C.Q. Zhao,W.G. Liu,Z.Y. Xu,J.G. Li,T.T. Huang,Y.J. Lu,H.G. Huang,J.X. Lin
Three kinds of methods based on extrusion and 3D printing and different acidic solutions (formic acid (FA), acetic acid (AA), glycolic acid (GA) and lactic acid (LA)) were applied for manufacturing the CS ducts. The tensile properties and preliminary cytotoxicity were measured for selecting the optimal ratio of CS slurry. The 3D printability of CS slurry was also studied. The tensile strength, Young’s modulus, and fracture strain were tested for evaluating the degree of mechanical matching to soft-tissue. The optimal solvent to CS was 30 wt.% GA solution. The CS slurry possessing shear-thinning properties was suitable for 3D printing. The tensile strength, Young’s modulus, and fracture strain of the CS rods were 10.98 ± 0.61 MPa, 12.38 ± 1.19 MPa, and 146.03 ± 15.05 %, correspondingly. The CS ducts manufactured by 3D printing had an excellent mechanical matching to soft-tissue, outstanding biocompatibility and have great potential for soft-tissue restorations.
A starch-based vitrimer was prepared by blending a crosslinkable macromolecular plasticizer with starch derivatives via extrusion. The crosslinkable macromolecular plasticizer improved the mechanical properties of the material by enhancing the entanglement of molecular chains. The plasticizing effect was remarkable, and the material could be machined and recycled by hot-pressing at 130 °C for 15 min. The properties of the starch-based vitrimer were basically maintained after processing. Exudation or migration of the plasticizer and retrogradation of the starch-based vitrimer were avoided by the presence of crosslinking bonds. The hydrophobicity of the material was suitably improved to prevent the influence of moisture in the environment on its performance.
In order to photocatalytic degradation of ethylene in environmental pollution, TiO 2 (B) featuring a multiphase crystal structure was first synthesized via hydrothermal synthesis method. The efficiency of photocatalytic degradation of ethylene and methyl orange by TiO 2 (B) was up to 49.23% and 60%, respectively, and the specific surface area of TiO 2 (B) was as large as 277.69 m 2 /g. Subsequently, photocatalytic films loaded with the TiO 2 (B) were produced using an extrusion casting machine coupled with a twin-screw extruder. The mechanical properties and barrier property to oxygen were enhanced by adding 1% TiO 2 (B) to photocatalytic films. The hydrophilicity of the photocatalytic films and the decrease in contact angle confirmed the existence of the ‘Honda-Fujishima effect’. The highest degradation efficiency of methyl orange and ethylene by the photocatalytic film could reach 9% and 7.79%, respectively. Both TiO 2 (B) and photocatalytic films showed good antibacterial properties against Escherichia coli and Staphylococcus aureus . TiO 2 (B) and photocatalytic films have been shown to have excellent photocatalytic degradation performance of organic compounds.
危险品化学品经营许可证（带存储）