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Abstract

The shear viscosity of fluids in general, and polymer melts in particular, depends on temperature, pressure, and shear rate. Although the effects of temperature and shear rate have been studied extensively for a large number of polymer types, only recently methods have been devised to study the effect of pressure. As a result of these studies, it has been found that the effect of pressure on the shear viscosity of polymer melts is quite significant. Furthermore, the effect of viscous heating on the determination of viscosity from capillary measurements has been recognized, and some attempts have been made to make corrections for this effect (1, 2).

List of Symbols

Cv

specific heat at constant volume

L

total length of capillary

LD

length of capillary over which developed flow exists

LT

length of capillary over which hypothetical isothermal flow exists

P

pressure

ΔPd, P

pressure drop over developed flow region

ΔPtotal

total pressure drop

ΔPacc

average temperature rise of the melt expressed as a pressure drop

ΔPe

pressure drop in the entrance region

R

capillary radius

r

radial coordinate

T

temperature

T

average temperature of the melt

Ta

temperature of the barrel and capillary surface

Q

volumetric flow rate

qr

radial heat conduction flux at position r

qR

radial heat conduction flux at the capillary wall

τrz

shear stress

τw

shear stress at the capillary wall

\(\mathop \gamma \limits^. \)

shear rate

\([tex]\mathop {{\gamma _w}}\limits^ \cdot [/tex]\)w

shear rate at the capillary wall

ϱ

density of the melt

η

viscosity of polymer melt

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References

  1. 1).
    Garrard, J. E. and W. Philippoff, Proc. Fourth Int. Congr. Rheol. 4, 77 (1963).Google Scholar
  2. 2).
    Cheng, D. C. H., Proc. Fifth Int. Congr. Rheol. 1, 483 (1969).Google Scholar
  3. 3).
    Westover, R. F. and B. Maxwell, SPE Journal 13, 27 (1957).Google Scholar
  4. 4).
    Semjownow, von V., Rheol. Acta 2, 138 (1962).CrossRefGoogle Scholar
  5. 5).
    Ramsteiner, von F., Rheol. Acta 9, 374 (1970).CrossRefGoogle Scholar
  6. 6).
    Duvdevani, I. J. and I. Klein, SPE Journal 23, 41 (1967).Google Scholar
  7. 7).
    Choi, S. Y. and N. Nakajima, Fifth Int. Congr. Rheol. 4, 287 (1970).Google Scholar
  8. 8).
    Penwell, R. C, R. S. Porter, and S. Middleman, J. Polym. Sci. A-2, 9, 731 (1971).CrossRefGoogle Scholar
  9. 9).
    Bagley, E. B., J. Appl. Phys. 28, 624 (1957).ADSCrossRefGoogle Scholar
  10. 10).
    Bogue, D. C., Ind. Eng. Chem. 51, 874 (1959).CrossRefGoogle Scholar
  11. 11).
    Collins, M. and W. R. Schowalter, Amer. Inst. Chem. Eng. J. 9, 98 (1969).CrossRefGoogle Scholar
  12. 12).
    Carslaw, H. S. and J.C. Jaeger, Conduction of Heat in Solids, p. 339 (London 1959).Google Scholar
  13. 13).
    Bird, R. B., SPE Journal 11, 35 (1955).Google Scholar
  14. 14).
    Middleman, S., The Flow of High Polymers, p. 15 (London-New York 1968).Google Scholar
  15. 15).
    Williams, M. R., R. F. Landel, and J. D. Ferry, J. Amer. Chem. Soc. 77, 3701 (1955).CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1975

Authors and Affiliations

  • M. R. Kamal
    • 1
  • H. Nyun
    • 1
  1. 1.Department of Chemical EngineeringMcGill UniversityMontrealCanada

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