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To improve the flame retardancy of low‐density polyethylene (LDPE) and mechanical properties of LDPE composites, phenol‐formaldehyde aluminum diethylphosphinate microcapsules (PF@ADP) was prepared by in‐situ polymerization with phenol‐formaldehyde (PF) resin as the wall material and halogen‐free flame‐retardant aluminum diethylphosphinate (ADP) as the core material. The effects of PF@ADP on flame retardancy and mechanical properties of LDPE were investigated by methods of combustion experiments, mechanical analysis, thermogravimetric analysis (TGA), and smoke density analysis. The results indicated that, compared with ADP/LDPE composites, the flame retardancy and mechanical properties of PF@ADP/LDPE were obviously improved. With the addition of 20 wt% PF@ADP (PF:ADP = 3:7), the limit oxygen index (LOI) of LDPE composites increased to 30.7% and UL‐94 reached V‐1 grade. The tensile strength and elongation at break reached 12.5 MPa and 431.2%, which was 20.2% and 23.1% higher than that of ADP/LDPE with the same addition. The addition of PF@ADP was beneficial to the smoke suppression of LDPE.

To investigate the international development status and hot trends in the field of environmental security management in recent years, the published the environmental security management literature from 1997 to 2021, which was retrieved from Web of Science, with VOSviewer as the main and CiteSpace as the auxiliary, through the cooperation network of authors, scientific research institutions, and countries. The keywords were visualized by clustering, time zone analysis, and burst analysis. A total of 7596 articles were retrieved, forming six main clustering labels, including 28,144 authors. The research hotspots are from the fields of personal health, society, agriculture, ecological environment, energy, and sustainable development, as well as the development of internet environmental safety management, such as big data, Bayesian networks, and conceptual frameworks. Through cluster analysis, the cooperation of major research teams and scientific research institutions and the cooperation and development between countries were analyzed. The cooperation between scientific research institutions in various countries is relatively close. The United States currently occupies a dominant and authoritative position in this field. China has cooperated more closely with the United States, Britain, Australia, and India.

As a natural plant material with unique porous structure, loofah is used in many fields, but there are still defects in fire safety performance in that its flammability. The melamine-modified flame retardant loofah composites (M-FR-PL) were prepared by impregnation baking method. The experimental synthesis conditions were optimized by L9 (34) orthogonal design. The flame retardancy, heat release rate (HRR), thermal stability and smoke density of the composites were analyzed. M-FR-PL6 prepared under the optimum experimental conditions had good properties: the adsorption rate of flame retardant (AR, %) was 6.8%, the limiting oxygen index (LOI, %) reached 27.5%, the vertical combustion level reached V-0, and the amount of residual char was 17.2% higher than that of loofah. The flame retardant mechanism of M-FR-PL6 was thoroughly discussed by various characterization methods. The peak of the HRR curve of M-FR-PL6 declined compared with loofah, indicating the loofah after melamine flame-retardant treatment has good flame retardancy and smoke suppression properties.

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