Menene Cellulose Ether?

Cellulose etherwani fili ne na polymer tare da tsarin ether wanda aka yi da cellulose. Kowane zobe na glucosyl a cikin macromolecule cellulose ya ƙunshi ƙungiyoyin hydroxyl guda uku, rukunin farko na hydroxyl akan atom na shida na carbon, ƙungiyar hydroxyl ta biyu akan atom ɗin carbon na biyu da na uku, kuma hydrogen a cikin rukunin hydroxyl an maye gurbinsu da ƙungiyar hydrocarbon don samar da abubuwan abubuwan da suka samo asali na cellulose ether. Wani samfur ne wanda hydrogen na ƙungiyar hydroxyl a cikin polymer cellulose ya maye gurbinsa da ƙungiyar hydrocarbon. Cellulose wani fili ne na polyhydroxy polymer wanda baya narkewa kuma baya narkewa. Bayan etherification, cellulose ne mai narkewa a cikin ruwa, diluted alkali bayani da kwayoyin kaushi, kuma yana da thermoplasticity.

Cellulose wani fili ne na polyhydroxy polymer wanda baya narkewa kuma baya narkewa. Bayan etherification, cellulose ne mai narkewa a cikin ruwa, diluted alkali bayani da kwayoyin kaushi, kuma yana da thermoplasticity.

1. Nature:

Solubility na cellulose bayan etherification yana canzawa sosai. Ana iya narkar da shi a cikin ruwa, dilute acid, dilute alkali ko Organic sauran ƙarfi. Solubility yafi dogara ne akan abubuwa guda uku: (1) Halayen ƙungiyoyin da aka gabatar a cikin tsarin etherification, da aka gabatar da mafi girma ƙungiyar, ƙananan solubility, kuma mafi karfi da polarity na rukunin da aka gabatar, da sauƙi ether cellulose shine narke cikin ruwa; (2) Matsayin maye gurbin da rarraba ƙungiyoyin etherified a cikin macromolecule. Yawancin ethers cellulose kawai za a iya narkar da su a cikin ruwa a ƙarƙashin wani nau'i na maye gurbin, kuma matakin maye gurbin yana tsakanin 0 da 3; (3) Matsayin polymerization na ether cellulose, mafi girman digiri na polymerization, ƙananan mai narkewa; Ƙananan matakin maye gurbin da za a iya narkar da shi a cikin ruwa, mafi fadi da kewayon. Akwai nau'ikan ethers na cellulose da yawa tare da kyakkyawan aiki, kuma ana amfani dasu sosai a cikin gine-gine, siminti, man fetur, abinci, yadi, wanka, fenti, magani, yin takarda da kayan lantarki da sauran masana'antu.

2. Ci gaba:

Kasar Sin ita ce kasa mafi girma a duniya wajen samarwa da masu amfani da sinadarin cellulose ether, tare da matsakaicin karuwar karuwar sama da kashi 20 cikin dari a kowace shekara. Bisa kididdigar farko da aka yi, akwai masana'antun samar da ether kusan 50 a kasar Sin, aikin da aka tsara na samar da ether ya zarce tan 400,000, kuma akwai kamfanoni kusan 20 da ke da fiye da ton 10,000, wadanda aka rarraba a yankunan Shandong, Hebei, Chongqing da Jiangsu. , Zhejiang, Shanghai da sauran wurare.

3. Bukata:

A shekarar 2011, karfin samar da CMC na kasar Sin ya kai tan 300,000. Tare da karuwar buƙatar ethers cellulose masu inganci a masana'antu irin su magani, abinci, da sinadarai na yau da kullun, buƙatun gida na sauran samfuran ether cellulose banda CMC yana ƙaruwa. , da ikon samar da MC/HPMC ne game da 120,000 ton, da na HEC ne game da 20,000 ton. PAC har yanzu yana cikin haɓakawa da matakin aikace-aikace a China. Tare da bunƙasa manyan rijiyoyin mai a teku da haɓaka kayan gini, abinci, sinadarai da sauran masana'antu, adadin da filin PAC yana ƙaruwa kuma yana ƙaruwa kowace shekara, tare da ikon samar da fiye da ton 10,000.

