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Molecules of the amphiphilic polyalcohol [9]-10-[9] arborol (molar mass M = 1053 g mol -1 dissolved in water form gels which are thermo-reversible and shear sensitive. The gel formation sets in above a characteristic composition y gel of the solution and temperature T gel (y gel = 7.5.10 -3 ; T gel 35 °C ; y, mass fraction of the arborol). T gel increases (slowly) with increasing values of y > y gel (T gel (y=0.02) 47 °C). The stiffness of the gels increases with increasing values of y and increasing values of the temperature difference (T gel -T). The states of the solutions (of the gels) at temperatures near T gel and compositions near y gel are studied by static and dynamic light scattering experiments. The dynamics of the structure of dilute arborol gels at constant temperature allows to obtain the normalized ensemble averaged correlation function g (2) (q, τ) of the light scattered by the gels by accumulating the corresponding time averaged correlation function g (2) time (q, τ) over long times t up to 150 h (q, scattering vector ; τ, correlation time). The kinetics of the aggregation and the gel formation after a temperature jump from an initial thermodynamic equilibrium state at temperature T i (> T gel ) to a final temperature T f (< T gel ) is monitored by static light scattering experiments. The change of the scattered intensity I s (θ = 90°) (θ, scattering angle) at T f with time t shows two regimes : an aggregation regime (t< |
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