Driving Forces Responsible for the Blackberry Formation

IDENTIFICATION OF THE DRIVING FORCES RESPONSIBLE FOR THE BLACKBERRY FORMATION 

The driving forces of the blackberry self-assembly process are unique and differ from many types of traditional systems that have been well studied. Unlike surfactant micelles and vesicles, hydrophobic interactions do not contribute to the blackberry formation because the POMs have no hydro-phobic moieties. In colloidal systems, self-assembly occurs by van der Waals forces. As previously mentioned, van der Waals forces do not contribute significantly to POM self-assembly. 

The role of the counterions is important to the POM self-assembly proeess if hydrophobic interactions and van der Waals forces do not drive the blackberry formation. Past studies have shown that the counterions are effective in the self-assembly process with some contribution from hydrogen bonding. The counterions associated with the large POM macroions are most likely shared between neighboring macroions. In this manner, the like-charged POM macroions, which are expected to repel one another, actually exist close to other POMs. Thus the observation is that there exists an attraction among the like-charged POM macroions. To determine how counterions contribute to blackberry formation, studies were performed to determine the effect of cationic valent state and hydrated size on the blackberry formation, which is described later. 

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It is important to determine the driving forces responsible for the blackberry formation in dilute solutions. Because the POMs do not have any hydrophobic regions, hydrophobic interaction can be excluded. We first examine... 

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