4. Rarraba:

Dangane da tsarin sinadarai na rarrabuwa na masu maye, ana iya raba su zuwa anionic, cationic da nonionic ethers. Dangane da etherification wakili da aka yi amfani da, akwai methyl cellulose, hydroxyethyl methyl cellulose, carboxymethyl cellulose, ethyl cellulose, benzyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose cellulose, cyanoethyl cellulose, benzyl cyanoethyl cellulose, carboxymethyl cellulose. cellulose da ethyl cellulose sun fi amfani.

Methylcellulose:

Bayan an yi amfani da auduga mai ladabi tare da alkali, ana samar da ether cellulose ta hanyar jerin halayen da methane chloride a matsayin wakili na etherification. Gabaɗaya, matakin maye gurbin shine 1.6 ~ 2.0, kuma solubility shima ya bambanta da digiri daban-daban na maye gurbin. Nasa ne ga wadanda ba ionic cellulose ether.

(1) Methylcellulose yana narkewa a cikin ruwan sanyi, kuma zai yi wuya a narke cikin ruwan zafi. Maganin ruwan sa yana da ƙarfi sosai a cikin kewayon pH = 3 ~ 12. Yana da kyau dacewa tare da sitaci, guar danko, da dai sauransu da yawa surfactants. Lokacin da zafin jiki ya kai ga zafin jiki na gelation, gelation yana faruwa.

(2) Riƙewar ruwa na methyl cellulose ya dogara da adadin adadinsa, danko, girman barbashi da adadin rushewa. Gabaɗaya, idan adadin ƙari yana da girma, ƙarancin ƙarancin ƙanƙara ne, kuma danko yana da girma, yawan riƙe ruwa yana da girma. Daga cikin su, adadin ƙarawa yana da tasiri mafi girma a kan yawan adadin ruwa, kuma matakin danko ba daidai ba ne kai tsaye zuwa matakin yawan ruwa. A rushe kudi yafi dogara a kan mataki na surface gyara na cellulose barbashi da barbashi fineness. Daga cikin ethers cellulose da ke sama, methyl cellulose da hydroxypropyl methyl cellulose suna da ƙimar riƙe ruwa mafi girma.

(3) Canje-canje a cikin zafin jiki na iya tasiri sosai ga riƙewar ruwa na methyl cellulose. Gabaɗaya, mafi girman zafin jiki, mafi munin riƙewar ruwa. Idan yawan zafin jiki na turmi ya wuce 40 ° C, riƙewar ruwa na methyl cellulose zai ragu sosai, yana tasiri sosai ga ginin turmi.

(4)Methyl celluloseyana da tasiri mai mahimmanci akan aiki da haɗin kai na turmi. “Mannewa” a nan yana nufin ƙarfin haɗin gwiwa da ake ji tsakanin kayan aikin ma’aikaci da katangar bango, wato, juriyar juriyar turmi. Manne yana da girma, juriya na juriya na turmi yana da girma, kuma ƙarfin da ma'aikata ke bukata a cikin aikin da ake amfani da su yana da girma, kuma aikin ginin turmi ba shi da kyau. Haɗin kai na methyl cellulose yana a matsakaicin matakin a cikin samfuran ether cellulose.

Hydroxypropylmethylcellulose:

Hydroxypropyl methylcellulose wani nau'in cellulose ne wanda fitarwa da amfaninsa ke karuwa cikin sauri. Yana da ether wanda ba na ionic cellulose ba wanda aka yi daga auduga mai ladabi bayan alkalization, ta amfani da propylene oxide da methyl chloride a matsayin wakili na etherification, ta hanyar jerin halayen. Matsakaicin maye gaba ɗaya shine 1.2 ~ 2.0. Kaddarorinsa sun bambanta dangane da rabon abun ciki na methoxyl zuwa abun ciki na hydroxypropyl.

