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Poly(lactic acid)/poly(trimethylene carbonate) (PLA/PTMC) films incorporated with cinnamaldehyde (0, 3, 6, 9, and 12 wt%) were prepared by solvent casting and characterized by physical, mechanical, and antimicrobial properties. SEM analysis revealed that the surface of film became rougher with certain porosity when cinnamaldehyde was incorporated into the PLA/PTMC blends. Cinnamaldehyde acted as plasticizers which reduce the intermolecular forces of polymer chains, thus improving the flexibility and extensibility of the films. Differential scanning calorimetry showed that the crystallinity of PLA phase decreased by the presence of cinnamaldehyde in the composite films. Water vapor permeability of films increased with the increase of cinnamaldehyde loading. However, the active PLA/PTMC/cinnamaldehyde composite films showed adequate barrier properties for food packaging application. Incorporation of cinnamaldehyde to the PLA/PTMC polymer matrix improved the antimicrobial activity of active packaging films. These results indicated that the best compromise between mechanical, barrier, thermal, and antimicrobial properties could be achieved by the addition of 9 wt% cinnamaldehyde into PLA/PTMC blends.

Graphene aerogel (GA) possessing good electrical conductivity and low weight has been widely considered as a promising candidate for high-performance microwave-absorbing (MA) materials. However, simultaneous realization of high reflection loss (RL), low thickness, and light weight remains very challenging for GA because of the trade-off between impedance match and attenuation ability. Herein, through use of (3-aminopropyl)­triethoxysilane as a surface modifier and cross-linker, the GA materials with precisely controlled density are fabricated via a unique solvothermal protocol of zero-volume shrinkage. The density-controlled GA (4.5 mg·cm–3) exhibits a remarkable minimum RL (RLmin) of −50 dB at a thickness of 1.14 mm in the K-band, owing to the optimized dielectric properties. Moreover, even higher attenuation ability without sacrificed impedance match is obtained by incorporating magnetic Fe3O4@C microspheres into the density-controlled GA. Superior MA performance involving unprecedented RLmin of −54.0 dB and qualified bandwidth covering 80% of the K-band has been achieved in the superlight Fe3O4@C/GA composite at a thickness less than 1 mm, which is highly desirable for MA material applied in mobile devices.

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Globally, millions of people die of microbial infection-related diseases every year. The more terrible situation is that due to the overuse of antibiotics, especially in developing countries, people are struggling to fight with the bacteria variation. The emergence of super-bacteria will be an intractable environmental and health hazard in the future unless novel bactericidal weapons are mounted. Consequently, it is critical to develop viable antibacterial approaches to sustain the prosperous development of human society. Recent researches indicate that transition metal sulfides (TMSs) represent prominent bactericidal application potential owing to the meritorious antibacterial performance, acceptable biocompatibility, high solar energy utilization efficiency, and excellent photo-to-thermal conversion characteristics, and thus, a comprehensive review on the recent advances in this area would be beneficial for the future development. In this review article, we start with the antibacterial mechanisms of TMSs to provide a preliminary understanding. Thereafter, the state-of-the-art research progresses on the strategies for TMSs materials engineering so as to promote their antibacterial properties are systematically surveyed and summarized, followed by a summary of the practical application scenarios of TMSs-based antibacterial platforms. Finally, based on the thorough survey and analysis, we emphasize the challenges and future development trends in this area.