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Herein, the performance of silicone-modified 3D printing photosensitive resin was examined. Bisphenol-A epoxy acrylate (EA) was used as the substrate and isophorone diisocyanate, hydroxy-silicone oil, and hydroxyethyl acrylate were used as the raw materials. A silicone intermediate was synthesized to modify the substrate to prepare the 3D printing photosensitive material. The as-synthesized materials were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The tensile fracture morphology was also analyzed. The effects of the addition of silicone intermediates on the mechanical properties, thermal stability, and shrinkage of the prepared 3D printing photosensitive resins were investigated. The results showed that an organosilicone group was successfully introduced into the side chain of EA. When the ratio of n(silicone):n(EA) is 0.3:1, the material has a high impact strength of 19.4 kJ·m−2, which is 32.8% higher than that of the pure resin; in addition, the elongation at break is 8.65% (compared to 6.56% of the pure resin). The maximum thermal weight loss temperature is 430.33°C, which is 6°C higher than that of the pure resin.

Light‐curing rapid prototyping (SLA) has become an emerging technology in the manufacturing industry because of its high precision, rapid prototyping, and the ability to mold complex parts. To enhance the mechanical properties and thermal stability of its raw material photosensitive resin (PR), carbon fiber (CF) was surface modified by chemical oxidation and grafting of amino silane (KH550) to obtain KH550‐modified carbon fiber (ACF). Then, ACF was composited with photosensitive resin to obtain modified carbon fiber/photosensitive resin (ACF/PR) composites. The viscosities of ACF/PR composites, including the viscosity, curing shrinkage, mechanical properties, and thermal stability of the ACF/PR composites, were characterized. The results showed that KH550 was successfully grafted onto CF. When the addition of ACF in the composites was 0.6%, the tensile strength, elongation at break, and impact strength of ACF/PR reached 39.48 MPa, 20.32%, and 13.62 kJ/m2, which were 120%, 27.15%, and 154% higher than that of the pure resin; the thermal decomposition temperatures and the maximum thermal decomposition temperatures at 50% mass loss of ACF/PR increased to 457.66°C and 442.44°C at 50% mass loss, which is 3.95% and 3.63% higher than that of the pure resin. Currently, the composites have excellent strength, toughness, and thermal stability. This paper gives a cost‐efficient method for improving the functioning of PR. Highlights: Mixed acid oxidation and amino silane modification of CFs.Preparation of modified CF/photosensitive resin composites.Composites with excellent mechanical properties and thermal stability. [ABSTRACT FROM AUTHOR]

This paper investigates the preparation of spherical molybdenum-copper (Mo-Cu) composites through the utilization of plasma spheroidization1 of molybdenum powder, followed by ‘Carbon thermal pre-reduction + Hydrogen deep reduction2’ processes. The properties of these composites are analyzed. By adjusting the mass ratio of molybdenum to copper and employing mechanical activation during high-temperature sintering, Mo and Cu are dispersed more uniformly, resulting in improved fluidity and a reduced tendency to agglomerate in x% Mo-Cu (x = 20, 40, 60, 80) composites. Experimental results demonstrate that compared to original powder Mo-Cu composites, the prepared spherical Mo-Cu composites exhibit uniform elemental distribution, regular arrangement, and reduced porosity. Among these, the 60% Mo (spherical)-Cu composites show the best dispersion and superior performance. At the optimal sintering temperature of 1250°C, the thermal conductivity of the sintered product increased from 137 Wm−1K−1 to 148 Wm−1K−1, the electrical conductivity increased from 18.9 MS/m to 21.8 MS/m, and the Vickers hardness increased from 177 HV to 209 HV. [ABSTRACT FROM AUTHOR]

Electromagnetic waves can cause different degrees of damage to the human body. People are developing unique nanomaterials with excellent reflection loss (RL), thin thickness, wide frequency band and light weight to improve the absorption efficiency of electromagnetic waves. Using a hydrothermal method, ZnO nanocrystals are combined with graphene oxide (GO). After heat treatment, evenly dispersed ZnO nanocrystals are attached to the GO surface or inserted into the lamellae, and the amount of Zn(CH3COO)2·2H2O and GO is selected to obtain ZnO/RGO nanocomposites with different mass ratios (1 : 1, 1 : 2, 1 : 3). The ZnO/RGO nanocomposites were mixed with paraffin wax with different mass ratios (15, 20, 25, 30 wt%) to explore their electromagnetic parameters and wave absorption properties. It is found that at 25 wt%, ZnO : GO = 3 : 1 and thickness of 3 mm, the sample exhibits excellent wave absorption performance (−36.6 dB) and wide effective absorption bandwidth (6.6 GHz). The microwave absorption performance is enhanced because ZnO nanocrystals inhibit RGO agglomeration and improve impedance matching between the heterostructure interface and RGO. [ABSTRACT FROM AUTHOR]