(1) Hydroxypropyl methylcellulose yana da sauƙin narkewa a cikin ruwan sanyi, kuma zai gamu da matsaloli wajen narkewa cikin ruwan zafi. Amma zafinsa na gelation a cikin ruwan zafi yana da girma fiye da na methyl cellulose. Solubility a cikin ruwan sanyi kuma yana inganta sosai idan aka kwatanta da methyl cellulose.

(2) Dankin hydroxypropyl methylcellulose yana da alaƙa da nauyin kwayoyin halitta, kuma mafi girman nauyin kwayoyin halitta, mafi girman danko. Hakanan yanayin zafi yana rinjayar danko, yayin da zafin jiki ya karu, danko yana raguwa. Duk da haka, tasirin babban danko da zafinsa ya yi ƙasa da na methyl cellulose. Maganin sa yana da ƙarfi idan an adana shi a cikin zafin jiki.

(3) Riƙewar ruwa na hydroxypropyl methylcellulose ya dogara ne akan ƙarin adadinsa, danko, da dai sauransu, kuma yawan ajiyar ruwa a ƙarƙashin adadin adadin adadin ya fi na methyl cellulose.

(4)Hydroxypropyl methylcelluloseyana da kwanciyar hankali ga acid da alkali, kuma maganin sa na ruwa yana da ƙarfi sosai a cikin kewayon pH = 2 ~ 12. Caustic soda da ruwan lemun tsami suna da ɗan tasiri akan aikin sa, amma alkali na iya hanzarta rushewar kuma ya ɗan ƙara danko. Hydroxypropyl methylcellulose ya tsaya tsayin daka ga gishiri na kowa, amma lokacin da maida hankali na maganin gishiri ya yi girma, dankowar maganin hydroxypropyl methylcellulose yana kula da karuwa.

(5) Hydroxypropyl methylcellulose za a iya haxa shi da ruwa mai narkewa polymer mahadi don samar da uniform da mafi girma danko bayani. Kamar polyvinyl barasa, sitaci ether, kayan lambu danko, da dai sauransu.

(6).

(7) Mannewar hydroxypropyl methylcellulose zuwa ginin turmi ya fi na methylcellulose girma.

Hydroxyethyl cellulose:

An yi shi daga auduga mai ladabi da aka yi da alkali, kuma an yi shi da ethylene oxide a matsayin wakili na etherification a gaban isopropanol. Matsayinsa na maye gurbin shine gabaɗaya 1.5 ~ 2.0. Yana da karfi hydrophilicity kuma yana da sauƙin sha danshi.

(1) Hydroxyethyl cellulose yana narkewa a cikin ruwan sanyi, amma yana da wuya a narke cikin ruwan zafi. Maganin sa yana da ƙarfi a babban zafin jiki ba tare da gelling ba. Ana iya amfani da shi na dogon lokaci a ƙarƙashin yanayin zafi mai zafi a turmi, amma riƙewar ruwa ya fi na methyl cellulose.

(2) Hydroxyethyl cellulose ne barga zuwa general acid da alkali, kuma alkali iya hanzarta narkar da kuma dan kadan ƙara da danko. Rarrabuwar sa a cikin ruwa ya ɗan yi muni fiye da na methyl cellulose da hydroxypropyl methyl cellulose.

(3) Hydroxyethyl cellulose yana da kyakkyawan aikin anti-sag don turmi, amma yana da lokaci mai tsawo don ciminti.

(4) Ayyukan hydroxyethyl cellulose da wasu masana'antun cikin gida ke samarwa a fili ya yi ƙasa da na methyl cellulose saboda yawan ruwa da kuma yawan toka.

(5) Mildew na maganin ruwa na hydroxyethyl cellulose yana da muni. A zafin jiki na kimanin 40 ° C, mildew na iya faruwa a cikin kwanaki 3 zuwa 5, wanda zai shafi aikinsa.

