Synthesis of PolyHIPEs from Photocurable Water-in-Oil High Internal Phase Emulsions by Using a Sustainable Monomer: β-Myrcene

Recently, there has been an increasing interest in the synthesis of bio-derived and sustainable polymers due to limited petroleum resources and the dependence of polymer chemistry on fossil fuels. Terpenes which are found in nature in wide variety of structures, are a large family derived from plants. Isoprene like structure of terpenes make these natural compounds susceptible to polymerization. In this work, β-myrcene, which is an acyclic monoterpene was used in the synthesis of photocurable porous polymer monoliths via high internal phase emulsion (HIPE) templating. Photocuring of β-myrcene in HIPE templates has been achieved by the free radical copolymerization crosslinking reaction with 1,4-butanediol dimethacrylate (1,4-BDDMA). To determine the effect of monomer ratio on the crosslink density and pore morphology of the resulting polyHIPEs, the volume ratio of β-myrcene in the external phase has been varied from 10 to 90. Crosslink density of the polyHIPEs has been calculated by swelling experiments using Flory-Rehner Theory. In the end, polyHIPEs exhibiting pore morphology constituted of cavities and interconnected pores has been obtained in all cases. However, it has been determined that 60% is the optimum β-myrcene ratio to obtain a highly crosslinked polyHIPE accompanied with an open-cellular pore morphology.