000			01787nam a2200205Ia 4500
008			220216s9999 xx 000 0 und d
100			_aOkieimen F E
245		0	_aEstimation of dilute solution viscosity parameters of rubber seed oil alkyds
260			_bJournal of Applied Polymer Science _c1998
300			_a1987-1992
520			_aViscosity measurements were carried out in methyl ethyl ketone (MEK) and dimethyl formamide (DMF) for rubber seed oil alkyds having oil content of 20(I), 30(II), 35(III), 40(IV), 50(V), and 60;(VI). Viscosity molecular weights, intrinsic viscosities, and viscosity parameters K and a, characteristic for both polymrsa and solvents, were determined. Generally, solubility properties were found to depend on molecular weight and polarity of the alkyds and solvent. Intrinsic viscosities of the alkyds were larger in DMG than in MEK, suggesting DMF to be a better solvent than MEK for rubber seed oil alkyds. Molecular weights determined for the alkyds range from 441 for sample III to 1323 for sample V. The viscosity molecular weights are in the reasonable agreement with the values determined for samples II-V in MEK and samples I-IV in DMF. The values of Huggins constant for these alkyds were also determined. Data reported also suggest that rubber seed oil alkyds tend to tolerate relatively basic solvent, such as DMF. Fractionation of the alkyds was considered to be in respect of molecular weight and polarity of the alkyds, and results show that low-molecular weight species constitute greater proportion of the alkyds.
650			_aAlkyds
650			_aFractionation
650			_aMolecular weight
650			_aRubber seed oil
650			_aSolubility parameters
650			_aViscosity
700			_aAigbodion A I
942			_cJS
999			_c58824 _d58824