkpam, na-eme ka njikọ dị n'etiti polymers na nhazi nke gel: ike nke gel na-anọgide na-abawanye ka okpomọkụ na-anọgide n'elu ebe gel.

Ka ihe ngwọta ahụ dị jụụ, gel na-amalite ịtụgharị na viscosity na-ebelata. N'ikpeazụ, viscosity nke ngwọta jụrụ oyi na-alaghachi na mbido okpomọkụ nke mbụ ma na-abawanye na mbelata nke okpomọkụ. Enwere ike ime ka ngwọta ya dị jụụ ruo uru viscosity mbụ ya. Ya mere, usoro Gel thermal nke CE na-agbanwe agbanwe.

Ọrụ bụ isi nke CE na ngwaahịa ciment dị ka viscosifier, plasticizer na onye na-ejigide mmiri, yabụ otu esi ejikwa viscosity na gel okpomọkụ aghọwo ihe dị mkpa na ngwaahịa ciment na-ejikarị ebe okpomọkụ gel mbụ ya n'okpuru akụkụ nke usoro, ya mere na okpomọkụ dị ala, ka viscosity dị elu, otú ahụ ka mmetụta nke njide mmiri viscosifier pụta ìhè. Nsonaazụ nnwale nke ahịrị imepụta bọọdụ simenti extrusion na-egosikwa na ọ̀tụ̀tụ̀ ikpo ọkụ ihe dị n'okpuru otu ọdịnaya nke CE, ka mma viscosification na njigide mmiri dị mma. Dị ka simenti simenti bụ nnọọ mgbagwoju anya nke anụ ahụ na kemịkal ihe onwunwe, e nwere ọtụtụ ihe na-emetụta mgbanwe nke CE gel okpomọkụ na viscosity. Na mmetụta nke dị iche iche Taianin na-emekarị na ogo abụghị otu, ya mere ngwa bara uru chọpụtakwara na mgbe agwakọta usoro ciment, kpọmkwem ebe okpomọkụ gel nke CE (ya bụ, gluu na njigide mmiri na-ebelata bụ nke doro anya na okpomọkụ a. ) dị ala karịa gel okpomọkụ nke ngwaahịa ahụ gosipụtara, ya mere, na nhọrọ nke ngwaahịa CE ka ị buru n'uche ihe ndị na-eme ka okpomọkụ jel daa. Ihe ndị a bụ isi ihe anyị kwenyere na-emetụta viscosity na gel okpomọkụ nke CE ngwọta na ngwaahịa ciment.

4.1 Mmetụta nke uru pH na viscosity

MC na HPMC bụ ndị na-abụghị ionic, ya mere viscosity nke ngwọta karịa viscosity nke eke ionic gluu nwere a wider nso nke DH kwụsie ike, ma ọ bụrụ na pH uru karịa nso nke 3 ~ 11, ha ga-eji nwayọọ nwayọọ belata viscosity na a. elu okpomọkụ ma ọ bụ na nchekwa ruo ogologo oge, karịsịa elu viscosity ngwọta. Viscosity nke ngwọta ngwaahịa CE na-ebelata na acid siri ike ma ọ bụ ihe ngwọta siri ike, nke bụ n'ihi akpịrị ịkpọ nkụ nke CE nke isi na acid kpatara. Ya mere, viscosity nke CE na-agbadakarị ruo n'ókè ụfọdụ na mpaghara alkaline nke ngwaahịa ciment.

4.2 Mmetụta nke ọkụ ọkụ na-akpali akpali na usoro gel

A ga-emetụta ọnọdụ okpomọkụ nke ebe gel site na ngwakọta nke ọkụ ọkụ na-akpali akpali. Nnukwu ọsọ na-akpali akpali na kpo oku ngwa ngwa ga-abawanye okpomọkụ nke gel nke ukwuu, nke dị mma maka ngwaahịa ciment kpụrụ site na ngwakọta igwe.

