𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Flexibilität und hydrodynamische eigenschaften von polymethylmethacrylat in binären mischlösungsmitteln

✍ Scribed by Wunderlich, Winfried

Publisher
Wiley (John Wiley & Sons)
Year
1981
Weight
533 KB
Volume
182
Category
Article
ISSN
0025-116X

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Light scattering and viscosity measurements of poly(methyl methacrylate) have been carried out, in order to investigate the correlation of unperturbed dimensions and intrinsic viscosity of the polymer relative to the thermodynamic properties of solvent mixtures as compared to results obtained in single component solvents. The unperturbed dimensions of the polymer turned out to be unaffected by the mixed solvent, whereas a strong dependence of the hydrodynamic radius on the enthalpy of mixing of the two solvent components was observed. Hence unequivocal conclusions about the chain structure of the dissolved polymer cannot be drawn from hydrodynamic measurements in mixed solvents. If values of the viscosity constant K~0~ in these systems in the vicinity of the Θ‐point are extrapolated according to the Burchard‐Stockmayer‐Fixman equation, they do not agree with data measured at T = Θ.

📜 SIMILAR VOLUMES

Äthylcellulose in lösung. Hydrodynamisch
Äthylcellulose in lösung. Hydrodynamische eigenschaften und ungestörte dimensionen
✍ Meyerhoff, Von G. ;Sütterlin, N. 📂 Article 📅 1965 🏛 Wiley (John Wiley & Sons) ⚖ 473 KB

An fiinf hhylcellulosefraktionen wurden Viskositats-und Reibungsuntersuchungen ausgefiihrt. Die Molekulargewichte wurden aus den Sedimentations-und Diffusionskoeffizienten bestimmt. Ein eigenes Verfahren erlaubt es, aus den Konstanten K, und a der Viskositgts-Molekulargewichtsbeziehung die ungestort