Bicontinuous highly cross-linked poly(acrylamide-co-ethyleneglycol dimethacrylate) porous materials synthesized within high internal phase emulsions

Abstract

PolyHIPEs are highly porous, cross-linked polymers typically synthesized within high internal phase emulsions (HIPEs). This work describes the synthesis of novel acrylamide (AAm) based polyHIPEs cross-linked with ethyleneglycol dimethacrylate (EGDMA). In this methodology, the AAm and EGDMA monomers were taken in HIPE external and internal phases, respectively. The subsequent polymerization led to the formation of bicontinuous polyHIPEs. The immiscibility of AAm in the aqueous phase with EGDMA monomer was overcome by this methodology. The EGDMA concentration in the polyHIPEs was varied between 30 and 70% by weight to get polymers with various degrees of cross-linking. Dimensionally stable polyHIPEs with a high degree of cross-linking were obtained. Porous polymers with open-cellular architecture resulted with interconnecting pores in polyHIPEs. Water absorption of polyHIPEs was found to be inversely proportional to the EGDMA concentration. The hydrophilicity and porous structure of the resultant polyHIPEs were found to depend on the EGDMA concentration.