Preparation and Characterization of Porous Polyacrylonitrile Materials via Concentrated Emulsion Template Method

Abstract

INTRODUCTION Recently, highly porous polymer materials with controlled morphology prepared via concentrated emulsion template method had gained extensive research interests due to their favorable properties such as large surface area, high porosity, high absorbency capabilities and good permeability 1,2. The concentrated emulsions had been defined as emulsions in which the droplet phase occupies more than 74 % of the total emulsion volume. This figure represents the maximum volume ratio of uniform droplets packed in the most compact manner 2. Generally, concentrated emulsions consist of continuous phase, which contains monomers mixed with suitable crosslinker and surfactant and droplet phase, which comprises a solution of initiator and electrolyte in distilled water. After the polymerization of the continuous phase and the removal of the droplet phase, polymer foams with open-celled structures were produced. The polymer foams prepared via concentrated emulsion template method had been considered for many applications, such as filtration media, catalyst supports, tissue engineering scaffold and ion-exchange resins due to their unique properties 3,5. By far, the most widely investigated polymer foams prepared via concentrated emulsion template method were made of styrene and divinylbenzene as the continuous phase. Recently, more porous materials had been synthesized using other monomers, such as butyl acrylate, benzyl chloride and