Yadda za a yi Cellulose ether?

Cellulose ether wani nau'i ne na cellulose wanda aka samu ta hanyar gyaran etherification na cellulose. Ana amfani dashi ko'ina saboda kyakkyawan kauri, emulsification, dakatarwa, samuwar fim, colloid mai kariya, riƙe danshi, da kaddarorin mannewa. Yana taka muhimmiyar rawa wajen bunkasa tattalin arzikin kasa a fannin binciken kimiyya da masana'antu kamar abinci, magunguna, yin takarda, sutura, kayan gini, dawo da mai, masaku da kayan lantarki. A cikin wannan takarda, an sake nazarin ci gaban bincike na etherification gyare-gyare na cellulose.

Celluloseethershi ne mafi yawan kwayoyin halitta polymer a yanayi. Yana da sabuntawa, kore kuma mai jituwa. Abu ne mai mahimmanci na asali don aikin injiniyan sinadarai. Dangane da madogara daban-daban akan kwayoyin da aka samu daga tasirin etherification, ana iya raba shi zuwa ethers guda ɗaya kuma gauraye. cellulose ethers.Anan mu yayi nazarin ci gaban bincike akan haɗin ethers guda ɗaya, ciki har da ethers alkyl, hydroxyalkyl ethers, carboxyalkyl ethers, da kuma gauraye ethers.

Mabuɗin kalmomi: cellulose ether, etherification, ether guda ɗaya, gauraye ether, ci gaban bincike

1.Etherification dauki na cellulose

Halin etherification na cellulose ether shine mafi mahimmancin halayen cellulose. Akwai nau'ikan samfuran ether cellulose da yawa, waɗanda za'a iya raba su zuwa ethers guda ɗaya da gauraye ethers bisa ga madogara daban-daban akan ƙwayoyin da aka samu daga halayen etherification. Za a iya raba ethers guda ɗaya zuwa alkyl ethers, hydroxyalkyl ethers da carboxyalkyl ethers, kuma gauraye ethers suna nufin ethers tare da ƙungiyoyi biyu ko fiye da aka haɗa a cikin tsarin kwayoyin halitta. Daga cikin samfuran ether cellulose, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC) ana wakilta, daga cikinsu an sayar da wasu samfuran.

2.Synthesis na cellulose ether

2.1 Haɗin ether guda ɗaya

Single ethers sun haɗa da ethers na alkyl (irin su ethyl cellulose, propyl cellulose, phenyl cellulose, cyanoethyl cellulose, da dai sauransu), hydroxyalkyl ethers (irin su hydroxymethyl cellulose, hydroxyethyl cellulose, da dai sauransu), carboxyalkyl ethers (irin su carboxymethyl cellulose, carboxymethyl cellulose). da sauransu).

2.1.1 Tsarin alkyl ethers

Berglund et al na farko da aka yi maganin cellulose tare da maganin NaOH da aka ƙara tare da ethyl chloride, sannan aka ƙara methyl chloride a zazzabi na 65°C zuwa 90°C da matsa lamba na 3bar zuwa 15bar, kuma ya amsa don samar da ether cellulose methyl. Wannan hanya na iya zama mai inganci Don samun ruwa mai narkewa methyl cellulose ethers tare da digiri daban-daban na maye gurbin.

Ethylcellulose wani farin thermoplastic granule ko foda. Gabaɗaya kayayyaki sun ƙunshi 44% ~ 49% ethoxy. Mai narkewa a cikin mafi yawan kaushi na halitta, wanda ba ya narkewa a cikin ruwa. da ɓangaren litattafan almara ko auduga linters tare da 40% ~ 50% sodium hydroxide ruwa bayani, da kuma alkalized cellulose aka ethoxylated da ethyl chloride don samar da ethyl cellulose. samu nasarar haɗa ethyl cellulose (EC) tare da abun ciki na ethoxy na 43.98% ta hanyar mataki ɗaya ta hanyar amsa cellulose tare da wuce haddi ethyl chloride da sodium hydroxide, ta amfani da toluene a matsayin diluent. An yi amfani da Toluene azaman diluent a cikin gwaji. A lokacin da etherification dauki, shi ba zai iya kawai inganta yaduwar ethyl chloride zuwa alkali cellulose, amma kuma narkar da sosai musanya ethyl cellulose. A lokacin amsawa, za a iya ci gaba da fallasa ɓangaren da ba a yi ba, yana yin wakili na etherification Yana da sauƙi don mamayewa, don haka tasirin ethylation ya canza daga nau'i-nau'i zuwa nau'i, kuma rarraba abubuwan maye a cikin samfurin ya fi dacewa.

