Xiawang Jiang’s research while affiliated with Hunan University of Technology and other places

The water absorption and flammability of paper pose significant challenges to its long-term effectiveness. Hence, this study introduced a paper modification strategy that synergistically incorporated both superhydrophobicity and flame retardancy. This method involved the formation of a micro or nano-level rough structure on the paper surface through sodium silicate modification. Further modification of the paper surface with polydimethylsiloxane yielded a functional paper with excellent superhydrophobic properties. The modified paper exhibited a water contact angle (WCA) and sliding angle (SA) of 153.5° and 9°, respectively, indicating excellent self-cleaning, abrasion resistance, and chemical resistance. The limiting oxygen index, thermogravimetry-derivative thermogravimetry analysis, and cone calorimeter test results indicated that the superhydrophobic paper exhibited excellent thermal stability and flame-retardant properties. These properties enhanced product safety during paper use. The comprehensive improvement in paper properties, including enhanced superhydrophobicity, flame retardancy, and thermal stability, significantly expands its application range and enhances overall utility. Graphical abstract

Ensuring sufficient mechanical performance while enabling lightweight design is critical for utilizing paper sandwich panels in the furniture industry. To design lightweight sandwich panels that balance mechanical properties and cost, this study developed a circular core paper sandwich panel (CCPSP) and investigated its structural efficiency using multi-objective optimization. The response surface method (RSM) based on Box–Behnken design was utilized to establish mathematical models relating the paper tube spacing, inner diameter, and height to the out-of-plane compressive strength, density, and cost. The resulting models effectively revealed the coupled effects of the parameters on the responses. Subsequently, the models were optimized using the non-dominated sorting genetic algorithm II (NSGA-II) to find the Pareto optimal trade-offs between maximizing compressive strength while minimizing its density and cost. The optimization solution resulted in an optimal set of paper tube geometries that maximized the structural efficiency of CCPSP. Overall, lower tube height conferred superior structural efficiency, while tube spacing and diameter were constrained. The results highlight the potential of CCPSP as an efficient and sustainable material for furniture manufacturing, enabled by multi-objective optimization of its structure.

The water absorption and flammability of paper pose significant challenges for its long-term effectiveness. In addressing these concerns, a paper modification strategy was proposed that synergistically incorporated superhydrophobicity and flame retardancy. This approach involved the formation of a micro or nano-level rough structure on the paper surface through sodium silicate modification. Subsequent modification with polydimethylsiloxane (PDMS) resulted in a functional paper, exhibiting excellent superhydrophobic properties. The water contact angle (WCA) and sliding angle (SA) of the modified paper reached 153.5° and 9°, respectively, exhibiting excellent self-cleaning ability and wear resistance. The results from TG–DTG analysis and cone calorimeter tests indicated that the superhydrophobic paper exhibited remarkable thermal stability and flame-retardant properties. These properties contributed to enhancing the safety of products during application. The comprehensive improvement in paper properties, including its superhydrophobicity, flame retardancy, and thermal stability, holds significant implications for expanding its application range and enhancing its overall utility.

Bamboo is an environmentally friendly building structural material. This work investigated the cavity structural characteristics and physical and mechanical properties of honeycomb sandwiches and natural bamboo in the longitudinal direction. The effective elastic parameters of periodically arranged hexagonal bamboo honeycomb cells under in-plane and out-of-plane loads were modeled using analytical and numerical approaches. Then, the effective elastic parameter model of bamboo honeycomb cells was validated by experiments and finite element analysis. The average errors between the calculated and experimental equivalent modulus of elasticity, Poisson’s ratio, and shear modulus in the three principal axis directions were 7.43, 4.37, and 8.68%, respectively. The average relativities between the model values of the elastic parameters of the bamboo honeycomb cell and the simulation results in the three directions were 5.46, 5.40, and 6.12%, respectively. The experimental and finite element analysis showed that the constructed effective elastic parameter model of the bamboo honeycomb cell better reflected the state of the bamboo core when subjected to force. This study provides insights for further research on the mechanical properties of bamboo materials and their application in bamboo-based lightweight and high-strength sandwich structures.

Bamboo is a kind of green and environmentally friendly building structure material. This work was based on the cavity structural characteristics and excellent physical and mechanical properties of honeycomb sandwich and natural bamboo in the longitudinal direction, the effective elastic parameters of periodically arranged hexagonal bamboo honeycomb cells (BHC) under in-plane and out-of-plane loading were modeled using analytical and numerical approaches. The equivalent density analysis of the BHC was based on the condition of double cell wall thickness. In addition, the effective elastic parameters were analyzed considering the effective bending length, axial compression, shear deformation, and bending deformation of the inclined and vertical members of BHC. Then, different sizes of hexagonal BHC were used for experiments, and the finite element method(FEM) was combined with the computational homogenization technique to validate the effective elastic parameter model of bamboo cells. The results showed that the maximum relative errors between the values of the modeled and simulated elastic parameters of the BHC and the experimental results were 8.6 and 8.7%, respectively, indicating that the constructed effective elastic parameter model better reflected the state of the stressed BHC. This study provides new insights for further research on the mechanical properties of bamboo materials and their application in bamboo-based lightweight and high-strength sandwich structures.