Kapangidwe kabwino ka awiriethers a cellulosezaperekedwa mu Zithunzi 1.1 ndi 1.2. Mphesa iliyonse ya β-D yomwe yaphwanyidwa ndi molekyulu ya cellulose
Gawo la shuga (gawo lobwerezabwereza la cellulose) limasinthidwa ndi gulu limodzi la ether lililonse pamalo a C(2), C(3) ndi C(6), mwachitsanzo mpaka atatu
gulu la ether. Chifukwa cha kukhalapo kwa magulu a hydroxyl, ma macromolecule a cellulose ali ndi ma hydrogen bond amkati mwa mamolekyulu ndi pakati pa mamolekyulu, omwe ndi ovuta kusungunuka m'madzi.
Ndipo n'kovuta kusungunuka pafupifupi m'zinthu zonse zachilengedwe. Komabe, pambuyo pa etherification ya cellulose, magulu a ether amalowetsedwa mu unyolo wa mamolekyu,
Mwanjira imeneyi, ma hydrogen bonds mkati ndi pakati pa mamolekyu a cellulose amawonongeka, ndipo hydrophilicity yake imakulanso, kotero kuti kusungunuka kwake kukhoza kukwera.
Pakati pawo, Chithunzi 1.1 ndi kapangidwe kake ka mayunitsi awiri a anhydroglucose a cellulose ether molecular chain, R1-R6=H
kapena zinthu zolowa m'malo mwa organic. 1.2 ndi chidutswa cha carboxymethyl hydroxyethyl cellulose molecular chain, mlingo wa kusintha kwa carboxymethyl ndi 0.5,4
Mlingo wosinthira wa hydroxyethyl ndi 2.0, ndipo digiri yosinthira molar ndi 3.0.
Pa chinthu chilichonse cholowa m'malo mwa cellulose, kuchuluka konse kwa etherification yake kumatha kufotokozedwa ngati digiri ya kusintha (DS). Yopangidwa ndi ulusi
Kuchokera ku kapangidwe ka molekyulu yayikulu, tingaone kuti mulingo wa kusintha umachokera pa 0-3. Ndiko kuti, mphete iliyonse ya anhydroglucose ya cellulose
, chiwerengero chapakati cha magulu a hydroxyl chomwe chinalowetsedwa m'malo mwa magulu otenthetsa a wothandizira wotenthetsa. Chifukwa cha gulu la hydroxyalkyl la cellulose, cholowa chake m'malo mwake
Kuthira kwa ether kuyenera kuyambitsidwanso kuchokera ku gulu latsopano la hydroxyl laulere. Chifukwa chake, kuchuluka kwa kusintha kwa mtundu uwu wa cellulose ether kumatha kufotokozedwa mu ma moles.
digiri ya kusintha (MS). Chomwe chimatchedwa digiri ya kusintha kwa molar chimasonyeza kuchuluka kwa mankhwala ophera omwe amawonjezeredwa ku gawo lililonse la anhydroglucose la cellulose.
Kulemera kwapakati kwa ma reactants.
1 Kapangidwe kake ka gawo la shuga
Zidutswa ziwiri za unyolo wa maselo a ether
1.2.2 Gulu la ma ether a cellulose
Kaya ma ether a cellulose ndi ma ether amodzi kapena ma ether osakanikirana, makhalidwe awo ndi osiyana pang'ono.
Ngati gulu la hydroxyl la mphete ya unit lilowedwa m'malo ndi gulu lokonda hydrophilic, chinthucho chikhoza kukhala ndi digiri yocheperako yosinthira malinga ndi digiri yocheperako yosinthira.
Ili ndi madzi osungunuka pang'ono; ngati yasinthidwa ndi gulu losakonda madzi, mankhwalawa amakhala ndi madzi osinthika pang'ono pokhapokha ngati madzi osinthidwawo ali ochepa.
Zinthu zosungunuka m'madzi, zomwe sizimalowetsedwa m'malo mwa cellulose etherification, zimatha kudzikundikira m'madzi, kapena kusungunuka m'madzi osasungunuka kwambiri.
pakati.
Malinga ndi mitundu ya zinthu zolowa m'malo, ma ether a cellulose akhoza kugawidwa m'magulu atatu: magulu a alkyl, monga methyl cellulose, ethyl cellulose;
Ma hydroxyalkyls, monga hydroxyethyl cellulose, hydroxypropyl cellulose; ena, monga carboxymethyl cellulose, ndi zina zotero. Ngati ionization yachitika
Kugawa, ma ether a cellulose akhoza kugawidwa m'magulu awa: ma ionic, monga carboxymethyl cellulose; osakhala ionic, monga hydroxyethyl cellulose; osakaniza
mtundu, monga hydroxyethyl carboxymethyl cellulose. Malinga ndi gulu la kusungunuka, cellulose ikhoza kugawidwa m'magulu awa: yosungunuka m'madzi, monga carboxymethyl cellulose,
Hydroxyethyl cellulose; yosasungunuka m'madzi, monga methyl cellulose, ndi zina zotero.
