Glass beads surface modification

The surface properties of particles are very important with respect to their end use. Many particles are used for fillers and to impart properties that enhance a materials function. In order to do so, the particles need to be compatible with the environment into which they are placed. Often this is in a polymer matrix such as a film. To enhance particle compatibility of the surface of 2-5 pm silica particles and silica glass beads, surface modification of these particles was carried out. Surface modifications were accomplished by surface polymerization, surface polymer grafting, by surface dendrimerization and by developing organo-silicone particles. The surfaces obtained can have a wide variety of properties, fi om highly hydrophilic to highly hydrophobic, from anionic and cationic to nonionic, as well as being environmentally responsive. 

According to Potters Industries, A-glass is suggested for the majority of polymers with the exception of acetal and PTFE where E-glass should be used. The reason for surface modification of glass beads is explicitly illustrated in Figure 2.25. Coated spheres adhere to the matrix but uncoated spheres are easily delaminated from the matrix. Adhesion depends on the selection of coating for a particular matrix polymer. 

On the contrary, investigations, which dealt with the opposite intention, to utilize the hard structure and mechanical advantages of highly porous macroreticular resins (cross-linked to > 55% DVB), or even of glass beads for true solid phase peptide synthesis through surface reactions, proved to be of scientific interest only, but were unsuited for preparative peptide synthesis. Even modifications of the different types of solids by handle or... 

Liu, X. D., Tokura, S., Haruki, M., Nishi, N., and Sakairi, N. (2002). Surface modification of nonporous glass beads with chitosan and their adsorption property for transition metal ions. 

Surface Modification of Silica Particles and Silica Glass Beads... 

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