Formula cellulose. Tshuaj lub zog. Kev npaj, daim ntawv thov

Ua paub niaj hnub siv rau peb, uas yog ubiquitous nyob rau hauv peb lub neej txhua hnub, nws yuav tsis yooj yim sua xav txog tej yam tsis muaj kev siv ntawm cov organic tshuaj cov khoom. Ntev ua ntej tshuaj thwmsim Anselm Payá, raws li ib tug tshwm sim ntawm uas nws muaj peev xwm mus nrhiav tau thiab piav qhia txog nyob rau hauv 1838 ib tug polysaccharide uas tau txais lub npe "cellulose" (derived ntawm cov Fabkis cellulose thiab cov Latin cellula, lub ntsiab lus "cell txee dai khaub ncaws"), qhov no khoom teejtug uas yog ib yam khoom uas nquag siv nyob rau hauv ntau lawm tseem ceeb tshaj plaws tej yam.

Kev paub ntau zog ntawm lub sis plawv hniav tau coj mus rau ib tug ntau yam ntawm tej yam uas, ua rau nws cov hauv paus. Daim ntawv ntawm ntau yam qib, paperboard, yas qhov chaw thiab ntawm cov khoom cua fibers (acetate, viscose rayon, tooj liab-ammonia), polymer films, enamels thiab varnishes, detergents, khoom noj khoom haus additive (E460) thiab txawm smokeless hmoov yog khoom ntawm lub ntau lawm thiab ua ntawm sis plawv hniav.

Ntshiab cellulose yog ib tug dawb khoom nrog ib tug ncaj txaus nyiam zog, muaj zoo heev kuj mus rau ntau yam tshuaj thiab lub cev influences.

Xwm xaiv cellulose (cellulose) raws li lawv cov thawj lub tsev khoom. Nyob rau hauv cov nroj tsuag ntiaj teb no nws yog lub hauv paus rau ntawm phab ntsa ntawm cov ntoo thiab lwm yam ntau dua cov nroj tsuag. Nyob rau hauv lub purest daim ntawv ntawm lawm tab cellulose yog paj rwb noob plaub mos mos.

Lub cim thaj chaw ntawm no cov ntaub ntawv uas yog txiav txim los ntawm nws cov thawj qauv. cellulose mis muaj ib tug tag nrho cov ntaub ntawv (C6 H10 O5) n los ntawm uas peb pom ib tug qhia tau polymeric qauv. Rov qab ua dua ib tug lossis loj tus naj npawb ntawm cov sij hawm β-glucose residue muaj ib tug xav paub ntau dua saib ntawm yuav ua li cas - [C6 H7 O2 (OH) 3] -, yog kev cob cog rua rau hauv ib tug ntev linear molecule.

Molecular cellulose mis sij nws cov cim tshuaj zog los kom tiv thaiv corrosive tej kev kawm. Tsis tas li ntawd sis plawv hniav muaj ib tug high kuj los ua cua sov, txawm nyob rau hauv 200 degrees Celsius khoom tswj nws cov qauv thiab yog tsis pov tseg. Autoignition tshwm sim nyob rau ib tug kub ntawm 420 ° C.

Tsis muaj tsawg txaus nyiam cellulose nyob rau hauv lawv lub zog. Cov yam ntxwv mis ntawm cellulose nyob rau hauv daim ntawv ntawm ntev strands muaj los ntawm 300 mus 10,000 zib units muaj tsis muaj sab ceg, lom zem ntau thiab txiav txim seb lub siab stability ntawm no substance. Formula glucose qhia tau hais tias yuav ua li cas ib tug plurality ntawm hydrogen bonds ntxeev siab rau cellulose fibers tsis tau tsuas yog siab txhua yam dag lub zog, tab sis kuj siab elasticity. Cov qhabnias ntawm analytical ua ib tug plurality ntawm tshuaj thwmsim thiab kev tshawb fawb yog tus creation ntawm ib tug qauv ntawm cellulose macromolecules. Nws yog ib tug nruj heev muab kauv nyob rau hauv cov kauj ruam 2-3 ntawm theem qeg, uas yog stabilized vim intramolecular hydrogen bonds.

Tsis cellulose mis thiab nws cov degree ntawm polymerization yog ib tug yooj yim cov yam ntxwv rau ntau yam. Yog li nyob rau hauv cov nqaij nyoos paj rwb nce mus txog lub xov tooj ntawm glucosidic residues 2500-3000, lub lim paj rwb - los ntawm 900 mus rau 1000, lim ntoo sis plawv hniav muaj qhov taw qhia 800-1000, regenerating lub cellulose nyob rau hauv lawv cov xov tooj yog txo mus rau 200-400, thiab cellulose acetate nyob rau hauv ib tug muaj nws yog hom twg los ntawm 150 rau 270 "links" nyob rau hauv lub molecule.

A khoom ua cellulose yog cog khoom, feem ntau yog cov ntoo. Cov yooj yim txheej txheem zus tau tej cov ntoo tej daim nrog rau ntau yam pulping tshuaj, ua raws li los ntawm purification, kom qhuav thiab txiav cov khoom tiav.

Tom ntej kev kho mob ntawm cellulose ua rau nws tau mus nrhiav tau ib tug ntau yam ntawm cov ntaub ntawv nrog qhov kev kawm lub cev thiab tshuaj thaj chaw uas tso cai rau yuav tsim ib tug ntau yam ntawm cov khoom, tsis muaj uas lub neej uas niaj hnub tus txiv neej yog ib qho nyuaj rau xav txog tej yam. Lub cim mis ntawm cellulose, tom tshuaj thiab lub cev kev kho mob, los ua lub hauv paus rau zus tau tej cov ntaub ntawv uas yog nws nyob rau hauv cov xwm, uas lawv yuav tsum tau lug siv nyob rau hauv cov tshuaj ua lag luam, cov tshuaj thiab lwm yam liaj teb ntawm tib neeg kev ua si.