Chidziwitso cha mankhwala tanthauzo ndi kusiyana kwa ulusi, cellulose ndi cellulose ether

Ulusi:

Ulusi, pankhani ya sayansi ya chemistry ndi zinthu, amatanthauza gulu la zinthu zomwe zimadziwika ndi kapangidwe kake kautali, kofanana ndi ulusi. Zinthuzi zimapangidwa ndi ma polima, omwe ndi mamolekyu akuluakulu opangidwa ndi mayunitsi obwerezabwereza otchedwa monomers. Ulusi ukhoza kukhala wachilengedwe kapena wopangidwa, ndipo umagwiritsidwa ntchito kwambiri m'mafakitale osiyanasiyana kuphatikiza nsalu, zinthu zophatikizika, ndi biomedicine.

Ulusi wachilengedwe umachokera ku zomera, nyama, kapena mchere. Zitsanzo zikuphatikizapo thonje, ubweya, silika, ndi asbestos. Ulusi wopangidwa, kumbali ina, umapangidwa kuchokera ku zinthu za mankhwala kudzera mu njira monga polymerization. Nayiloni, polyester, ndi acrylic ndi zitsanzo zodziwika bwino za ulusi wopangidwa.

Mu sayansi ya chemistry, mawu oti "ulusi" nthawi zambiri amatanthauza kapangidwe ka zinthu osati kapangidwe kake ka mankhwala. Ulusi umadziwika ndi chiŵerengero chawo chapamwamba, zomwe zikutanthauza kuti ndi wautali kwambiri kuposa momwe ulili m'lifupi. Kapangidwe kameneka kameneka kamapereka mphamvu monga mphamvu, kusinthasintha, ndi kulimba kwa zinthuzo, zomwe zimapangitsa ulusi kukhala wofunikira pazinthu zosiyanasiyana kuyambira zovala mpaka zolimbitsa zinthu zophatikizika.

Selosi:

Selosindi polysaccharide, yomwe ndi mtundu wa chakudya chopangidwa ndi maunyolo ataliatali a mamolekyu a shuga. Ndi polima wachilengedwe wochuluka kwambiri padziko lonse lapansi ndipo umagwira ntchito ngati gawo la kapangidwe ka makoma a maselo a zomera. Mwa mankhwala, cellulose imakhala ndi mayunitsi obwerezabwereza a shuga olumikizidwa pamodzi ndi ma bond a β-1,4-glycosidic.

Kapangidwe ka cellulose ndi kaulusi wambiri, ndipo mamolekyu a cellulose amalumikizana kukhala ma microfibrils omwe amaphatikizana kuti apange mapangidwe akuluakulu monga ulusi. Ulusi uwu umathandizira kapangidwe ka maselo a zomera, zomwe zimawapatsa kulimba ndi mphamvu. Kuwonjezera pa ntchito yake m'zomera, cellulose ndi gawo lalikulu la ulusi wazakudya womwe umapezeka mu zipatso, ndiwo zamasamba, ndi tirigu. Anthu alibe ma enzyme ofunikira kuti aswe cellulose, kotero imadutsa m'mimba momwe ilili yonse, kuthandiza kugaya chakudya ndikulimbikitsa thanzi la matumbo.

Cellulose imagwiritsidwa ntchito m'mafakitale ambiri chifukwa cha kuchuluka kwake, kusinthika kwake, komanso zinthu zofunika monga kuwonongeka kwa zinthu zachilengedwe, kuyanjana ndi zinthu zachilengedwe, komanso mphamvu zake. Imagwiritsidwa ntchito kwambiri popanga mapepala, nsalu, zipangizo zomangira, ndi mafuta a zomera.

Cellulose Ether:

Ma ether a cellulosendi gulu la mankhwala ochokera ku cellulose kudzera mu kusintha kwa mankhwala. Kusintha kumeneku kumaphatikizapo kuyambitsa magulu ogwira ntchito, monga hydroxyethyl, hydroxypropyl, kapena carboxymethyl, pa msana wa cellulose. Ma cellulose ethers omwe amapezeka amasunga zina mwa makhalidwe abwino a cellulose pamene akuwonetsa makhalidwe atsopano omwe amaperekedwa ndi magulu ogwira ntchito owonjezera.

Kusiyana kwakukulu pakati pa ma cellulose ndi ma cellulose ethers kuli mu mphamvu zawo zosungunula. Ngakhale kuti cellulose sisungunuka m'madzi ndi zinthu zambiri zachilengedwe, ma cellulose ethers nthawi zambiri amasungunuka m'madzi kapena amasungunuka bwino m'zinthu zachilengedwe zachilengedwe. Kusungunuka kumeneku kumapangitsa kuti ma cellulose ethers akhale ndi zinthu zosiyanasiyana zomwe zimagwiritsidwa ntchito m'mafakitale monga mankhwala, chakudya, zodzoladzola, ndi zomangamanga.

Zitsanzo zodziwika bwino za ma ether a cellulose ndi monga methyl cellulose (MC), hydroxypropyl cellulose (HPC), ndi carboxymethyl cellulose (CMC). Mankhwalawa amagwiritsidwa ntchito ngati zothina, zomangira, zokhazikika, komanso zopangira filimu m'njira zosiyanasiyana. Mwachitsanzo, CMC imagwiritsidwa ntchito kwambiri muzakudya monga chothina komanso chopangira emulsifier, pomwe HPC imagwiritsidwa ntchito m'njira zopangira mankhwala kuti atulutse mankhwala olamulidwa.

Ulusi umatanthauza zinthu zokhala ndi kapangidwe kautali, kofanana ndi ulusi, cellulose ndi polima wachilengedwe womwe umapezeka m'makoma a maselo a zomera, ndipo ma ether a cellulose ndi zinthu zosinthidwa ndi mankhwala kuchokera ku cellulose zomwe zimagwiritsidwa ntchito m'mafakitale osiyanasiyana. Ngakhale kuti cellulose imapereka chimango cha kapangidwe ka zomera ndipo imagwira ntchito ngati gwero la ulusi wazakudya, ma ether a cellulose amapereka kusungunuka kwabwino ndipo amagwiritsidwa ntchito m'mafakitale osiyanasiyana chifukwa cha mawonekedwe awo apadera.