6533b7d7fe1ef96bd12682ca
RESEARCH PRODUCT
false
Stoyko FakirovG. F. SchmidtE. W. Fischersubject
Diffractionchemistry.chemical_compoundEthylenechemistryAnnealing (metallurgy)ComonomerPolymer chemistryDiethylene glycolTriclinic crystal systemMole fractionPoly ethylenedescription
The density of crystals of poly(ethylene terephthalate), (PETP), Qc is checked by X-ray diffraction assuming a triclinic unit cell and the indices of reflections as found by Bunn. The following unit cell dimensions are found: a = 4,48A, b = 5,85A, c = 10,75 A, α = 99,5°, β = 118,4°, and γ = 111,2°. This gives the density Qc as 1,515g/cm3 which is about 4% higher than that reported by Bunn. Negligible differences in spacings for samples annealed at different temperatures (120°C–260°C) have been found. Only for an annealing temperature of 100°C the higher d-values lead to Qc = 1,484g/cm3. For undrawn PETP films annealed at 250°C the same value of Qc as for drawn PETP was obtained on the basis of Guinier X-ray patterns. No systematic variation of crystal plane spacings was found for drawn PETP fibers annealed at 220°C and containing mole fractions of 1,7 to 4,2% diethylene glycol, (2,2′-oxydiethanol), as comonomer.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1975-08-01 | Die Makromolekulare Chemie |