4.3 Mmetụta nke itinye uche na gel na-ekpo ọkụ

Ịba ụba nke ngwọta na-ebelatakarị okpomọkụ gel, na isi ihe gel nke obere viscosity CE dị elu karịa nke elu viscosity CE. Dị ka DOW's METHOCEL A

A ga-ebelata okpomọkụ gel site na 10 ℃ maka mmụba 2% ọ bụla na ntinye nke ngwaahịa ahụ. Mmụba 2% na ntinye nke ụdị F ga-ebelata okpomọkụ gel site na 4 ℃.

4.4 Mmetụta nke mgbakwunye na gelation thermal

N'ihe gbasara ihe owuwu ụlọ, ọtụtụ ihe bụ nnu inorganic, nke ga-enwe mmetụta dị ukwuu na gel okpomọkụ nke CE ngwọta. Dabere na mgbakwunye na-eme ihe dị ka coagulant ma ọ bụ solubilizing, ụfọdụ mgbakwunye nwere ike ịbawanye okpomọkụ gel thermal nke CE, ebe ndị ọzọ nwere ike ibelata thermal gel okpomọkụ nke CE: dịka ọmụmaatụ, ethanol na-eme ka mgbaze, PEG-400 (polyethylene glycol) , anediol, wdg, nwere ike ịbawanye ebe gel. Nnu, glycerin, sorbitol na ihe ndị ọzọ ga-ebelata ebe gel, ndị na-abụghị ionic CE n'ozuzu agaghị ebuli ya n'ihi ion metal polyvalent, mana mgbe ntinye electrolyte ma ọ bụ ihe mgbaze ndị ọzọ gafere oke, ngwaahịa CE nwere ike tinye nnu na ya. Ngwọta, nke a bụ n'ihi asọmpi nke electrolytes na mmiri, na-ebute mbelata hydration nke CE, Nnu nke ngwọta nke ngwaahịa CE na-adịkarị elu karịa nke ngwaahịa Mc, na nnu dị iche iche dịtụ iche. HPMC dị iche iche.

Ọtụtụ ihe ndị dị na ngwaahịa ciment ga-eme ka ntụpọ gel nke CE dobe, yabụ nhọrọ nke mgbakwunye kwesịrị iburu n'uche na nke a nwere ike ibute isi gel na viscosity nke CE mgbanwe.

 

5.Mkpebi

(1) cellulose ether bụ eke cellulose site etherification mmeghachi omume, nwere isi structural unit nke dehydrated glucose dehydrated, dị ka ụdị na ọnụ ọgụgụ nke substituent otu na ya nnọchi ọnọdụ na nwere dị iche iche Njirimara. Enwere ike iji ether na-abụghị ionic dị ka MC na HPMC dị ka viscosifier, onye na-ejigide mmiri, onye na-emepụta ikuku na ihe ndị ọzọ a na-ejikarị eme ihe na ngwaahịa ụlọ.

(2) CE nwere solubility pụrụ iche, na-emepụta ngwọta na ụfọdụ okpomọkụ (dị ka gel okpomọkụ), na-akpụ siri ike jel ma ọ bụ siri ike urughuru ngwakọta na jel okpomọkụ. Isi mgbasa ụzọ bụ akọrọ Ịgwakọta dispersion usoro, mmiri ọkụ dispersion usoro, wdg, na ciment ngwaahịa a na-ejikarị bụ akọrọ Ịgwakọta dispersion usoro. Isi ihe bụ ịgbasa CE nke ọma tupu ọ gbazee, na-eme ihe ngwọta na obere okpomọkụ.

(3) Ngwọta ngwọta, okpomọkụ, pH uru, chemical Njirimara nke mgbakwunye na mkpali ọnụego ga-emetụta jel okpomọkụ na viscosity nke CE ngwọta, karịsịa ciment ngwaahịa bụ inorganic nnu ngwọta na alkaline gburugburu ebe obibi, na-emekarị belata gel okpomọkụ na viscosity nke CE ngwọta. , na-eweta mmetụta ọjọọ. Ya mere, dị ka njirimara CE si dị, nke mbụ, ekwesịrị iji ya na obere okpomọkụ (n'okpuru gel okpomọkụ), na nke abụọ, ekwesịrị iburu n'uche mmetụta nke mgbakwunye.


Oge nzipu: Jan-19-2023
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