| Abstract
| - We have studied the evolution in time of the structure factor of aggregating κ-carrageenanusing light scattering. Aggregation was induced by cooling solutions containing 0.01 M KCl below a criticaltemperature. The ionic strength of the solutions was fixed by adding 0.1 M NaCl. Large aggregates consistof locally rigid bundles formed by parallel aggregation of κ-carrageenan. The effect of concentration (C<0.3 g/L) and temperature on the structure was found to be small. The aggregation rate increases withincreasing concentration and decreasing temperature. The optical rotation, i.e., the helix content, is notinfluenced by aggregation. The molar mass, size, and interactions of nonaggregated κ-carrageenan weredetermined in the coil and the helix state. For the large molar sample used in this study (Mw = 4.2 × 105g/mol) the molar mass and the size are almost the same in the coil and the helix state.
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