Production of polystyrene spheres for use as a templating material for polyaniline monolith structures.

摘要

Polystyrene (PS) spheres are potentially useful as a reproducible, sacrificial templating material for monolith columns once they can be utilised to create a uniform microstructured packing which enables a higher monolith batch to batch reproducibility. To achieve PS spheres which can meet these requirements, their synthesis was optimised. Parameters investigated included variation of reactant concentrations, along with optimisation of reaction conditions temperature, agitation speed and nitrogen flow during aeration. Temperature and agitati on played vital roles in the size and homogeneity of the synthesised PS spheres. Temperature affected the equilibrium concentration of monomer in the aqueous phase. When reaction temperature was increased, sphere size reduced and as reaction temperature decreased sphere size increased. A similar trend was seen when agitation speed was varied. At higher agitation speed average PS sphere size decreased as the rate of polymerisation increased. At lower agitation speed the average PS sphere size increased as the rate of polymerisation decreased. Ensuring fluctuations in both temperature and agitation were kept to a minimum was key to maintaining reproducibility. Any fluctuation above ~10% in either temperature or agitation speed affected standard deviation irreversibly. The facile dissolution of the PS spheres was also investigated. If the spheres produced could not be dissolved, their use as a sacrificial templating material would not be possible. By decreasing the original concentration of cross-linker, dissolution increased dramatically