Focus on Cellulose ethers

Ihe dị iche n'etiti HPMC na MC, HEC, CMC

Cellulose na-arụkarị ọrụ atọ nke ịgbakọ, idebe mmiri na ịrụ n'ime ngwa ngwa na agba.

Ọkpụkpụ: Enwere ike ịgbatị cellulose ka ọ kwụsịtụ ma mee ka ngwọta ya bụrụ otu elu na ala, ma guzogide ịda mbà n'obi.

Njide mmiri: mee ka ngwa agha na agba ya nwayọ nwayọ, ma nyere ihe ndị dị ka ash na calcium aka imeghachi omume n'okpuru mmiri.

Mwube: Cellulose nwere mmetụta mmanu mmanu, nke nwere ike ime ka ngwa agha na mkpuchi nwere ezigbo ihe owuwu.

1. Methyl cellulose (MC)

Mgbe ejiri alkali mesoo owu a nụchara anụcha, a na-emepụta cellulose ether site na mmeghachi omume nke methane chloride dị ka onye na-emepụta ihe.N'ozuzu, ogo nke nnọchi bụ 1.6 ~ 2.0, na solubility dịkwa iche na ọkwa dị iche iche nke nnọchi.Ọ bụ nke cellulose ether na-abụghị ionic.

(1) Methylcellulose na-agbaze na mmiri oyi, ọ ga-esikwa ike igbari na mmiri ọkụ.Ihe ngwọta ya na-edozi ahụ kwụsiri ike na pH = 3 ~ 12.Ọ nwere ezigbo ndakọrịta na starch, guar gum, wdg na ọtụtụ surfactants.Mgbe okpomọkụ na-erute okpomọkụ gelation, gelation na-eme.

(2) Njide mmiri nke methyl cellulose na-adabere na ego mgbakwunye ya, viscosity, urughuru mma na mgbasa ozi.N'ozuzu, ọ bụrụ na ego mgbakwunye buru ibu, ịdị mma dị ntakịrị, na viscosity dị ukwuu, ọnụ ọgụgụ njide mmiri dị elu.N'ime ha, ọnụ ọgụgụ nke mgbakwunye na-enwe mmetụta kachasị ukwuu na njide mmiri, na ọkwa nke viscosity adịghị adabere kpọmkwem na ọkwa nke njide mmiri.The mgbasa ọnụego tumadi na-adabere n'ókè nke elu mgbanwe nke cellulose ahụ na urughuru fineness.N'ime cellulose ethers dị n'elu, methyl cellulose na hydroxypropyl methyl cellulose nwere ọnụ ọgụgụ njide mmiri dị elu.

(3) Mgbanwe na okpomọkụ ga-emetụta oke njide mmiri nke methyl cellulose.N'ozuzu, ka okpomọkụ dị elu, na-akawanye njọ njigide mmiri.Ọ bụrụ na okpomọkụ nke ngwa agha gafere 40 Celsius, njide mmiri nke methyl cellulose ga-ebelata nke ukwuu, na-emetụta nrụnye ngwa ngwa.

(4) Methyl cellulose nwere mmetụta dị ịrịba ama na arụ ọrụ na adhesion nke ngwa agha.“Adhesion” ebe a na-ezo aka na ike nrapado a na-enwe n'etiti ngwa ngwa onye ọrụ na mkpụrụ mgbidi, ya bụ, nkwụsi ike nke ngwa agha ahụ.Nchikota dị elu, nkwụsị nke mgbochi nke ngwa agha dị ukwuu, na ike nke ndị ọrụ na-arụ ọrụ na-arụ ọrụ na-arụkwa ọrụ buru ibu, na ịrụ ọrụ nke ngwa agha adịghị mma.Methyl cellulose adhesion dị na agafeghị oke na ngwaahịa ether cellulose.

2. Hydroxypropylmethylcellulose (HPMC)

Hydroxypropyl methylcellulose bụ ụdị cellulose nke mmepụta na oriri ya na-abawanye ngwa ngwa n'afọ ndị na-adịbeghị anya.Ọ bụ ether na-abụghị ionic cellulose agwakọta nke sitere na owu a nụchara anụcha mgbe alkalization, na-eji propylene oxide na methyl chloride dị ka onye na-ahụ maka etherification, site na usoro mmeghachi omume.Ogo nke nnọchi bụ n'ozuzu 1.2 ~ 2.0.Ngwongwo ya dị iche iche n'ihi oke dị iche iche nke ọdịnaya methoxyl na ọdịnaya hydroxypropyl.

(1) Hydroxypropyl methylcellulose na-adị mfe mgbaze na mmiri oyi, ọ ga-enwekwa ihe isi ike na igbari na mmiri ọkụ.Ma gelation okpomọkụ ya na mmiri ọkụ dị nnọọ elu karịa nke methyl cellulose.A na-emeziwanye ihe solubility na mmiri oyi ma e jiri ya tụnyere methyl cellulose.

(2) Viscosity nke hydroxypropyl methylcellulose na-ejikọta ya na arọ molekụla ya, na ibu ibu nke molekụla, otú ahụ ka viscosity dị elu.Okpomọkụ na-emetụtakwa viscosity ya, ka okpomọkụ na-abawanye, viscosity na-ebelata.Otú ọ dị, nnukwu viscosity ya nwere mmetụta okpomọkụ dị ala karịa methyl cellulose.Ngwọta ya kwụsiri ike mgbe echekwara ya na ụlọ okpomọkụ.

(3) Njide mmiri nke hydroxypropyl methylcellulose na-adabere na ego mgbakwunye ya, viscosity, wdg, na ọnụ ọgụgụ njide mmiri ya n'okpuru otu ihe mgbakwunye ahụ dị elu karịa nke methyl cellulose.

