Kugwiritsa ntchito mfundo ndi kukonza mfundo ya cellulose ether
Chithunzi 1 chikuwonetsa kapangidwe ka cellose etrase. Chipinda chilichonse cha BD-anihdrogluc rocse (chobwereza chobwereza cha cellulose) chimasintha gulu limodzi ku C (2), c (3) ndi magulu atatu a ether. Chifukwa cha unyolo wa intra-trainingcellulose macromolecles, ndikovuta kusungunuka m'madzi ndipo pafupifupi onse oyipitsidwa. Kukhazikitsidwa kwa ma ethermine kudzera pakukula kwa ethermalecular ndi intermolecular hydrogen, kumathandizanso hydrophilicity yake, ndipo zimathandiza kwambiri kusandulika kwake pamadzi.
Magulu azomwe amapanga ndi magulu ocheperako a alkoxy ma alkoxy (1 mpaka 4 mitala) kapena ma hydroxyalkyl, omwe angalowe m'malo mwa magulu ena ogwirira ntchito monga Carboxyl kapena Amino. Mitundu itha kukhala ya mtundu umodzi kapena zingapo kapena zingapo. Pamodzi pa celroulecular unyolo, magulu a hydroxyl pa c (2), c (3) ndi c (6) maudindo onse a glucose ali m'malo osiyanasiyana. Kulankhula mosamalitsa, ma cellulose ether sikukhala ndi kapangidwe kake, kupatula zinthu zomwe zimasinthidwa kwathunthu ndi mtundu umodzi wa gulu (magulu onse atatu a hydroxyl ali m'malo). Zinthu izi zitha kugwiritsidwa ntchito posanthula labotale ndi kafukufuku, ndipo alibe phindu lamalonda.
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(b) chidutswa cha makeke a carboxymethylhydroxyethyl cellulose, digiri ya polowa m'malo a carboxymethyl ndi 0,5, digiri ya mitsempha ya hydroxethyl ndi 2.0, ndipo kuchuluka kwa kusintha kwa molar ndi 3.0. Kapangidwe kameneka kamaimira gawo lalikulu la magulu ozizira, koma miniti yolumikizira ndi yopanda tanthauzo.
Kwa gawo lililonse, kuchuluka kwathunthu kumafotokozedwa ndi digiri yazabwino. Mitundu ya DS ndi 0 ~ 3, yomwe ili yofanana ndi magulu wamba a hydroxyl yomwe idasinthidwa ndi magulu achinsinsi pagawo lililonse la alhydroglucose.
Kwa hydroxyalyl cellulose yokhazikika, yomwe imalowa m'malo mwa mitundu yatsopano ya hydroxyl, ndipo kuchuluka kwa zolowetsa zitha kungokhala ndi mtengo wa MS, ndiye kuti, kuchuluka kwa molar. Imayimira kuchuluka kwa maenje okwanira owonjezeredwa ku gulu lililonse la ternydroglucose. Chimodzi mwazonse ndi ethylene oxide ndipo malonda ali ndi hydroxyethyl m'malo. Pa Chithunzi 1, mtengo wa MS wazogulitsa ndi 3.0.
Mwambiri, palibe malire apamwamba a mtengo wa MS. Ngati phindu la kuchuluka kwa gawo lililonse la mphete iliyonse ya glucose imadziwika, kutalika kwakukulu kwa ether elemer opanga misa (WT%) kuyimira gawo lolowa m'malo mwa DS ndi mfundo za MS ndi MS. Gawo lalikulu la gulu lirilonse ndi mtengo wake kapena mtengo wa MS itha kusinthidwa ndi kuwerengera kosavuta.
Ma cellulose ambiri a cell ndi osungunuka osungunuka madzi, ndipo ena amasungunuka pang'ono mu ordic sol. Cellulose ether ali ndi mawonekedwe a chokwanira, mtengo wotsika, wosangalatsa, kudzipha kochepa komanso mitundu yosiyanasiyana, komanso magawo ogwiritsira ntchito ndi ntchito zofunsira zikukula. Monga wothandizira wothandizira, cellulose ether ili ndi ntchito zambiri zomwe zingachitike m'malo osiyanasiyana a mafakitale. ikhoza kupezeka ndi MS / DS.
Cellulose etter imakhazikitsidwa molingana ndi kapangidwe ka mankhwala ophatikizika mu Anionic, CARTIC komanso osagwirizana ndi ars. Zosagwirizana ndi zosungunuka zimatha kukhala zosungunuka ndi soluble.
Zinthu zomwe zakhala zikuyenda bwino zimalembedwa kumtunda kwa tebulo 1. Gawo lotsika la tebulo 1 limatchula magulu ena odziwika, omwe sanakhalepo ndi malonda ofunikira.
Dongosolo Lachidule la Oyimira Ethermitor Ortitunts Itha kutchulidwa malinga ndi zilembo za a zilembo kapena mgulu la DS (ms), mwachitsanzo, kwa 2-hydroxyelyl meth methylcellulose, ndipo zitha kulembedwanso kuti onetsetsani za methyl.
