Journal of Materials Science, Vol.47, No.16, 6166-6178, 2012
Macroporous polyacrylates from terpene-acrylate thermoreversible photopolymerizable vehicle
Novel thermoreversible polymerizable vehicle was prepared from terpenes, such as camphene, camphor and menthol and acrylate monomers. The vehicle exhibits liquidity above room temperature and rigidity at room temperature, where the terpenes are crystalline dendrites and the acrylate monomer fills up the interdendritic space. The rigid vehicle polymerizes on UV illumination and the terpenes sublimed subsequently from the polymerized samples leaving highly porous polymeric samples with dendritic-shaped interconnected porosity up to similar to 92 vol%. Increasing the terpenes content, the thermoreversible component, results in coarser dendritic structures. Lower recrystallization temperatures produce finer dendritic network, whereas recrystallization close to terpenes melting point results in larger continuous macropores. The proposed advantages include fast manufacturing because of fast recrystallization, achieving large pore size up to 13 mu m and tailoring of the porosity through the portion of the sublimable vehicle and recrystallization temperature. The applicability of this novel technique in the biomedical field is demonstrated on a composition containing triethylene glycol dimethacrylate (TEGDMA), a monomer widely used for biomedical applications.