- Communications Faculty of Sciences University Ankara Series B Chemistry and Chemical Engineering
- Vol: 35
- Determination of the Molecular Weight of Linear Polymers From Viscosity Measurements Carried out in ...
Determination of the Molecular Weight of Linear Polymers From Viscosity Measurements Carried out in the Solvent Mixtures
Authors : E. Pulat
Pages : 0-0
Doi:10.1501/Commub_0000000339
View : 14 | Download : 5
Publication Date : 1989-01-01
Article Type : Research
Abstract :In this work polyvinyl acetate prepared by B. D. H Laboratory »Chemicals Di- vision has been used. The intirinsic viscosities have been determined in acetone-benzene mixtures of various percentâges. By using these intrinsic viscosity values the viscosity average molecular weights of the same polyvinyl acetate sample have been calculated from this relationship: [?]] = K' M»' (1) In this equation the values of K and a' are calculated from the following equations: K' = — Ki (1—fi)3 + K2 (1—fi)3 (2) a' = «ı fi + a2 ( 1—fı) (3) Where fi stands for the volüme fraction of one solvent in the solution. Kn aı and K2, a2 are constants for a given polymer-solvent system and temperature. The values of Kn aı and K2, a2 are given in the literatures [1, 2 ] for polyvinyl ace- tate-benzene and polyvinyl acetate-acetone systems. The values of the molecular weight abtained by this method are satisfactorily good within experimental errors. The benzene-acetone mixture is better than püre ben¬zene and acetone as solvent for the polyvinyl acetate. Especially the solution containing 20-40 % benzene is the most effective solvent for this polymer. Here polar and nonpolar parts of the polymer are respectively affected by acetone and benzene.Keywords : Determination, Molecular, Linear