Magulu a hydroxyl pa cellulose samapezeka mosavuta ndi kusintha kwa mavesi, ndipo njira yopezera nthawi zambiri imachitika pansi pa mikhalidwe ya alkalinine, nthawi zambiri pogwiritsa ntchito ndende ina ya Naoh Alush. Cellulose yoyamba idapangidwa mu clykalel alkali cellulose ndi a Naoh aquirimication Njira Yothandizira Yothandizira. Pakupanga ndi kukonzekera zosakanizika eders, mitundu yosiyanasiyana ya othandizira iyenera kugwiritsidwa ntchito nthawi yomweyo, kapena kusintha kwa zitsamba iyenera kuchitika ndi kudyetsa kwina (ngati kuli kotheka). Pali mitundu inayi yomwe ikuchitika pakusinthika kwa cellulose, yomwe imafotokozedwa mwachidule ndi fomula (cellulosic imasinthidwa ndi cell-o) motere:
Equation (1) ikufotokozera momwe Williamson amatengera. RX ndi inorganic acid ester, ndipo x ndi halogen br, cl kapena sulfuric acid elster. Chloride R-cl nthawi zambiri amagwiritsidwa ntchito m'mafakitale, mwachitsanzo, methyl chloride, ethyl chloride kapena chlorooceic asidi. Kuchuluka kwa maziko a stoichiometric kumatha. Malonda otukuka a celluuse a ethyl celyl cellulose, ethyl cellulose ndi carboxymethyl cellulose ndi zinthu za Williamson Kudziwa.
Njira yothandizira (2) ndikuchita zomwe zimagwiritsidwa ntchito pa base-zothandizira epoxided (monga R = h, c2h5) ndi ma hydroxyl mamolekyu osakhala ndi ma molekyulu osamalira. Izi zikuchitika kuti magulu ambiri a hydroxyl amapangidwa panthawi yomwe aigollyyylene a Oligolylene axidi: . Zinthu monga hydroxethyl cellulose, hydroxypropyl cellulose ndi hydroxybutyl cellulose ndi zinthu zonse zopangidwa ndi epoxidation.
Njira yothandizira (3) Kodi zomwe zimachitika pakati pa maselo oh ndi organic zomwe zimakhala ndi zomangira ziwiri za alkaline, y ndi gulu la electron-loyatsidwa, Conh2, ndi NA. Masiku ano mtundu uwu sunagwiritsidwe ntchito.
Njira yazotsatira (4), zoyeserera ndi diazolkal sanali atakhala ndi mafakitale.
- Mitundu ya cellulose et
Cellulose ether imatha kukhala monoether kapena ether yosakaniza, ndipo mawonekedwe ake ndi osiyana. Pali mitundu yotsika kwambiri yopepuka pa celluese macromale Patsani malondawo kusandulika kwamadzi, ndipo mankhwala otsika-otsika amangokhala m'madzi kapena amatha kusungunuka pakuchepetsa yankho la alkalili. Ndi kafukufuku wakuya pazinthu za cellulose et, cellulose yatsopano enter ndi magawo awo ofunsira azipangidwa mosalekeza ndikupangidwa, ndipo mphamvu yayikulu kwambiri yogwiritsa ntchito yogwiritsa ntchito.
Lamulo lalikulu la mphamvu yamagulu osakanikirana pa solubility katundu ndi awa:
1) Kuchulukitsa zomwe zili m'magulu a hydrophobic mu malonda kuti muwonjezere Hydrobicity ya ether ndikutsitsa mfundo ya gel;
2) Kuchulukitsa zomwe zili m'magulu a hydrophilic (monga magulu a hydrothyl) kuti awonjezere mfundo yake;
3) The hydroxypropyl group is special, and proper hydroxypropylation can lower the gel temperature of the product, and the gel temperature of the medium hydroxypropylated product will rise again, but a high level of substitution will reduce its gel point ; Cholinga chake ndi chifukwa cha kuchuluka kwa kaboni kaboni kaboni ka katemera, hydroxypropropropropropropyl, ma hydrogen otsika mkati mwa macronule mu celroulecle, ndi hydrophilic hydroxyl ma unyolo. Madzi ndi olamulira. Komabe, ngati cholowa ndi chokwera, padzakhala polymerization m'mbali mwa gulu la ma hydroxyl chidzachepa, ndipo solubidicitity idzachepetsedwa m'malo mwake.
Kupanga ndi kafukufuku wacellulose etherali ndi mbiri yayitali. Mu 1905, Suida yoyamba idanena koyamba za kusinthika kwa cellulose, yomwe inali methyl ndi dimethyl sulfate. Alkyl alkyl alkyl anali ndi Lilnfeld (1912), Dreyfus (1914) ndi leuchs (1920) ya ma cellose osungunuka, motero. Buchler ndi Gomberg adatulutsa benzyl cellulose mu 1921, Carboxymethyl cellulose idapangidwa ndi Jansen mu 1918, ndipo Hubert adatulutsa Hydrothyll Cellusese. Kuyambira mu 1937 mpaka 1938, kupanga mafakitale kwa MC ndi Hec kunakwaniritsidwa ku United States. Sweden adayamba kupanga kupanga kwa echeble madzi mu 1945. Pambuyo pa 1945, kupanga cellulose ether ether ether ether ether etherth Etherth ku Western Europe, United States ndi Japan. Kumapeto kwa 1957, China CMC idayamba koyamba kupanga ku Shanghai Cellulioid fakitale. Podzafika pa 2004, dziko langa lopanga likhala litakhala matani 30,000 a ionic ether ether ndi matani 10,000 a ether. Pofika chaka cha 2007, ifika matani 100,000 a ionic ether ether ether etheel ether. Makampani olumikizana aukadaulo kunyumba ndi kunja amakangana kwina nthawi zonse, ndipo ma epel a eleluse opanga ma exality a Exather ndi ma cellulose amasintha nthawi zonse.
M'zaka zaposachedwa, ma cellulose opanga ma cellulose ndi mitundu yambiri yosakanizidwa ndi mfundo zosiyanasiyana dS, ma viscosties, oyera komanso zikhalidwe zamitundu. Pakadali pano, cholinga chachikulu cha chitukuko cham'munda wa cellulose ether akupanga ukadaulo wopangidwa, kukonzekera zatsopano, zida zatsopano, zinthu zapamwamba, komanso zinthu zodziwika bwino ziyenera kusanthulika mwamwambo.
Post Nthawi: Apr-282024