Cellulose etherification gyara

01. Gabatarwa na cellulose

Cellulose shine polysaccharide macromolecular wanda ya ƙunshi glucose. Rashin narkewa a cikin ruwa da sauran kaushi na kwayoyin halitta. Ita ce babban bangaren bangon tantanin halitta, kuma ita ce mafi yawan rarrabawa kuma mafi yawan polysaccharide a yanayi.

Cellulose ita ce mafi yawan albarkatu da za a iya sabuntawa a duniya, kuma ita ce polymer na halitta tare da tarin mafi girma. Yana da fa'idodi na kasancewa mai sabuntawa, gaba ɗaya mai yuwuwa, da ingantaccen yanayin halitta.

02. Dalilan gyara cellulose

Cellulose macromolecules sun ƙunshi babban adadin ƙungiyoyin -OH. Saboda tasirin abubuwan haɗin hydrogen, ƙarfin da ke tsakanin macromolecules yana da girma sosai, wanda zai haifar da babban narkewar enthalpy △H; a gefe guda, akwai zobba a cikin macromolecules cellulose. Kamar tsari, tsayayyen sarkar kwayoyin halitta ya fi girma, wanda zai haifar da ƙaramin narkewar entropy canji ΔS. Wadannan dalilai guda biyu suna sanya zafin narkakkar cellulose (= △H / △S) zai zama mafi girma, kuma yanayin bazuwar cellulose yana da ɗan ƙaramin ƙarfi. Saboda haka, lokacin da cellulose ya yi zafi zuwa wani zafin jiki, zaruruwa za su bayyana Al'amarin da cewa cellulose ya lalace kafin ya fara narkewa, don haka, sarrafa kayan cellulose ba zai iya amfani da hanyar narkar da farko ba sannan a yi gyare-gyare.

03. Muhimmancin gyare-gyaren cellulose

Tare da raguwar albarkatun burbushin halittu sannu a hankali da kuma ƙara munanan matsalolin muhalli da ke haifar da ɓarna na fiber yadudduka, haɓakawa da amfani da kayan fiber na halitta da ake sabunta su ya zama ɗaya daga cikin wurare masu zafi da mutane ke kula da su. Cellulose shine mafi yawan albarkatun halitta da ake sabunta su a yanayi. Yana da kyawawan kaddarorin irin su hygroscopicity mai kyau, antistatic, ƙarfin iska mai ƙarfi, rini mai kyau, sawa mai daɗi, sauƙin sarrafa yadi, da biodegradability. Yana da halayen da ba za a iya kwatanta su da filayen sinadarai ba. .

Kwayoyin salula na cellulose sun ƙunshi adadi mai yawa na ƙungiyoyin hydroxyl, waɗanda suke da sauƙi don samar da haɗin gwiwar intramolecular da intermolecular hydrogen, kuma suna bazuwa a yanayin zafi ba tare da narkewa ba. Duk da haka, cellulose yana da kyakkyawar amsawa, kuma haɗin haɗin hydrogen na iya lalacewa ta hanyar gyare-gyaren sinadarai ko aikin grafting, wanda zai iya rage yawan narkewa. A matsayin samfuran masana'antu iri-iri, ana amfani dashi sosai a cikin yadi, rabuwar membrane, robobi, taba da sutura.

04. Cellulose etherification gyara

Cellulose ether wani nau'i ne na cellulose wanda aka samo 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. Ana amfani da shi a abinci, magani, yin takarda, fenti, kayan gini, da sauransu.

Etherification na cellulose shine jerin abubuwan da aka samo ta hanyar amsawar ƙungiyoyin hydroxyl akan sarkar kwayoyin halitta ta cellulose tare da alkylating a ƙarƙashin yanayin alkaline. Yin amfani da ƙungiyoyin hydroxyl yana rage adadin haɗin haɗin hydrogen na intermolecular don rage ƙarfin intermolecular, ta haka inganta yanayin zafi na cellulose, inganta aikin aiki na kayan aiki, kuma a lokaci guda rage ƙwayar narkewar cellulose.

Misalai na tasirin gyare-gyaren etherification akan sauran ayyukan cellulose:

Yin amfani da auduga mai ladabi a matsayin ainihin albarkatun ƙasa, masu bincike sunyi amfani da tsari na etherification na mataki daya don shirya hadaddun ether na carbonoxymethyl hydroxypropyl cellulose tare da amsa uniform, high danko, mai kyau acid juriya da gishiri juriya ta hanyar alkalization da etherification halayen. 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 monovalent da salts divalent da kyakkyawan juriya na acid.

05. Haƙiƙa na gyare-gyaren etherification na cellulose

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