Study on the mechanism and performance of polymer gels by TE and PVA chemical cross‐linking

Conversion mechanism of thermal plasma-enhanced CH4-CO2 reforming system to syngas under the non-catalytic conditions

Thermal plasma activation of CH₄-CO₂ reforming (CRM) to syngas under non-catalytic conditions is an efficient and clean technology for the large-scale utilization of hydrocarbon resources and the conversion of greenhouse gases. This study investigates the equilibrium state and transformation mechanism of a CRM reaction system activated by thermal plasma through experimental, thermodynamic, and kinetic analyses. The experimental results illustrated that the CO₂ conversion rate and H₂ selectivity showed a downward trend with an increase in the CO₂/CH₄ molar ratio, whereas the CH₄ conversion rate and CO selectivity showed the opposite trend. When CO₂/CH₄ molar ratio was 6/4, the selectivity for CO and H₂ increased to 87.0 % and 80.8 %, respectively. Excess CO₂ promotes the partial oxidation of CH₄ to eliminate carbon deposition, resulting in an H₂/CO molar ratio value closer to 1. Thermodynamic results show that the thermal-plasma-initiated CRM reaction can reach thermodynamic equilibrium more easily than the conventional catalyzed reactions, achieving much higher feedstock gas conversion without carbon deposition. The kinetic results obtained from the PSR model revealed that CH₄ and CO₂ were cleaved to form free radicals at the instant of contact with the plasma flame. O, H, and other particles generated in the form of free radicals rapidly collided with each other and transformed into CO and H₂, accelerating the reaction process. The results presented in this study will help reveal the transformation mechanism of the CRM reaction activated by thermal plasma under non-catalytic conditions and provide a new perspective for studying CRM reactions.

Polymer Gels: Classification and Recent Developments in Biomedical Applications

Polymer gels are a valuable class of polymeric materials that have recently attracted significant interest due to the exceptional properties such as versatility, soft-structure, flexibility and stimuli-responsive, biodegradability, and biocompatibility. Based on their properties, polymer gels can be used in a wide range of applications: food industry, agriculture, biomedical, and biosensors. The utilization of polymer gels in different medical and industrial applications requires a better understanding of the formation process, the factors which affect the gel's stability, and the structure-rheological properties relationship. The present review aims to give an overview of the polymer gels, the classification of polymer gels' materials to highlight their important features, and the recent development in biomedical applications. Several perspectives on future advancement of polymer hydrogel are offered.