Apparent density of hypercrosslinked polystyrenes

Similar to the gel-type styrene copolymers, the hypercrosslinked networks based on both linear polystyrene and styrene-DVB copolymers are transparent materials, being in dry or swollen state. Nevertheless, alternatively to the conventional copolymers, the hypercrosslinked networks exhibit very low apparent density (Papp) when isolated from the reaction media and dried. The apparent density of the polymers (I) based on linear polystyrene (Table 7.7) decreases with increasing the degree of crosslinking  

Wp (cm /g) is the total pore volume calculated from the true (1.12 cm /g) and apparent densities, (cm /g) is the total pore volume determined by mercury intrusion. 

Reprinted from [175] with kind permission of Elsevier. 

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