lOO FUNDAMENTALS OF SUBMI C RO SC OPI C MORPHOLOGY I 



Intermicellar spaces. The regions between the meshes of the micellar 

 framework may represent a homogeneous phase if they are filled with 

 a uniform liquid or gas. This only holds good so long as the gel frame 

 consists of strands which can themselves be considered as a phase, so 

 that a phase boundary exists. If the strands become so thin, however, 

 as to reach the dimensions of a chain with the thickness of a single 

 molecule, the concept phase loses its significance. 



(ni) (002) (022) (113) (222) 



Fig. 69. X-ray diffraction pattern of a) ramie and h) %\W stained with gold. In addition to 

 the fibre diagram, Debye-Scherrer rings of gold (m), (002) etc. are seen (from Frey- 



Wyssling, 1937a). 



Information as to the dimensions of the intermicellar spaces in the 

 gel frame can be obtained in various ways. If one succeeds in filtering 

 particles of known size through a gel, the inference is that the pores 

 are bigger than the particles, as in an ultrafilter. Unfortunately, how- 

 ever, it is not possible to obtain absolute values of the pore size of the 

 intermicellar spaces with the aid of ultrafiltration (Czaja, 1950), since 

 differences in electric charge or in chemical behaviour (hydrophoby) 

 very strongly influence the ease with which filtration of the particles 

 takes place (Morton, 1935). For this reason, only relative sizes can be 

 obtained, which cannot be compared with the absolute values deter- 

 mined by means of X-rays. 



Until now it has not been possible to obtain X-ray diagrams of the 

 intermicellar substances ; for, even when in the solid state, they do not 

 usually show the properties of crystals. In the plant cell wall, e g.. 



