ISSN:
0021-8995
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
,
Physik
Notizen:
Flow injection analysis, often used for determination of diffusion coefficients of nonpolymeric substances, has now been applied to the characterization of pauci- and polydisperse polymers in solution. A relative method was found useful for obtaining moderate quality evaluations of diffusion coefficients and related parameters of polymers. The width at half-height W1/2 of the trace peak is found to be proportional to the number average molecular weight M̄n of pauci- and polydisperse polymers, allowing estimation of M̄r and diffusion coefficients. For sodium polystyrene sulfonates at substantially infinite dilution in 1.0 g L-1 Na2SO4, a linear relation has been observed between the logarithms of the molecular weight M̄n and the mean diffusion coefficient D in the M̄n range of 1000-90,000 g mol-1 or the D range of 30 × 10-7 to 2 × 10-7 cm2 s-1.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/app.1991.070420722