ISSN:
1436-2449
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Summary In situ fluorescence and light scattering techniques were used to study the formation of heterogeneities during the free-radical crosslinking polymerization of sodium acrylate (NaAc) in the presence of N,N'-methylene(bisacrylamide) (BAAm) as a crosslinker. Pyranine was used as a fluorescence probe in the experiments. The reactions were carried out at room temperature and at a monomer concentration of 20.6 w/v% in water. It was found that the gel forming system became turbid at the start of the reaction; continuing polymerization and crosslinking reactions turned the opaque gels into slightly opaque and finally transparent gels. Two peaks were observed both in the scattered and emitted light intensities versus the reaction time plots. The first peak corresponds to the formation and growth of the phase separated domains whereas the second peak reflects the macrogelation point in the reaction system.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002890050631
