PTFE vs LDPE

Tsawg-density polyethylene (LDPE) yog ib qho thermoplastic ua los ntawm monomer ethylene.Nws yog thawj qib ntawm polyethylene, tsim nyob rau hauv 1933 los ntawm Imperial Chemical Industries (ICI) siv cov txheej txheem siab ntawm dawb radical polymerization.EPA kwv yees li 5.7% ntawm LDPE yog rov siv dua.Txawm hais tias muaj kev sib tw los ntawm cov polymers niaj hnub no, LDPE tseem yog qib yas tseem ceeb.

LDPE yog txhais los ntawm qhov ceev ntawm 0.910-0.940 g / cm3.Nws tsis yog reactive nyob rau hauv chav tsev kub, tshwj tsis yog los ntawm muaj zog oxidizing tus neeg sawv cev, thiab ib co kuab tshuaj ua rau o.Nws tuaj yeem tiv taus qhov kub ntawm 80 ° C tsis tu ncua thiab 95 ° C rau lub sijhawm luv luv.Ua nyob rau hauv translucent los yog opaque variations, nws yog heev saj zawg zog thiab tawv.

LDPE muaj ntau tshaj li HDPE, yog li nws cov intermolecular rog tsis muaj zog, nws lub zog tensile qis dua, thiab nws cov resilience siab dua.Tsis tas li ntawd, vim tias nws cov molecules tsis nruj nruj thiab tsis tshua muaj crystalline vim yog sab ceg, nws qhov ntom ntom qis dua.

PTFE yog ib qho thermoplastic polymer, uas yog cov khoom dawb ntawm chav tsev kub, nrog qhov ceev ntawm li 2200 kg / m3.Raws li DuPont, nws cov ntsiab lus melting yog 600 K (327 ° C; 620 ° F).[19]Nws tuav lub zog siab, toughness thiab nws tus kheej lubrication ntawm qhov kub qis mus rau 5 K (−268.15 ° C; −450.67 ° F), thiab ua tau zoo ntawm qhov kub siab tshaj 194 K (-79 ° C; -110 ° F).PTFE tau txais nws cov khoom los ntawm kev sib sau ua ke ntawm carbon-fluorine bonds, zoo li tag nrho cov fluorocarbons.Tsuas yog cov tshuaj uas paub tias cuam tshuam rau cov carbon-fluorine bonds yog cov hlau reactive zoo li cov hlau alkali, thiab nyob rau ntawm qhov kub siab dua kuj xws li hlau xws li txhuas thiab magnesium, thiab cov tshuaj fluorinating xws li xenon difluoride thiab cobalt (III) fluoride.

cov

Khoom siv:

PTFE:Cabling kev daws teeb meem; Tsis yog lubricated bearings; O-rings; Foob; Capacitors; Semiconductor manufacturing; Kub kub qhov hluav taws xob; Gaskets; Valve Cheebtsam.

LDPE:Cov tais thiab cov thawv ntim dav dav; Corrosion-resistant chaw ua hauj lwm; Qhov chaw ntawm lub computer hardware, xws li hard disk drives, screen cards, thiab optical disc drives.

Khoom Khoom

PTFE:Cov khoom zoo heev dielectric; Inertness rau feem ntau cov tshuaj; kub kub thiab tshuaj tiv thaiv; Tsis tshua muaj coefficient ntawm kev sib txhuam; Cov hluav taws xob zoo heev; xoom noo noo nqus; Resensitive rau lub zog zaus; Machinability.

LDPE:Tsis-reactive nyob rau hauv chav tsev kub; Muaj peev xwm tiv taus kub ntawm 80 ° C tsis tu ncua; Machinability.