An yi amfani da ethyl bromide azaman wakili na etherification da tetrahydrofuran azaman diluent don haɓaka ethyl cellulose (EC), kuma yana nuna tsarin samfurin ta hanyar infrared spectroscopy, resonance magnetic resonance da gel permeation chromatography. An ƙididdige cewa matakin maye gurbin ethyl cellulose da aka haɗa shine game da 2.5, yawan adadin kwayoyin halitta yana da kunkuntar, kuma yana da mai kyau solubility a cikin kwayoyin kaushi.

cyanoethyl cellulose (CEC) ta hanyar kamanni da hanyoyin daban-daban ta hanyar amfani da cellulose tare da digiri daban-daban na polymerization azaman albarkatun ƙasa, da kuma shirya kayan membrane masu yawa ta hanyar simintin simintin gyare-gyare da matsi mai zafi. An shirya membranes na CEC mai ƙarfi ta hanyar fasahar rabuwar lokaci mai ƙarfi (NIPS), da barium titanate/cyanoethyl cellulose (BT/CEC) nanocomposite membrane kayan fasahar NIPS aka shirya, kuma an yi nazarin tsarinsu da kaddarorinsu.

amfani da kai-raya cellulose sauran ƙarfi (alkali / urea bayani) a matsayin dauki matsakaici zuwa homogeneously synthesize cyanoethyl cellulose (CEC) tare da acrylonitrile a matsayin etherification wakili, da kuma gudanar da bincike a kan tsari, kaddarorin da aikace-aikace na samfurin. nazari mai zurfi. Kuma ta sarrafa yanayi daban-daban na amsawa, ana iya samun jerin CECs tare da ƙimar DS daga 0.26 zuwa 1.81.

2.1.2 Haɗin gwiwar ethers na hydroxyalkyl

Fan Junlin et al da aka shirya hydroxyethyl cellulose (HEC) a cikin 500 L reactor ta amfani da auduga mai ladabi azaman kayan albarkatun kasa da 87.7% isopropanol-ruwa azaman ƙarfi ta hanyar alkalization mataki-mataki, tsaka-tsakin mataki-mataki da etherification na mataki-mataki. . Sakamakon ya nuna cewa shirye-shiryen hydroxyethyl cellulose (HEC) yana da canjin molar MS na 2.2-2.9, wanda ya kai daidaitaccen ma'auni mai inganci kamar samfurin Dows 250 HEC na kasuwanci tare da maye gurbin molar na 2.2-2.4. Yin amfani da HEC a cikin samar da fenti na latex zai iya inganta kayan aikin fim da daidaita kayan fenti na latex.

Liu Dan da sauransu sun tattauna shirye-shiryen quaternary ammonium gishiri cationic hydroxyethyl cellulose ta hanyar Semi-bushe hanyar hydroxyethyl cellulose (HEC) da 2,3-epoxypropyltrimethylammonium chloride (GTA) a ƙarƙashin aikin alkali catalysis. yanayin ether. An bincika tasirin ƙara cationic hydroxyethyl cellulose ether akan takarda. Sakamakon gwaji ya nuna cewa: a cikin ɓangaren litattafan almara mai bleached, lokacin da maye gurbin digiri na cationic hydroxyethyl cellulose ether shine 0.26, jimlar riƙewa ya karu da 9%, kuma yawan tace ruwa yana ƙaruwa da 14%; a cikin ɓangaren litattafan almara na bleached, lokacin da adadin cationic hydroxyethyl cellulose ether shine 0.08% na fiber na ɓangaren litattafan almara, yana da tasiri mai mahimmanci akan takarda; mafi girman matsayi na maye gurbin cationic cellulose ether, mafi girman nauyin cajin cationic, kuma mafi kyawun tasirin ƙarfafawa.

