Cohesive‐energy‐densities of high polymers. Part. III. Estimation of C. E. D. by viscosity measurements

From the Indian Institute of Technology, Kharagpur, India
Die Makromolekulare Chemie 03/2003; 67(1):75 - 83. DOI: 10.1002/macp.1963.020670107

ABSTRACT The intrinsic viscosities and the slopes of ηsp/C against C were estimated for natural rubber, polystyrene, and polyisobutene in hydrocarbon and high mol.wt. alkyl ester solvents. Whereas no correlation could be established between slopes and c.e.d. (cohesive energy-densities) balance of the systems, the plot of [η] versus δ, the solubility parameters of the solvents, yielded smooth curves similar to those obtained by plotting swelling coefficients against δ. GEE's method of estimating δp from swelling coefficients, was therefore extended to estimate δp from viscosity measurements. The present values of δp are in good agreement with those obtained by swelling measurements.Die STAUDINGER-Indices (Intrinsic-Viskositten) und die Neigungen der Kurven der Funktion ηsp/c = f(c) von natürlichem Kautschuk, Polystyrol und Polyisobutylen in Kohlenwasserstoffen und höhermolekularen Alkylestern als Lösungsmittel wurden bestimmt. Falls keine Beziehung zwischen den Neigungen und dem Kohsionsenergiedichte-Gleichgewicht der Systeme gefunden wurde, gab die Auftragung von [η] gegen δ, den Löslichkeitsparametern der Lösungsmittel, glatte Kurven. Diese sind hnlich jenen, die man beim Auftragen der Quellungskoeffizienten gegen δ erhlt. Deshalb wurde GEEs Methode der Bestimmung von δp aus den Quellungskoeffizienten zur Bestimmung von δp aus Viskosittsmessungen erweitert. Die gefundenen Werte von δp stimmen gut mit jenen aus Quellungsmessungen erhaltenen überein.

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