Scattered light intensity in the strongly opalescent region for the system polystyrene-diethyl malonate

The angular distribution of scattered light intensity and the turbidity for the system polystyrene ($M_w=2.0\mathrm{}\times {10}^5$, $\frac{M_w}{M_n}<1.02\mathrm{}$)-diethyl malonate were measured along the critical isochore. The effect of multiple scattering was found to be minimized in the forward direction even close to the critical temperature. We obtained the critical exponent $\gamma =1.23\mathrm{}\pm 0.03$ for the osmotic compressibility through turbidity measurements.