Relationships between the viscosity, molecualr weight and concentrtion of acacia polyacantha and fractions at 298K

الملخص EN

Acacia Polyacantha gum has been lRK'"‘,na,c'i u s jn g éthanol and acetone as fractionated solvent; four different fractions were obtained and labeled PO-F1E - PO-F4E and PO-F1A - PO-F4A in éthanol and acetone respectively.

Viscometric measurements, in 0.1 M sodium chloride solution at 25°C, were performed with Acacia Polyacantha and fractions.

Two methods are used (single point détermination and graphical extrapolation) to détermine the values of intrinsic viscosity and viscosity-average molecular weight.

The value of intrinsic viscosity and viscosity-average molecular weight were compared in order to verify the suitability of the single point to détermine the viscosity of Acacia Polyacantha and fractions.

Molecular weight of the Acacia Polyacantha and fractions were also Relationships between the Viscosity, Molecualr Weigh t and Concentration of Acacia By: A.

O sman M.

E.

O sman S.

G.

D.

Alharthi A.

Y.

Al Amin * determ ined by apply M ark -Ilouwink-Sa knrad a équation using the values o f intrinsic viscosity obtaine d by single point déte rmination and grap hica l extrapolation équations.

The parameters identified by the Mark-Houwink équation arc In] = 1.71 x 10-2M0.0 4 for Acacia Polyacantha sam plcs, |q| = 3.46 M0.29 for éthanol fractions and [q] = 9.8 M0.02 for Acctone fractions of Acacia Polyacantha.

The molecular weight results obtained by membrane osmometry were compared with that obtained by GPC-MALLS.