Electrostatic agglomerated substrates

The second stationary phase architecture (electrostatic agglomerated films on nonporous substrates, EANPS) was one of the first types of... 

Electrostatic Agglomerated Ultra-Wide-pore Substrates... 

Structure EANPS = electrostatic agglomerated nonporous substrate, EAWPS = electrostatic agglomerated wide-pore substrate, PGPS = polymer grafted porous substrate, SMPSS = silane modified porous silica substrate, CMS = chemically modified substrate, APCS = adsorbed polymer coated substrate. 

When the KCl(lOO) substrates are held at RT we can observe that the microcrystals are equally distributed in perpendicular directions. In addition to the increase in size with increasing Tgub, the microcrystals in the same direction tend to agglomerate leaving, however, the hnal microcrystal distribution unaltered no temperature-induced in-plane preferential orientation is observed. In case 3 a considerable number of microcrystals become curved. This is due to the triggering of in-plane growth directions other than the equivalent [110] directions caused by the contributions of the electrostatic and van der Waals interactions to the total energy at the interface (Caro et al, 1997). 

Latex-based anion exchangers are comprised of a surface-sulfonated polystyrene/divi-nylbenzene substrate with particle diameters between 5 pm and 25 pm and fully animated porous polymer beads of high capacity, which are called latex particles. The latter have a much smaller diameter (about 0.1 pm) and are agglomerated to the surface by both electrostatic and van-der-Waals interactions. A scanning electron micrograph of this material is shown in Fig. 3-12. Hence, the stationary phase features three chemically distinct regions ... 

Latex cation exchangers were introduced by Dionex Corp. 10 years later than latex-agglomerated anion exchangers. These types of cation exchangers consist of a weakly sulfonated PS-DVB substrate with latex beads with a very small diameter agglomerated on its surface by both electrostatic and van der Waals interactions. 

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