INTERPRETATION OF THE STRUCTURAL PARAMETERS DERIVED FROM THE ANALYSISOF POLYMER COLLOIDS BY SMALL-ANGLE X-RAY AND NEUTRON-SCATTERING

We reconsider the analysis of the structure of colloidal particles by small-angle scattering. Special emphasis is laid on the structural par ameters derived from a small-angle experiment conducted at different c ontrast. The forward scattering of the particles, their radius of gyra tion and the invariant are reconsidered in terms of a model introduced by Harrison (1969). Here the finite resolution of the experiment as w ell as the small size of the constituents of typical polymeric colloid s are taken into account by definition of a shape function phi (r) whi ch varies continuously between 0 and 1. Model calculations show that c areful measurements of the scattering intensity over a wide range of s cattering angles and contrasts may be used for a detailed analysis of the shape function.