(4) Hydroxypropyl methylcellulose kwụsiri ike na acid na alkali, na ngwọta mmiri ya kwụsiri ike na pH = 2 ~ 12.Caustic soda na mmiri lime enweghị mmetụta dị nta na arụmọrụ ya, mana alkali nwere ike mee ka mgbasa ya dị ngwa ma mee ka viscosity ya dịkwuo elu.Hydroxypropyl methylcellulose kwụsiri ike na nnu nkịtị, ma mgbe ntinye nke ngwọta nnu dị elu, viscosity nke hydroxypropyl methylcellulose ngwọta na-ebuli elu.

(5) Hydroxypropyl methylcellulose nwere ike ịgwakọta ya na mmiri-soluble polymer ogige na-etolite a edo na elu viscosity ngwọta.Dị ka mmanya polyvinyl, starch ether, chịngọm akwukwo nri, wdg.

(6) Hydroxypropyl methylcellulose nwere nguzogide enzyme dị mma karịa methylcellulose, na ohere nke mmebi enzymatic nke ngwọta ya dị ala karịa nke methylcellulose.Nrapanye nke hydroxypropyl methylcellulose na mgbidi ngwa agha dị elu karịa nke methylcellulose.

3. Hydroxyethyl cellulose (HEC)

A na-eme ya site na owu a nụchara anụcha na alkali, wee meghachi omume na ethylene oxide dị ka onye na-eme ka etherification na ọnụnọ acetone.Ogo nke nnọchi bụ n'ozuzu 1.5 ~ 2.0.Ọ nwere hydrophilicity siri ike ma dị mfe ịmịkọrọ mmiri.

(1) Hydroxyethyl cellulose na-agbaze na mmiri oyi, ma ọ na-esiri ike igbari na mmiri ọkụ.Ngwọta ya kwụsiri ike na oke okpomọkụ na-enweghị gelling.Enwere ike iji ya ogologo oge n'okpuru nnukwu okpomọkụ na ngwa agha, mana njide mmiri ya dị ala karịa nke methyl cellulose.

(2) Hydroxyethyl cellulose kwụsiri ike ruo n'ozuzu acid na alkali.Alkali nwere ike mee ka mgbasa ya dịkwuo ngwa ma mee ka viscosity ya dịkwuo ntakịrị.Mgbasa ya na mmiri dị ntakịrị njọ karịa nke methyl cellulose na hydroxypropyl methyl cellulose..

(3) Hydroxyethyl cellulose nwere ezigbo mgbochi sag arụmọrụ maka ngwa agha, ma ọ nwere ogologo oge na-azụ azụ maka ciment.

(4) Arụmọrụ nke hydroxyethyl cellulose nke ụfọdụ ụlọ ọrụ ụlọ na-emepụta dị ntakịrị ala karịa nke methyl cellulose n'ihi nnukwu mmiri na ọdịnaya ntụ dị elu.

4. Carboxymethyl cellulose (CMC)

Ionic cellulose ether bụ nke sitere n'okike emep uta eri (owu, wdg) mgbe a na-emeso ya na alkali na-eji dị ka etherification ihe site na usoro nke mmeghachi omume ọgwụgwọ.Ogo nke nnọchi n'ozuzu bụ 0.4 ~ 1.4, na ogo nke nnọchi na-emetụta arụmọrụ ya nke ukwuu.

(1) Carboxymethyl cellulose bụ ihe hygroscopic karịa, ọ ga-enwekwa mmiri karịa mgbe echekwara ya n'okpuru ọnọdụ izugbe.

(2) Carboxymethyl cellulose aqueous ngwọta adịghị emepụta gel, na viscosity na-ebelata na mmụba nke okpomọkụ.Mgbe okpomọkụ gafere 50 Celsius, viscosity agaghị agbanwe agbanwe.

(3) Nkwụsi ike ya na-emetụta pH nke ukwuu.N'ozuzu, enwere ike iji ya na ngwa ngwa gypsum, ma ọ bụghị n'igwe simenti.Mgbe nnukwu alkaline, ọ na-efunahụ viscosity.

(4) Njide mmiri ya dị nnọọ ala karịa nke methyl cellulose.Ọ na-enwe mmetụta azụ azụ na ngwa agha nke gypsum ma na-ebelata ike ya.Otú ọ dị, ọnụ ahịa carboxymethyl cellulose dị nnọọ ala karịa nke methyl cellulose

Ọrụ nke hydroxypropyl methylcellulose na ụlọ ọrụ mkpuchi: N'ihi na HPMC nwere ihe ndị yiri ya na ethers ndị ọzọ na-edozi mmiri, enwere ike iji ya dị ka onye na-emepụta ihe nkiri, thickener, emulsifier na stabilizer na emulsion paints na mmiri-soluble resin agba components.onye nnọchi anya, wdg, nke mere na mkpuchi ahụ nwere ezigbo mgbochi iyi.Ịkwado na nrapado, na mma elu esemokwu, nkwụsi ike na acid na alkali, na ndakọrịta na ọla pigmenti.N'ihi na ebe gel nke HPMC dị elu karịa nke MC, iguzogide nje bacteria na-esikwa ike karịa ethers cellulose ndị ọzọ, n'ihi ya, a pụrụ iji ya mee ihe dị ka ihe mkpuchi mmiri-emulsion.HPMC nwere ezi viscosity nchekwa kwụsie ike, na ọ nwere magburu onwe dispersibility, ya mere ọ bụ karịsịa adabara dị ka a dispersant na emulsified coatings.


Oge nzipu: Mar-04-2023
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