Micelles Interparticle effects

A combination of these two effects is responsible for separation of the Li phase into micelle-rich and micelle-lean phases at the cloud point temperature. It is well known that entropic effects cause phase separation to occur in relatively dilute solutions of long, cylindrical particles, even in the absence of interparticle attraction. Hence phase separation is facilitated by micelle shape changes caused by higher values of v lal and, of course, also by a shift from a repulsive to an... 

A potential drawback of shell cross-linking is the need to perform such chemistries under relatively dilute conditions to avoid the occinrence of interparticle cross-linking. However it was recently demonstrated that SCK micelles could be successfully prepared at high solids with ABC triblock copolymers in which the C block forms the micelle core, the A block the outer coronal chains and the cross-linkable B block the inner coronal chains. Here, the outer A block is effectively acting as a steric barrier to inter-particle cross-linking (463,464). 

The positronium annihilation lifetime spectroscopy was successfiilly applied to the study of pore structure of the as-synthesized sample of MCM-41. The PALS technique can supply information about imperfections in the template structure as well as silica walls of MCM-41. The interior of cylindrical micelles encaged in the silica skeleton exhibits the presence of some kind of defects which disappear when pressure of argon increases. Howeva-, small voids present in the walls of silica network are resistant to compression and their dimensions are independent of pressure. Under mechanical pressure one can observe total destruction of interparticle pores at about 140 MPa. However, small voids in the sample are present up to 450 MPa. Temperature treatment leads to quite different effects than those observed for pressure experiment. 

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