Qhov Tseem Ceeb - Ethylene Glycol vs Polyethylene Glycol
Ethylene glycol thiab polyethylene glycol yog ob tug tswv cuab tseem ceeb ntawm tsev neeg glycol. Qhov sib txawv tseem ceeb ntawm ethylene glycol thiab polyethylene glycol yog lawv cov qauv tshuaj. Ethylene glycol yog ib qho yooj yim linear molecule, hos polyethylene glycol yog cov khoom siv polymeric. Tsis tas li ntawd, ob qho tib si ntawm cov tebchaw no yog kev lag luam tseem ceeb heev thiab siv rau ntau daim ntawv thov.
YEthylene Glycol yog dab tsi?
IUPAC lub npe ntawm ethylene glycol yog ethane-1, 2-diol, thiab nws cov mis molecular yog (CH 2 OH) 2 Nws yog ib qho organic compound uas tuaj yeem siv los ua cov khoom siv raw los tsim polyester fibers thiab antifreeze formulations. Nws yog ib qho tsis muaj ntxhiab, tsis muaj xim, qab zib-tasting viscous dihydroxy cawv. Ethylene glycol yog tshuaj lom me ntsis yog tias noj. Nws yog glycol uas muaj ntau tshaj plaws thiab yog cov khoom lag luam tsim tawm hauv ntau. Nws muaj ntau daim ntawv thov kev lag luam; Nws yog siv los ua cov tshuaj tua kab mob hauv cov kua dej hydraulic thiab hauv kev tsim cov dynamites qis thiab cov resins.
YPolythene Glycol yog dab tsi?
Polyethylene glycol (PEG) yog cov khoom siv polymeric, thiab nws yog siv rau ntau qhov chaw xws li tshuaj lom neeg, tshuaj lom neeg, kev kho mob, kev lag luam thiab kev lag luam. Nws tseem hu ua polyethylene oxide (PEO) lossis polyoxyethylene (POE), nyob ntawm nws qhov hnyav molecular. Nws cov qauv feem ntau sau ua H−(O−CH2−CH2)n− OH. PEG yog cov kua ntshiab los yog dej-soluble dawb cov khoom uas muaj ntxhiab tsw.
Qhov txawv ntawm Ethylene Glycol thiab Polythene Glycol yog dab tsi?
Molecular Formula
Ethylene Glycol: Ethylene glycol yog diol nrog cov qauv molecular (CH 2-OH)2.
Polythene Glycol: Cov mis mos molecular ntawm PEG yog (C 2H 4O)n+1 H2O thiab nws cov qauv qauv qhia raws li hauv qab no.
Production:
Ethylene Glycol: Ethylene yog cov tshuaj lom neeg tseem ceeb uas siv los tsim ethylene glycol. Thaum lub sijhawm txheej txheem no, ethylene oxide yog tsim los ua ib qho nruab nrab, thiab tom qab ntawd nws tshwm sim nrog dej los tsim ethylene glycol.
C2H4O + H2O → HO–CH 2CH2–OH
Ob cov kua qaub thiab cov hauv paus tuaj yeem siv los ua cov tshuaj tiv thaiv no. Tsis tas li ntawd, cov tshuaj tiv thaiv tshwm sim ntawm nruab nrab pH nyob rau hauv siab kub heev. Cov txiaj ntsig siab (90%) tuaj yeem tau txais thaum cov tshuaj tiv thaiv tshwm sim ntawm acidic lossis nruab nrab pH, thaum muaj cov dej ntau dhau.
Polythene Glycol: Cov tshuaj tiv thaiv ntawm ethylene oxide nrog dej, ethylene glycol lossis ethylene glycol oligomers tsim polyethylene glycol. Ob qho acidic thiab yooj yim catalysts yog siv los ua kom cov tshuaj tiv thaiv no. Cov tshuaj tiv thaiv ntawm ethylene glycol thiab nws cov oligomers yog qhov zoo dua li dej. Qhov ntev ntawm cov saw hlau polymer nyob ntawm qhov piv ntawm cov reactants. Lub tshuab polymerization tuaj yeem ua cationic lossis anionic polymerization nyob ntawm hom catalyst.
HOCH2CH2OH + n(CH2CH 2O) → HO(CH2CH2O)n+1 H
Siv:
Ethylene Glycol: Ethylene glycol feem ntau yog siv hauv cov tshuaj tiv thaiv kab mob thiab ua cov khoom siv raw hauv kev tsim cov polyesters xws li polyethylene terephthalate (PET) hauv kev lag luam yas. Ethylene glycol tuaj yeem pab txhawb kev hloov pauv cua sov hauv tsheb thiab cov tshuab ua kua txias. Nws kuj tseem siv rau hauv cov dej txias cua txias.
Polythene Glycol: Polythene glycol muaj cov tshuaj toxicity tsawg thiab yog li nws yog siv los ua cov txheej lubricating rau ob qho tib si aqueous thiab non-aqueous ib puag ncig. Nws kuj yog siv los ua ib qho polar nyob ruaj khov theem hauv cov roj chromatography thiab ua cov kua dej hloov hluav taws xob hauv cov tshuab hluav taws xob. PEG yog lub hauv paus rau ntau daim tawv nqaij cream thiab tus kheej lubricants. Nws yog siv nyob rau hauv ib tug xov tooj ntawm cov tshuaj txhuam hniav raws li ib tug dispersant thiab raws li ib tug anti-foaming tus neeg sawv cev nyob rau hauv cov zaub mov muaj daim ntaub ntawv.