Zhanhong yana amfani da hanyar haɗin ruwa-lokaci don shirya hydroxyethyl cellulose tare da ƙimar danko 5×104mpa·s ko fiye da ƙimar toka ƙasa da 0.3% ta hanyar matakai biyu na alkalization da etherification. An yi amfani da hanyoyin alkalization guda biyu. Hanya ta farko ita ce amfani da acetone a matsayin diluent. Danyen kayan cellulose ya samo asali ne kai tsaye a cikin wani takamaiman taro na maganin ruwa na sodium hydroxide. Bayan da basification dauki da za'ayi, an ƙara wani etherification wakili kai tsaye gudanar da etherification dauki. Hanya ta biyu ita ce, ana sanya danyen cellulose a cikin wani ruwa mai ruwa na sodium hydroxide da urea, sannan sai a matse alkali cellulose da aka shirya ta wannan hanya domin cire ledan da ya wuce gona da iri kafin a samu waraka. Sakamakon gwaji ya nuna cewa abubuwa kamar adadin diluent da aka zaɓa, adadin ethylene oxide da aka kara, lokacin alkalization, zafin jiki da lokacin amsawar farko, da zafin jiki da lokacin amsawa na biyu duk suna da tasiri mai yawa akan aikin. na samfurin.

Xu Qin et al. za'ayi etherification dauki na alkali cellulose da propylene oxide, da kuma hada hydroxypropyl cellulose (HPC) tare da low maye digiri ta gas-m lokaci hanya. An yi nazarin tasirin juzu'in juzu'i na propylene oxide, rabon matsi da zafin jiki na etherification akan matakin etherification na HPC da ingantaccen amfani da propylene oxide. Sakamakon ya nuna cewa mafi kyawun yanayin haɓakawa na HPC shine 20% propylene oxide mass juzu'i 20% (ma'auni rabo zuwa cellulose), alkali cellulose extrusion rabo 3.0, da etherification zafin jiki 60.°C. Gwajin tsari na HPC ta hanyar karfin maganadisu na nukiliya ya nuna cewa matakin etherification na HPC shine 0.23, ƙimar amfani mai inganci na propylene oxide shine 41.51%, kuma an sami nasarar haɗa sarkar kwayoyin cellulose tare da ƙungiyoyin hydroxypropyl.

Kong Xingjie et al. shirya hydroxypropyl cellulose tare da ionic ruwa a matsayin sauran ƙarfi gane kama dauki na cellulose don gane da tsari na dauki tsari da kuma kayayyakin. A lokacin gwajin, an yi amfani da imidazole phosphate ionic ruwa 1, 3-diethylimidazole diethyl phosphate don narke microcrystalline cellulose, kuma an samo hydroxypropyl cellulose ta hanyar alkalization, etherification, acidification, da wankewa.

2.1.3 Haɗin ethers na carboxyalkyl

Mafi na kowa carboxymethyl cellulose ne carboxymethyl cellulose (CMC). Maganin ruwa mai ruwa na carboxymethyl cellulose yana da ayyuka na thickening, film forming, bonding, ruwa riƙewa, colloid kariya, emulsification da dakatarwa, kuma ana amfani da ko'ina a wanke. Pharmaceuticals, abinci, man goge baki, yadi, bugu da rini, yin takarda, man fetur, hakar ma’adinai, magani, yumbu, kayan lantarki, roba, fenti, magungunan kashe qwari, kayan kwalliya, fata, robobi da hako mai, da sauransu.

