ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Intrinsic viscosities of polymers are most often estimated using the Huggins equation, which relates the quotient ηsp/c to intrinsic viscosity and concentration c. It is shown that when this method is used, the error structure is distorted by the presence of concentration in the quotient. The result is that when dilution series experiments are analyzed, the estimates are ordinarily poorer the more dilutions are made. A rearrangement of the Huggins equation is introduced which allows precise estimation from any experiment. It is also shown that dilution series experiments with more than three different concentrations including that of the pure solvent are inefficient by any method of analysis, and convenient experiments which may be considered practical optima are described. When they are used the conventional analysis is restored to full efficiency. Design and analysis of experiments where there is important uncertainty in polymer concentration are also studied.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1979.070241002
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