Ulwazi lweekhemikhali inkcazo kunye nomahluko phakathi kwefayibha, iselilulose kunye ne-cellulose ether

Ifayibha:

Ifayibha, kwimeko yekhemistri kunye nesayensi yezinto, ibhekisa kudidi lwezinto ezibonakaliswa bulwakhiwo lwazo olude, olufana nomsonto. Ezi zinto zenziwe ziipolymers, ezingamamolekyuli amakhulu ezenziwe ngeeyunithi eziphindaphindayo ezibizwa ngokuba ziimonomers. Iifayibha zinokuba zendalo okanye zenziwe, kwaye zisetyenziswa kakhulu kumashishini ahlukeneyo kuquka amalaphu, izinto ezidityanisiweyo, kunye ne-biomedicine.

Iifayibha zendalo zivela kwizityalo, kwizilwanyana, okanye kwiiminerali. Imizekelo ibandakanya umqhaphu, uboya, isilika, kunye ne-asbestos. Iifayibha zokwenziwa, kwelinye icala, zenziwa ngezinto zeekhemikhali ngokusebenzisa iinkqubo ezifana ne-polymerization. I-nylon, i-polyester, kunye ne-acrylic zimizekelo eqhelekileyo yeefayibha zokwenziwa.

Kwicandelo lekhemistri, igama elithi "ifayibha" lidla ngokubhekisa kwisici solwakhiwo lwento kunokuba libhekisele kwisakhiwo sayo seekhemikhali. Iifayibha zibonakaliswa yi-aspect ratio yazo ephezulu, oko kuthetha ukuba zinde kakhulu kunokuba zibanzi. Esi sakhiwo side sinikezela ngeempawu ezifana namandla, ukuguquguquka, kunye nokuqina kwinto, okwenza iifayibha zibe yimfuneko kwiindlela ezahlukeneyo zokusetyenziswa ukusuka kwimpahla ukuya ekuqinisweni kwezinto ezidityanisiweyo.

Iseli:

I-Celluloseyi-polysaccharide, uhlobo lwe-carbohydrate oluqulunqwe ziintambo ezinde zeemolekyuli zeswekile. Yeyona polymer yendalo ininzi kakhulu eMhlabeni kwaye isebenza njengesakhi solwakhiwo kwiindonga zeseli zezityalo. Ngokwekhemikhali, i-cellulose ineeyunithi eziphindaphindayo zeglucose ezidityaniswe kunye ziibhondi ze-β-1,4-glycosidic.

Ulwakhiwo lwe-cellulose lune-fibrous kakhulu, kwaye iimolekyuli ze-cellulose nganye zizihlanganisa zibe zii-microfibrils ezihlangana ngakumbi ukuze zenze izakhiwo ezinkulu ezifana nee-fiber. Ezi fibers zibonelela ngenkxaso yesakhiwo kwiiseli zezityalo, zinika ukuqina namandla. Ukongeza kwindima yayo kwizityalo, i-cellulose ikwayinxalenye ephambili ye-fiber yokutya efumaneka kwiziqhamo, imifuno, kunye neenkozo. Abantu abanazo ii-enzymes ezifunekayo ukuqhekeza i-cellulose, ngoko ke idlula kwinkqubo yokugaya ukutya ingaphazanyiswa, inceda ekugayweni kokutya kwaye ikhuthaze impilo yamathumbu.

I-Cellulose inezicelo ezininzi zoshishino ngenxa yobuninzi bayo, ukuhlaziywa kwayo, kunye neempawu ezinqwenelekayo ezifana nokubola kwezinto eziphilayo, ukuhambelana kwezinto eziphilayo, kunye namandla. Isetyenziswa kakhulu ekuveliseni iphepha, amalaphu, izinto zokwakha, kunye ne-biofuels.

I-Ether yeSellulose:

Ii-ether ze-celluloseliqela leekhemikhali ezifumaneka kwi-cellulose ngokuguqulwa kweekhemikhali. Olu tshintsho lubandakanya ukungeniswa kwamaqela asebenzayo, anjenge-hydroxyethyl, i-hydroxypropyl, okanye i-carboxymethyl, kwi-cellulose backbone. Ii-cellulose ethers eziphumayo zigcina ezinye zeempawu ze-cellulose ngelixa zibonisa iimpawu ezintsha ezinikwa ngamaqela asebenzayo ongezelelweyo.

Omnye wemiba ephambili phakathi kwe-cellulose kunye ne-cellulose ethers ikwiimpawu zazo zokunyibilika. Nangona i-cellulose inganyibiliki emanzini kwaye uninzi lwe-organic solvents, i-cellulose ethers zihlala zinyibilika emanzini okanye zibonisa ukunyibilika okuphucukileyo kwi-organic solvents. Oku kunyibilika kwenza i-cellulose ethers ibe zizinto ezisebenziseka ngeendlela ezahlukeneyo kunye noluhlu olubanzi lwezicelo kumashishini afana namayeza, ukutya, izinto zokuthambisa, kunye nokwakha.

Imizekelo eqhelekileyo yee-ether ze-cellulose ibandakanya i-methyl cellulose (MC), i-hydroxypropyl cellulose (HPC), kunye ne-carboxymethyl cellulose (CMC). Ezi compounds zisetyenziswa njenge-thickeners, binders, stabilizers, kunye nee-agents ezenza ifilimu kwiifomyula ezahlukeneyo. Umzekelo, i-CMC isetyenziswa kakhulu kwiimveliso zokutya njenge-agent yokutyeba kunye ne-emulsifier, ngelixa i-HPC isetyenziswa kwiifomyula zamayeza zokukhupha amayeza alawulwayo.

ifayibha ibhekisa kwizinto ezinesakhiwo eside, esifana nomsonto, i-cellulose yi-polymer yendalo efumaneka kwiindonga zeeseli zezityalo, kwaye ii-cellulose ethers zizinto eziguqulwe ngokweekhemikhali ze-cellulose ezinezicelo ezahlukeneyo zoshishino. Ngelixa i-cellulose ibonelela ngesakhelo sesakhiwo sezityalo kwaye isebenza njengomthombo wefayibha yokutya, ii-cellulose ethers zibonelela ngokunyibilika okuphuculweyo kwaye zisetyenziswa kumacandelo amaninzi emizi-mveliso ngenxa yeempawu zazo ezizodwa.