"Intrinsic viscosity measurements were performed on linear polyethylene (Marlex 6009) in decalin at 135ºC and in diphenyl ether at 163.9ºC. Molecular weights ranging from 3x10³ to 35x10⁴ were studied. It was found that for linear polyethylene of molecular weight up to 35x10⁴, the tedious intrinsic viscosity measurement could be replaced by inherent viscosity measurement at a concentration of 0.1 grams per deciliter. The effect of shear on viscosities measured in decalin increased as the molecular weight of the sample increased. The shear rate effects on intrinsic viscosities were negligible. On the other hand, the shear rate effect on the Huggins' constant was surprisingly high considering the small shear rate effect on viscosities but still negligible. The validity of the Huggins equation was tested. It was found that the equation holds to [η]C≈0.75 or ηrel <1.9 for all polyethylene samples except the highest molecular weight sample (35x10⁴). For samples of Mw=6,200 to 145,000, the Huggins' constants were sensitive to the molecular weight of the sample in poor solvents. The Mark-Houwink expression for the linear polyethylene samples (0.62w x10⁻⁴ <35.0) in decalin at 135ºC was: [η]=5.72x10⁻⁴Mw0.70. In diphenyl ether at 163.9ºC, a theta solvent, [n]Θ =26.1x10⁻⁴ Mw0.5 was observed for samples (0.62w x 10⁴<5.8). The dimensionless ratio (r[overscore 2 over o])/nℓ² calculated from the intrinsic viscosity of samples in the Θ solvent was 6.06, and a value 1.03x10⁻¹⁶ for (r[2 over o])/M was obtained for all the samples. The values are close to the values obtained by Chiang and support the theoretical calculation done by Hoover and Nagai"--Abstract, page iii.
Mayhan, Kenneth G.
Zakin, J. L.
Venable, Raymond L., 1935-2008
Chemical and Biochemical Engineering
M.S. in Chemical Engineering
University of Missouri--Rolla. Graduate Center for Materials Research
University of Missouri--Rolla
xiii, 62 pages
© 1971 Joseph Shing Chiang, All rights reserved.
Thesis - Open Access
Polyethylene -- Viscosity -- Mathematical models
Polyethylene -- Viscosity -- Measurement
Polyethylene -- Testing
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Chiang, Joseph Shing, "Intrinsic viscosities of linear polyethylene" (1971). Masters Theses. 7209.