Synthesis, Characterization, and Gas Adsorption Performance of Amine-Functionalized Styrene-Based Porous Polymers

In recent years, porous materials have been extensively studied by the scientific community owing to their excellent properties and potential use in many different areas, such as gas separation and adsorption. Hyper-crosslinked porous polymers (HCLPs) have gained attention because of their high surface area and porosity, low density, high chemical and thermal stability, and excellent adsorption capabilities in comparison to other porous materials. Herein, we report the synthesis, characterization, and gas (particularly CO₂) adsorption performance of a series of novel styrene-based HCLPs. The materials were prepared in two steps. The first step involved radical copolymerization of divinylbenzene (DVB) and 4-vinylbenzyl chloride (VBC), a non-porous gel-type polymer, which was then modified by hyper-crosslinking, generating micropores with a high surface area of more than 700 m² g^-1. In the following step, the polymer was impregnated with various polyamines that reacted with residual alkyl chloride groups on the pore walls. This impregnation substantially improved the CO₂/N₂ and CO₂/CH₄ adsorption selectivity.

Graphene oxide/silver nanohybrid: Optimization, antibacterial activity and its impregnation on bacterial cellulose as a potential wound dressing based on GO-Ag nanocomposite-coated BC

Recently, bacterial cellulose (BC) based wound dressing have raised significant interests in medical fields. However, to our best knowledge, it is apparent that the BC itself has no antibacterial activity. In this study, we optimized graphene oxide-silver (GO-Ag) nanohybrid synthesis using Response Surface Methodology and impregnate it to BC and carefully investigate their antibacterial activities against both the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Staphylococcus aureus. We discover that, compared to silver nanoparticles, GO-Ag nanohybrid with an optimal GO suspension's pH and [ G O ] [ A g N O 3 ] ratio is much more effective and shows synergistically enhanced, strong antibacterial activities at rather low dose. The GO-Ag nanohybrid is more toxic to E. coli than that to S. aureus. The antibacterial and mechanical properties of BC/GO-Ag composite are further investigated.

Surface Modification of PDMS and Plastics with Zwitterionic Polymers

Surface modification of PDMS, polycarbonate, and acrylic resin was examined using various methacryl polymers bearing sulfobetaine, phosphoryl choline, and oligoethylene glycol units. We have found that zwitterionic polymers are adsorbed on the PDMS surface treated with plasma. The surface of PDMS is stable to keep high hydrophilicity after a month of the modification. On the other hand, one of sulfobetaine polymers showed distinguished adsorption behavior in the case of polycarbonate surface treated with plasma. Suppression effect for nonspecific adsorption of BSA was evaluated using polycarbonate and acrylic resin modified with the polymers. The modified surfaces showed suppression effect for nonspecific adsorption of BSA compared with the surface only treated with plasma.