A cikin 1918, Jamus E. Jansen ya ƙirƙira hanyar haɗakarwa ta carboxymethyl cellulose. A cikin 1940, masana'antar Kalle na Kamfanin IG Farbeninaustrie na Jamus sun sami nasarar samar da masana'antu. A cikin 1947, Kamfanin Wyandotle Chemical na Amurka ya sami nasarar haɓaka tsarin samar da ci gaba. Ƙasata ta fara fara samar da masana'antu na CMC a masana'antar Celluloid ta Shanghai a cikin 1958. Carboxymethyl cellulose shine ether cellulose da aka samar daga auduga mai ladabi a ƙarƙashin aikin sodium hydroxide da chloroacetic acid. Hanyoyin samar da masana'anta za a iya raba su zuwa nau'i biyu: hanyar tushen ruwa da hanyar tushen ƙarfi bisa ga kafofin watsa labaru daban-daban. Hanyar da ake amfani da ruwa a matsayin hanyar amsawa ana kiranta hanyar ruwa mai matsakaici, kuma tsarin da ke dauke da kwayoyin halitta a cikin hanyar amsawa shine ake kira hanyar warwarewa.

Tare da zurfafa bincike da ci gaban fasaha, an yi amfani da sababbin yanayi na amsawa ga kira na carbonoxymethyl cellulose, kuma sabon tsarin narkewa yana da tasiri mai mahimmanci akan tsarin amsawa ko ingancin samfurin. Olaru et al. gano cewa carboxymethylation dauki na cellulose ta amfani da ethanol-acetone gauraye tsarin ya fi na ethanol ko acetone kadai. Nicholson et al. A cikin tsarin, an shirya CMC tare da ƙananan digiri na maye gurbin. Philipp et al sun shirya sosai CMC da aka maye gurbinsu da N-methylmorpholine-N oxide da N, N dimethylacetamide/lithium chloride ƙarfi tsarin bi da bi. Kai et al. ɓullo da wata hanya don shirya CMC a NaOH/urea ƙarfi tsarin. Ramos et al. yayi amfani da tsarin ruwa na DMSO/tetrabutylammonium fluoride ionic ruwa a matsayin mai narkewa don carboxymethylate da albarkatun cellulose mai ladabi daga auduga da sisal, kuma ya sami samfurin CMC tare da digiri na maye gurbin har zuwa 2.17. Chen Jinghuan et al. amfani da cellulose tare da babban ɓangaren litattafan almara (20%) a matsayin albarkatun kasa, sodium hydroxide da acrylamide a matsayin gyare-gyare reagents, za'ayi carboxyethylation gyara dauki a saita lokaci da zazzabi, kuma a karshe samu carboxyethyl tushe cellulose. Ana iya daidaita abun ciki na carboxyethyl na samfurin da aka gyara ta canza adadin sodium hydroxide da acrylamide.

2.2 Haɗin haɗin ethers

Hydroxypropyl methyl cellulose ether wani nau'i ne na cellulose ether mara iyaka a cikin ruwan sanyi wanda aka samo daga cellulose na halitta ta hanyar alkalization da gyaran etherification. An sanya shi tare da maganin sodium hydroxide kuma an ƙara wani adadin adadin isopropanol da sauran ƙarfi na toluene, wakilin etherification wanda ke ɗauka shine methyl chloride da propylene oxide.

Dai Mingyun et al. amfani da hydroxyethyl cellulose (HEC) a matsayin kashin baya na hydrophilic polymer, da kuma grafted da hydrophobizing wakili butyl glycidyl ether (BGE) a kan kashin baya ta etherification dauki don daidaita hydrophobic kungiyar butyl. Matsayin maye gurbin ƙungiyar, don haka yana da ƙimar ma'auni mai dacewa na hydrophilic-lipophilic, kuma an shirya 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC) mai zafin jiki; an shirya dukiya mai ɗaukar zafin jiki Kayan aiki na tushen cellulose yana ba da sabuwar hanya don aikace-aikacen kayan aiki a cikin fagagen ci gaba da saki da ilmin halitta.

