Title of article :
Dynamic light scattering studies on random cross-linking of polystyrene in semi-dilute solution
Author/Authors :
Liu، نويسنده , , Ruigang and Gao، نويسنده , , Xia and Oppermann، نويسنده , , Wilhelm، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2006
Pages :
7
From page :
8488
To page :
8494
Abstract :
The random cross-linking of appropriately functionalized polystyrene in semi-dilute toluene solution (c = 0.01–0.05 g/mL) was studied by time-dependent measurements of dynamic light scattering. Macroscopic gelation occurred from concentrations as low as 0.02 g/mL. The gelation time, determined from the first appearance of fluctuations of the scattering intensity and the initial amplitude of the intensity correlation function (ICF), decreases markedly from about 100 min to 10 min with an increase of polymer concentration or cross-linker content. After the gel point, the ICFs display a characteristic power-law decay. The power-law exponent, n = 0.75 ± 0.06, does not change with (i) extent of reaction, (ii) polymer concentration, and (iii) cross-linker concentration, within the inspected ranges. This universal behavior is traced back to the fact that gelation took place as a result of random cross-linking of existent macromolecules, whose state of solution does not change markedly during conversion.
Keywords :
polystyrene , gelation , dynamic light scattering
Journal title :
Polymer
Serial Year :
2006
Journal title :
Polymer
Record number :
1727923
Link To Document :
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