In the present study, silver (Ag) nanoparticles and maleic anhydride-grafted polyolefin elastomer (MAH-g-POE) were used as enhancement additives to improve the performance of the polyoxymethylene (POM) homopolymer. Specifically, the POM/Ag/MAH-g-POE ternary nanocomposites with varying Ag nanoparticles and MAH-g-POE contents were prepared by a melt mixing method. The effects of the additives on the microstructure, thermal stability, crystallization behavior, mechanical properties, and dynamic mechanical thermal properties of the ternary nanocomposites were studied. It was found that the MAH-g-POE played a role in the bridging of the Ag nanoparticles and POM matrix and improved the interfacial adhesion between the Ag nanoparticles and POM matrix, owing to the good compatibility between Ag/MAH-g-POE and the POM matrix. Moreover, it was found that the combined addition of Ag nanoparticles and MAH-g-POE significantly enhanced the thermal stability, crystallization properties, and mechanical properties of the POM/Ag/MAH-g-POE ternary nanocomposites. When the Ag/MAH-g-POE content was 1 wt.%, the tensile strength reached the maximum value of 54.78 MPa. In addition, when the Ag/MAH-g-POE content increased to 15wt.%, the elongation at break reached the maximum value of 64.02%. However, when the Ag/MAH-g-POE content further increased to 20 wt.%, the elongation at break decreased again, which could be attributed to the aggregation of excessive Ag nanoparticles forming local defects in the POM/Ag/MAH-g-POE ternary nanocomposites. Furthermore, when the Ag/MAH-g-POE content was 20 wt.%, the maximum decomposition temperature of POM/Ag/MAH-g-POE ternary nanocomposites was 398.22 °C, which was 71.39 °C higher than that of pure POM. However, compared with POM, the storage modulus of POM/Ag/MAH-g-POE ternary nanocomposites decreased with the Ag/MAH-g-POE content, because the MAH-g-POE elastomer could reduce the rigidity of POM.

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With the environmental problems brought about by the excessive use of fertilizers and pesticides, numerous biological amendments have been developed and used in recent years. This study, through in-depth analysis of the effects of two different microbial amendments on the microbial diversity in the garlic rhizosphere, provides a theoretical basis and data support for farmers to select microbial amendments. In the experiment, two different microbial amendments were applied to garlic, and its rhizosphere soil was collected after 10, 20, 30, and 40 days. The polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze bacterial diversity in the garlic rhizosphere soil. The total abundance and diversity of microbial flora in the rhizosphere soil of garlic increased after application of microbial amendments to soil or plants. Plant growth was significantly better in the soil treatment than the plant treatment and the water control. The two dominant bacteria of uncultured gamma proteobacterium and Uncultured Gemmatimonadete existed only in the soil treatment. After 40 day of treatment, the abundance in the rhizosphere soil of these four bacterial strains (Uncultured Bacillus sp. clone D.an-22, Mesorhizobium sp., uncultured gamma proteobacterium, and Pseudomonas boreopolis) was greater in the soil than the plant treatment and the control. The irrigation of microbial amendments not only influenced the structure and abundance of rhizosphere microorganisms, and also promoted the colonization by microorganisms. The five bacterial strains of uncultured gamma proteobacterium, Uncultured Gemmatimonadetes, Uncultured Bacillus sp. clone D.an-22, Mesorhizobium sp., Pseudomonas boreopolis could facilitate the growth and enhance resistance of garlic, establishing a foundation for the use of microbial amendments and providing new ideas and methods for environmental management and protection.