1.2.3 Katundu ndi ntchito za ma ether a cellulose
Cellulose ether ndi mtundu wa chinthu chomwe chimagwiritsidwa ntchito pambuyo pa kusintha kwa etherification ya cellulose, ndipo ether ya cellulose ili ndi zinthu zambiri zofunika kwambiri.
Ili ndi mphamvu zabwino zopangira filimu; monga phala losindikizira, imasungunuka bwino madzi, imakhuthala, imasunga madzi komanso imakhala yokhazikika;
5
Ether wamba ndi wopanda fungo, si poizoni, ndipo umagwirizana bwino ndi zinthu zina. Pakati pawo, carboxymethyl cellulose (CMC) ili ndi "industrial monosodium glutamate"
dzina laukazitape.
1.2.3.1 Kupanga mafilimu
Mlingo wa ether wa cellulose ether umakhudza kwambiri momwe imapangira filimu monga mphamvu yopangira filimu ndi mphamvu yolumikizirana.
Chifukwa cha mphamvu zake zabwino zamakanika komanso kugwirizana bwino ndi ma resin osiyanasiyana, ingagwiritsidwe ntchito m'mafilimu apulasitiki, zomatira ndi zinthu zina.
kukonzekera zinthu.
1.2.3.2 Kusungunuka
Chifukwa cha kukhalapo kwa magulu ambiri a hydroxyl pa mphete ya unit ya glucose yokhala ndi mpweya, ma ether a cellulose ali ndi kusungunuka kwabwino kwa madzi.
Kutengera ndi cholowa m'malo cha cellulose ether ndi kuchuluka kwa cholowa m'malo, palinso kusankha kosiyana kwa zosungunulira zachilengedwe.
1.2.3.3 Kukhuthala
Cellulose ether imasungunuka mu yankho lamadzimadzi mu mawonekedwe a colloid, pomwe kuchuluka kwa polymerization ya cellulose ether kumatsimikiza cellulose
Kukhuthala kwa yankho la etha. Mosiyana ndi madzi a Newtonian, kukhuthala kwa yankho la etha la cellulose kumasintha ndi mphamvu yometa, ndipo
Chifukwa cha kapangidwe kameneka ka macromolecules, kukhuthala kwa yankho kudzawonjezeka mofulumira ndi kuwonjezeka kwa kuchuluka kwa ether ya cellulose, komabe kukhuthala kwa yankholo.
Kukhuthala kumachepanso mofulumira kutentha kukakwera [33].
1.2.3.4 Kuwonongeka
Njira yothetsera ether ya cellulose yomwe imasungunuka m'madzi kwa kanthawi idzakulitsa mabakiteriya, motero imapanga mabakiteriya a enzyme ndikuwononga gawo la ether ya cellulose.
Ma bond a glucose omwe sanasinthidwe ndi omwe ali pafupi, potero amachepetsa kuchuluka kwa mamolekyulu a macromolecule. Chifukwa chake, ma cellulose ethers
Kusunga madzi m'thupi kumafuna kuwonjezera zinthu zina zotetezera.
Kuphatikiza apo, ma ether a cellulose ali ndi zinthu zina zambiri zapadera monga ntchito ya pamwamba, ntchito ya ionic, kukhazikika kwa thovu ndi zowonjezera.
Kuchita kwa gel. Chifukwa cha izi, ma ether a cellulose amagwiritsidwa ntchito popanga nsalu, kupanga mapepala, sopo wopangira, zodzoladzola, chakudya, mankhwala,
Amagwiritsidwa ntchito kwambiri m'magawo ambiri.
1.3 Chiyambi cha zipangizo zopangira zomera
Kuchokera ku chiwonetsero cha 1.2 cellulose ether, zitha kuwoneka kuti zopangira zokonzekera cellulose ether makamaka ndi thonje cellulose, ndipo chimodzi mwazomwe zili munkhaniyi
Ndi kugwiritsa ntchito cellulose yotengedwa kuzinthu zopangira zomera kuti ilowe m'malo mwa thonje cellulose kuti ikonze cellulose ether. Izi ndi mwachidule zomwe zafotokozedwa pa chomerachi.
zinthu.
Pamene zinthu zodziwika bwino monga mafuta, malasha ndi gasi wachilengedwe zikuchepa, kupanga zinthu zosiyanasiyana zochokera pa zinthu zimenezi, monga ulusi wopangidwa ndi mafilimu a ulusi, kudzachepanso kwambiri. Chifukwa cha chitukuko chopitilira cha anthu ndi mayiko padziko lonse lapansi (makamaka
Ndi dziko lotukuka lomwe limayang'anitsitsa vuto la kuipitsidwa kwa chilengedwe. Cellulose yachilengedwe imatha kuwonongeka ndi kuyanjana kwa chilengedwe.
Pang'onopang'ono idzakhala gwero lalikulu la zinthu zopangidwa ndi ulusi.
Nthawi yotumizira: Sep-26-2022