HIPE, cell size

It is worthwhile to note the relatively large cells (up to 10-20 pm in diameter) and the large number of about 1 pm windows between adjacent cells. The large pore volume results directly from the large internal volume of water incorporated in the HIPEs (more than 95%). The large average cell size corresponds roughly to the size of the water droplets in the HIPEs. 

The HIPE foams are cirrrently of interest because of their low density, microstructirral and open cell, and high absorbency. A number of HIPE foams applications were reported, including, polymeric membranes, ion exchange resin [4, 6] and absorbents. The authors are currently investigating the soimd absorption characteristics of these foams. The success in these applications is highly dependent on the microcellitlar structure and morphology, manifested in, cell size, cell density, open cell content and volume expansion ratio. 

Consequently, open microcellular foams modified by introducing viscosity improvers into conventional water and styrene systems were prepared using the HIPE polymerization techitique. Investigation of the microstractural morphology of polymerized foams led to a conclusion that average cell size decreases as viscosity improver concentration and surfactant and cross linking agent increases. Relation between open cell content and volume expansion ratio as a function of the PB, DVB and SMO contents was attempt, the correlation was quite satisfactoiy. 

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