Carboxymethyl cellulose:

Lonic cellulose ether an yi shi ne daga filaye na halitta (auduga, da dai sauransu) bayan maganin alkali, ta yin amfani da sodium monochloroacetate a matsayin wakili na etherification, da kuma jurewa jerin jiyya. Matsakaicin maye gaba ɗaya shine 0.4 ~ 1.4, kuma aikin sa yana tasiri sosai ta matakin maye gurbin.

(1) Carboxymethyl cellulose ya fi hygroscopic, kuma zai ƙunshi ƙarin ruwa lokacin da aka adana shi a ƙarƙashin yanayi na yau da kullum.

(2) Maganin ruwa na Carboxymethyl cellulose baya samar da gel, kuma danko yana raguwa tare da karuwar zafin jiki. Lokacin da zafin jiki ya wuce 50 ° C, danko ba zai iya jurewa ba.

(3) kwanciyar hankali yana tasiri sosai ta pH. Gabaɗaya, ana iya amfani da shi a cikin turmi na tushen gypsum, amma ba a cikin turmi na tushen siminti ba. Lokacin da alkaline sosai, zai rasa danko.

(4) Riƙewar ruwansa yayi ƙasa da methyl cellulose. Yana da tasiri mai tasiri akan turmi na tushen gypsum kuma yana rage ƙarfinsa. Duk da haka, farashin carboxymethyl cellulose yana da ƙasa sosai fiye da na methyl cellulose.

Cellulose Alkyl Ether:

Wakilan sune methyl cellulose da ethyl cellulose. A cikin samar da masana'antu, methyl chloride ko ethyl chloride ana amfani dashi gabaɗaya azaman wakili na etherification, kuma halayen shine kamar haka:

A cikin dabarar, R yana wakiltar CH3 ko C2H5. Tattalin Arziki ba wai kawai yana rinjayar matakin etherification ba, har ma yana rinjayar amfani da alkyl halides. Ƙarƙashin ƙwayar alkali, mafi ƙarfin hydrolysis na alkyl halide. Don rage yawan amfani da wakili na etherifying, dole ne a ƙara yawan ƙwayar alkali. Koyaya, lokacin da aka rage yawan alkyabbar alkali sosai, an rage tasirin kumburi na selulose, wanda ba zai iya amfani da hakkin eBhoration ba, kuma saboda haka ana rage yawan eheritation. Don wannan dalili, za'a iya ƙara ƙwanƙwasa lemun tsami ko ƙwanƙwasa a yayin da ake amsawa. Reactor yakamata ya kasance yana da na'urar motsa jiki mai kyau da tsagewa ta yadda za'a iya rarraba alkali daidai gwargwado. Methyl cellulose ne yadu amfani da thickener, m da m colloid da dai sauransu Har ila yau, za a iya amfani da a matsayin dispersant ga emulsion polymerization, a bonding dispersant ga tsaba, a yadi slurry, wani ƙari ga abinci da kayan shafawa, wani likita m, wani magani shafi abu, da kuma amfani da latex Paint, bugu Yi amfani da tawada, da kuma ƙara da gauraye da ciminti saitin, lokacin da aka yi amfani da sumunti, da kuma ƙara lokacin da aka samar da sumunti, da kuma samar da lokaci a cikin samar da ƙarfi. da dai sauransu Ethyl cellulose kayayyakin da high inji ƙarfi, sassauci, zafi juriya da sanyi juriya. Ƙananan ethyl cellulose mai maye gurbin yana narkewa a cikin ruwa kuma yana tsarma maganin alkaline, kuma samfuran da aka maye gurbinsu suna narkewa a mafi yawan kaushi na kwayoyin halitta. Yana da kyau dacewa tare da daban-daban resins da plasticizers. Ana iya amfani da shi don yin robobi, fina-finai, varnishes, adhesives, latex da kayan shafa don magunguna, da dai sauransu Gabatarwar ƙungiyoyin hydroxylkyl a cikin cellulose alkyl ethers na iya inganta solubility, rage yawan jiyya ga salting, ƙara yawan zafin jiki na gelation da inganta kaddarorin zafi mai zafi, da dai sauransu. Matsayin canji a cikin abubuwan da ke sama ya bambanta da yanayin da ake kira substituxyl hydroxylk.