Chen Yangming da sauransu sun yi amfani da hydroxyethyl cellulose a matsayin ɗanyen abu, kuma a cikin tsarin maganin isopropanol, sun ƙara ƙaramin adadin Na2B4O7 zuwa mai amsawa don amsawar kamanni don shirya gauraye ether hydroxyethyl carboxymethyl cellulose. Samfurin yana nan take a cikin ruwa, kuma Danko yana da ƙarfi.

Wang Peng yana amfani da na halitta cellulose mai ladabi auduga a matsayin asali albarkatun kasa, kuma yana amfani da wani mataki etherification tsari don samar da carboxymethyl hydroxypropyl cellulose tare da uniform dauki, high danko, mai kyau acid juriya da gishiri juriya ta hanyar alkalization da etherification halayen hada ether. Yin amfani da tsarin etherification na mataki ɗaya, samar da carboxymethyl hydroxypropyl cellulose yana da kyakkyawan juriya na gishiri, juriya na acid da solubility. Ta hanyar canza adadin dangin propylene oxide da chloroacetic acid, ana iya shirya samfuran tare da abubuwan da ke cikin carboxymethyl da hydroxypropyl daban-daban. Sakamakon gwajin ya nuna cewa carboxymethyl hydroxypropyl cellulose da aka samar ta hanyar mataki ɗaya yana da ɗan gajeren sake zagayowar samarwa, ƙarancin ƙarfi, kuma samfurin yana da kyakkyawan juriya ga salts monovalent da divalent da kuma juriya mai kyau na acid. Idan aka kwatanta da sauran samfuran ether cellulose, yana da ƙarfi mai ƙarfi a fagen abinci da binciken mai.

Hydroxypropylmethylcellulose (HPMC) shine nau'in da ya fi dacewa kuma mafi kyawun aiki a tsakanin kowane nau'in cellulose, kuma shi ma wakilci ne na tallace-tallace a tsakanin gauraye ethers. A cikin 1927, an sami nasarar haɗa hydroxypropylmethylcellulose (HPMC) kuma an keɓe shi. A cikin 1938, Dow Chemical Co. na Amurka ya fahimci samar da masana'antu na methyl cellulose kuma ya haifar da sanannen alamar kasuwanci "Methocel". Babban sikelin masana'antu samar da hydroxypropyl methylcellulose fara a Amurka a 1948. Samar da tsarin na HPMC za a iya raba biyu Categories: gas lokaci hanya da kuma ruwa lokaci hanya. A halin yanzu, kasashen da suka ci gaba kamar Turai, Amurka da Japan sun fi daukar tsarin tafiyar da iskar gas, kuma samar da HPMC a cikin gida ya dogara ne akan tsarin tsarin ruwa.

Zhang Shuangjian da sauransu mai ladabi auduga foda a matsayin albarkatun kasa, alkalized shi da sodium hydroxide a dauki matsakaici toluene da isopropanol, etherified shi da etherifying wakili propylene oxide da methyl chloride, reacted da kuma shirya wani irin nan take hydroxypropyl methyl barasa tushe cellulose ether.

3. Outlook

Cellulose wani muhimmin sinadari ne da danyen sinadari wanda ke da wadatar albarkatu, kore da kare muhalli, kuma ana iya sabuntawa. Abubuwan da aka samo asali na gyare-gyaren etherification na cellulose suna da kyakkyawan aiki, yawan amfani da amfani da tasiri mai kyau, kuma suna biyan bukatun tattalin arzikin kasa zuwa babban matsayi. Kuma bukatun ci gaban zamantakewa, tare da ci gaba da ci gaban fasaha da kuma fahimtar kasuwanci a nan gaba, idan kayan aiki na roba da kuma hanyoyin da ake amfani da su na cellulose na iya zama masana'antu, za a yi amfani da su sosai kuma su gane aikace-aikace masu yawa. Daraja