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As epoxy resin (EP) is widely used in the microelectronic field, it is essential to improve its electromagnetic wave (EMW) absorption and flame retardancy simultaneously. In this work, we synthesized a novel nanohybrid, RMN (Fe 3 O 4 /NHS@M(OH)(OCH 3)@rGO (M = Co, Ni)), with petal-shaped anisotropic interfaces, by using graphene oxide as the core and the 2D nanosheets M(OH)(OCH 3) (M = Co, Ni) as the petal, with nickel hydroxystannate and ferrite as further modifications. The RMN combines carbon-based materials, ferrites and conductors, and represents the petal-like structure with rich nondirectional interfaces. The results show that EP composite containing 25 wt% RMN represented excellent EMW absorption, with a minimum reflection loss of −55.79 dB (with 7.4 mm thickness at 3.1 GHz). Moreover, the EP composite with 15 wt% RMN (EP/RMN700-3) had the lowest peak heat release rate of 470.9 kW m−2, which was 69.7 % lower than pure EP, showing a significantly improving in flame retardant. The thermal conductivity efficiency of EP/RMN700-3 increased to 128.4 % compared with the pure EP, which effectively reduces fire risk caused by heat accumulation. This study provides a valuable solution to overcome the challenges of EMW absorption and flame retardant for EP in the microelectronic materials field. [Display omitted] • The nonoriented petal-like structure provides rich interface. • Carbon materials, ferrites and conductors support the multiple absorbing mechanisms. • EMW absorption, flame retardant and thermal management suit for electronic packaging. [ABSTRACT FROM AUTHOR]

Fire alarm systems are essential for protecting lives and properties from fire hazards. However, most of the existing fire alarm nanopapers rely on the resistance reduction after heating, which requires direct contact with the flame. In this study, we present a novel fire alarm nanopaper (CMPA) based on heat-triggered shape recovery. The CMPA is composed of hydroxypropyl methyl cellulose (HPMC) as the matrix and 2D nanomaterials M(OH)(OCH 3) as fillers. When the temperature of CMPA exceeded the glass transition, the thrice-folded CMPA-1.0 flattened in 30s and connected to the alarm circuit based on its conductive surface. According to the results, the CMPA-1.0 with a thickness of about 0.2 mm had an efficient electromagnetic shielding of 42.1 dB. Moreover, the CMPA-1.0 self-extinguished rapidly after being ignited with its original shape preserved. The peak heat release rate of CMPA-1.0 was 108.9 W/g, which was 61.9 % lower than that of HPMC. Furthermore, the thermal conductivity of CMPA-1.0 reached to 0.317 W m−1 K−1, which was 40.8 % higher than that of HPMC, reducing the heat accumulation effectively. This work shows that CMPA is an ideal material for sensitive and safe early fire alarm, and the strategy based on heat-triggered shape recovery is promising in fire alarm application. [ABSTRACT FROM AUTHOR]