Cellulose Hydroxyalkyl Ether:

Wakilan sune hydroxyethyl cellulose da hydroxypropyl cellulose. Etherifying jamiái su ne epoxides kamar ethylene oxide da propylene oxide. Yi amfani da acid ko tushe a matsayin mai kara kuzari. Samar da masana'antu shine don amsa alkali cellulose tare da wakili na etherification:hydroxyethyl cellulosetare da babban canji darajar yana narkewa a cikin ruwan sanyi da ruwan zafi. Hydroxypropyl cellulose tare da babban canji darajar yana narkewa ne kawai a cikin ruwan sanyi amma ba cikin ruwan zafi ba. Hydroxyethyl cellulose za a iya amfani da a matsayin thickener ga latex coatings, yadi bugu da rini pastes, takarda size kayan, adhesives da m colloid. Amfani da hydroxypropyl cellulose yayi kama da na hydroxyethyl cellulose. Hydroxypropyl cellulose tare da ƙananan ƙimar musanyawa za'a iya amfani dashi azaman kayan haɓakar magunguna, wanda zai iya samun duka abubuwan ɗaurewa da tarwatsawa.

Carboxymethyl cellulose, gajartawar Ingilishi CMC, gabaɗaya tana wanzuwa ta hanyar gishirin sodium. Wakilin etherifying shine monochloroacetic acid, kuma amsawar shine kamar haka:

Carboxymethyl cellulose shine mafi yawan amfani da ether mai narkewa da ruwa. A da, an yafi amfani da shi azaman hakowa laka, amma a yanzu an mika shi a matsayin ƙari na wanka, slurry tufafi, latex Paint, shafi na kwali da takarda, da dai sauransu. Pure carboxymethyl cellulose za a iya amfani da a abinci, magani, kayan shafawa, da kuma a matsayin m ga tukwane da molds.

Polyanionic cellulose (PAC) ne ionic cellulose ether kuma shi ne babban-karshen samfurin maye gurbin carboxymethyl cellulose (CMC). Yana da farin, kashe-fari ko dan kadan rawaya foda ko granule, ba mai guba, m, mai sauki narke cikin ruwa don samar da wani m bayani tare da wani danko, yana da mafi zafi juriya kwanciyar hankali da gishiri juriya, da kuma karfi antibacterial Properties. Babu mildew da lalacewa. Yana da halaye na babban tsarki, babban matsayi na maye gurbin, da rarraba iri ɗaya na maye gurbin. Ana iya amfani da shi azaman ɗaure, thickener, rheology modifier, ruwa asarar rage, dakatar da stabilizer, da dai sauransu Polyanionic cellulose (PAC) ne yadu amfani a duk masana'antu inda CMC za a iya amfani da, wanda zai iya ƙwarai rage sashi, sauƙaƙe amfani, samar da mafi kwanciyar hankali da kuma saduwa mafi girma tsari bukatun.

Cyanoethyl cellulose shine samfurin amsawa na cellulose da acrylonitrile a ƙarƙashin catalysis na alkali.

Cyanoethyl cellulose yana da babban dielectric akai-akai da ƙarancin asara kuma ana iya amfani dashi azaman matrix resin don phosphor da fitilu na lantarki. Za a iya amfani da ƙananan musanya cyanoethyl cellulose azaman insulating takarda don masu canji.

An shirya manyan ethers barasa mai kitse, alkenyl ethers, da ethers barasa mai ƙanshi na cellulose, amma ba a yi amfani da su a aikace ba.

Hanyoyin shirye-shiryen ether na cellulose za a iya raba su zuwa hanyar matsakaici na ruwa, hanyar narkewa, hanyar kneading, hanyar slurry, hanyar gas mai ƙarfi, hanyar lokaci na ruwa da haɗuwa da hanyoyin da ke sama.

