Novel antibacterial properties of composites prepared from thermally treated waste white scallop shell powder (TWWSSP) and modified polylactide (MPLA) are reported. The waste shell (calcium carbonate, CaCO 3 ) was calcined at 1000 °C to completely form calcium oxide (CaO) and calcium hydroxide (Ca(OH) 2 ). The composition and structure of the calcined product were characterized using energy dispersive spectrometry, Fourier transform infrared spectroscopy, and X-ray diffraction. The TWWSSP was studied to determine its effectiveness as a bactericidal agent when incorporated into MPLA to form composites. Infrared, tensile, and morphological characterizations indicated an enhanced adhesion between the TWWSSP and the MPLA in the composites and an improved compatibility compared with the PLA/WWSSP composites. The MTT assay and cell adhesion tests on the composites revealed that the relative growth rate of Mus dunni fibroblast (MDFB) cells increased with an increasing TWWSSP content, which indicated that the composites were not cytotoxic. Moreover, TWWSSP containing CaO and Ca(OH) 2 enhanced the antibacterial activity of the composites; MPLA composites that contained TWWSSP had a better antibacterial activity. The antibacterial and biodegradable properties of the MPLA/TWWSSP and PLA/WWSSP composites have a great potential for many applications, especially food packaging and biomedical materials.

Concurrent advances in the programmable synthesis of nanostructured materials and additive threedimensional (3D) manufacturing have created a rich and exciting opportunity space to fabricate novel materials and devices. In particular, creating complex hierarchical device geometries from mesoporous materials presents several scientifically interesting and technologically relevant challenges. Here, we show how digital light processing of photoresponsive building block defined by an oxozirconium methacrylate cluster with 12 methacrylic acid ligands can be used to enable the creation of complex superstructures characterized by multilevel porous networks. Inspired by similarly complex 3D hierarchical mesoporous structures ubiquitous in nature, we demonstrated the fabrication of a 3D leaf as a proof of concept. This work demonstrates how exciting opportunity space emerging at the intersection of inorganic building blocks, mesoporous materials, and 3D digital light processing opens new pathways to create functional hierarchical superstructures and devices with complex geometries.

A biodegradable composite nanofiber containing polyhydroxyalkanoate (PHA) or modified PHA (MPHA) and treated fish-scale powder (TFSP) was prepared and characterized. The powder (20–80 nm) was prepared by grinding after treating FSP with water, acid, and heat (450 °C) to yield the TFSP. Composite nanofibers (100–500 nm long) of TFSP/PHA and TFSP/MPHA were fabricated by electrospinning using a biaxial feed method. The TFSP, which had a high hydroxyapatite content, was suitable as a filler for composites. The Ca/P ratio of the TFSP was similar to that of the human bone. Particle size analysis and analysis of scanning electron microscopy images indicated that, compared with the PHA/TFSP composite, the MPHA/TFSP nanofibers were more uniform and bonded more strongly in the matrix. The tensile strength at failure of the MPHA/TFSP specimens was enhanced and increased with increasing TFSP content. The elongation at failure was lower and decreased with increasing TFSP concentration. The water contact angle decreased with increasing TFSP content in PHA/TFSP and MPHA/TFSP nanofiber membranes. The TFSP enhanced the hydrophilic effect of the PHA/TFSP and MPHA/TFSP nanofiber membranes and provided a more suitable environment for cell growth. This composite nanofiber has potential in many biomedical applications.

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The development of green and renewable materials has attracted increasing attention in recent years. Hence, biocomposite-based packaging materials have been investigated to replace petrochemical materials in several industries, such as the food packaging and electronics packaging industries. The tensile and thermal properties of biocomposite-based packaging materials composed of polylactic acid and plant fiber were mainly investigated in the current literature, but fewer studies on the improvement of water resistance and water vapor/oxygen barrier properties of composite materials were performed. Herein, we describe a composite film comprising TBFP [a mixture of bamboo fiber powder (BFP) and silica aerogel powder] that was combined with modified polylactic acid (MPLA) in a melt-mixing process. The structure, morphology, tensile strength, thermal properties, water absorption properties, water vapor/oxygen barrier effect, cytocompatibility, and biodegradability of the composites were characterized. MPLA and TBFP improved the properties of these composites. Fourier transform infrared and X-ray diffraction spectra have shown interfacial adhesion of MPLA/TBFP, resulting in a tighter structure. Hence, the MPLA/TBFP composite had higher elongation at failure (ε), tensile strength at failure (δ), Young’s modulus (E), initial decomposition temperature at 5 wt % loss (T 5%), residual yields, oxygen transmission rate, contact angles, lower thermal conductivity (k) values, water vapor transmission rate, and water absorption and biodegradability compared with PLA and PLA/BFP. It indicates that the MPLA/TBFP composites exhibited more favorable tensile strength, water resistance, and water vapor/oxygen barrier than the PLA and PLA/BFP composites. Cell growth analysis showed that the MPLA/TBFP and PLA/BFP composites own good cytocompatibility. Moreover, the biodegradability of the PLA/BFP and MPLA/TBFP composites increased with the filler (BFP or TBFP) concentration. Because of these improvements in their properties, composites can be used as packing materials in many perspectives.