Influence of titania on the morphological and mechanical properties of 1,3-butanediol dimethacrylate based polyHIPE composites

Macroporous polymer/TiO2 composites were synthesized by the polymerisation of 1,3-butanediol dimethacrylate (1,3-BDDMA) based water-in-oil high internal phase emulsions. High internal phase emulsions (HIPEs) having 80 vol% of internal phase were used as templates for inducing porosity in the resulting polymer composites. Apart from the monomer, either methyl methacrylate (MMA) or 2-ethylhexyl acrylate (EHA) was used as a co-monomer. In order to investigate the influence of nanoparticle loading on the morphological and mechanical properties of highly porous polymers, 1 to 10 wt% of colloidal TiO2 nanoparticles were introduced into emulsion templates. It was found that increasing the amount of nanoparticle loading from 1 wt% to 10 wt%, average cavity sizes decreased from 14.1 μm to 5.9 μm in the case of MMA co-monomer, and from 18.6 μm to 5.1 μm in the case of EHA co-monomer. Moreover, it was found that introducing 1 wt% of nanoparticle significantly improved the mechanical properties of both MMA and EHA copolymerized polyHIPEs. In order to explain the influence of nanoparticle loading and comonomer type on the physical properties appropriate regression analyses were conducted.