5.Ka'idar shiri:

Babban α-cellulose ɓangaren litattafan almara yana jiƙa da maganin alkaline don kumbura shi don lalata ƙarin haɗin gwiwar hydrogen, sauƙaƙe watsawar reagents da samar da alkali cellulose, sa'an nan kuma amsa tare da etherification wakili don samun cellulose ether. Abubuwan da ke daɗaɗawa sun haɗa da hydrocarbon halides (ko sulfates), epoxides, da α da β mahaɗan da ba a yarda da su ba tare da masu karɓar lantarki.

6.Basic aiki:

Admixtures suna taka muhimmiyar rawa wajen inganta aikin ginin busassun busassun turmi, kuma suna da fiye da kashi 40% na farashin kayan a cikin busassun turmi. Wani babban sashi na admixture a cikin kasuwannin cikin gida ana ba da shi ta masana'antun ƙasashen waje, kuma ma'auni na samfurin kuma ana ba da shi ta hanyar mai kaya. Sakamakon haka, farashin kayan busassun busassun busassun turmi ya kasance mai yawa, kuma yana da wahala a yada jita-jita na gama-gari da plastering turmi tare da adadi mai yawa da kewayo. Kamfanoni na kasashen waje ne ke sarrafa kayayyakin kasuwa masu daraja, kuma masu sana’ar busassun turmi da aka cakude ba su da riba mai yawa da rashin araha; aikace-aikace na admixtures rasa na tsari da kuma niyya bincike, da kuma makanta bin hanyoyin kasashen waje.

Wakilin riƙe ruwa shine maɓalli mai mahimmanci don haɓaka aikin riƙewar ruwa na busassun turmi mai gauraya, kuma yana ɗaya daga cikin maɓalli masu mahimmanci don tantance farashin busassun kayan turmi. Babban aikin ether cellulose shine riƙewar ruwa.

Cellulose ether shine kalma na gaba ɗaya don jerin samfurori da aka samar ta hanyar amsawar alkali cellulose da etherifying wakili a ƙarƙashin wasu yanayi. Alkali cellulose an maye gurbinsu da daban-daban etherifying jamiái don samun daban-daban cellulose ethers. Dangane da kaddarorin ionization na masu maye, ana iya raba ethers cellulose zuwa kashi biyu: ionic (kamar carboxymethyl cellulose) da nonionic (kamar methyl cellulose). Dangane da nau'in maye gurbin, ana iya raba ether cellulose zuwa monoether (kamar methyl cellulose) da ether gauraye (kamar hydroxypropyl methyl cellulose). A cewar daban-daban solubility, shi za a iya raba zuwa ruwa solubility (kamar hydroxyethyl cellulose) da Organic sauran ƙarfi solubility (kamar ethyl cellulose). Turmi-busasshen da aka haɗe shine cellulose mai narkewa da ruwa, kuma cellulose mai narkewar ruwa ya kasu zuwa nau'in nan take da nau'in jinkiri-nau'i mai jinkiri.

Hanyar aikin ether cellulose a cikin turmi shine kamar haka:

(1)Bayancellulose ethera cikin turmi yana narkar da ruwa, ana tabbatar da ingantaccen rarraba kayan siminti a cikin tsarin saboda aikin saman, da ether cellulose, azaman colloid mai kariya, “nannade” daskararrun barbashi da Layer na fim ɗin lubricating an kafa shi akan farfajiyar ta ta waje, wanda ke sa tsarin turmi ya fi kwanciyar hankali, kuma yana inganta haɓakar ruwa da haɓakar turmi yayin aikin ginin.

(2) Saboda tsarinsa na kwayoyin halitta, maganin cellulose ether yana sa danshi a cikin turmi ba shi da sauƙi a rasa, kuma a hankali ya sake shi na dogon lokaci, yana ba da turmi mai kyau na ruwa da kuma aiki.