From polysaccharides to UV-curable biorenewable organo/hydrogels for methylene blue removal

Biorenewable “all-starch”-derived organo/hydrogels (OHGs) were prepared via “green” and fast UV-curing and tested as bio-adsorbents for the removal of methylene blue from water. Methacrylated starch (MS) and acrylated starch derivative, γ-cyclodextrin (ACy), were synthetized for use as OHG precursors for the photopolymerization process. Real-time photorheology confirmed the high reactivity of the prepared photocurable precursors. The mechanical properties and swelling behaviour of the photocured OHGs were examined focusing on the influence of the increasing amount of ACy. The MS-ACy OHGs were tested as innovative and environmental-friendly biorenewable materials for water treatment, using methylene blue (MB) as reference pollutant. The experimental data reveal that OHGs containing an increasing amount of ACy show not only superior mechanical strength but also sorption properties as a consequence of the high crosslinking efficiency of the acrylated cyclodextrin derivative and its ability to form host-guest inclusion complexes. Finally, the printability of these photocurable formulations via digital light processing (DLP) 3D – Printing is confirmed, envisaging the fabrication of absorbing materials with complex and application-tailored geometry, which could represent a new frontier for wastewater treatment.