Conductive polymer composites (CPCs) filled with carbon-based materials are widely used in the fields of antistatic, electromagnetic interference shielding, and wearable electronic devices. The conductivity of CPCs with a carbon-based filling is reflected by their electrical percolation behavior and is the focus of research in this field. Compared to experimental methods, Monte Carlo simulations can predict the conductivity and analyze the factors affecting the conductivity from a microscopic perspective, which greatly reduces the number of experiments and provides a basis for structural design of conductive polymers. This review focuses on Monte Carlo models of CPCs with a carbon-based filling. First, the theoretical basis of the model’s construction is introduced, and a Monte Carlo simulation of the electrical percolation behaviors of spherical-, rod-, disk-, and hybridfilled polymers and the analysis of the factors influencing the electrical percolation behavior from a microscopic point of view are summarized. In addition, the paper summarizes the progress of polymer piezoresistive models and polymer foaming structure models that are more relevant to practical applications; finally, we discuss the shortcomings and future research trends of existing Monte Carlo models of CPCs with carbon-based fillings.

This work focuses on the hydrothermal aging of two-dimensional layered Ti₃C₂T_x (MXene)/epoxy (EP) nanocomposites. MXene/EP composites were successfully prepared by homogeneously dispersing multilayer MXene (m-MXene) and few-layer MXene (f-MXene) into the curing agent, methyl nadic anhydride (MNA). Considering the application, the MXene loading was designed to be 0.1 wt.%. Characterization included the characteristics of MXene, the water absorption behavior of the resin and composite samples, the glass transition temperatures (T_g) in various states, and the tensile strength evolution during aging. The curing behavior of the MXene composites was also discussed to facilitate an understanding of the processability. The results showed that MNA can chemically bond with MXene to obtain a stable suspension. The addition of MXene increased the curing characteristic temperature of the system, but the change in the activation energy of the curing reaction was minimal. The addition of MXene decreased the crosslink density of the epoxy resin, leading to a decrease in the T_g value of the initial samples. After hydrothermal aging, the T_g of pure EP decreased by 46.9 °C, and re-drying the samples did not fully restore the T_g. However, the T_g of the MXene/EP system decreased by only 8.9 °C (m-MXene) and 9.5 °C (f-MXene), respectively, and the T_g values of the samples were fully restored to their pre-aging levels via re-drying. Experiments with immersion at 25 °C and 100 °C showed that the difference in water absorption behavior between the MXene/EP and pure EP systems was minimal. Tensile tests showed that the addition of MXene increased the initial strength of the resin system by 14.7% (m-MXene) and 20.9% (f-MXene). After 400 h of hydrothermal aging, the tensile strength retention of the pure EP samples was 69.1%, while the strength retention of the MXene/EP samples was 85.3% (m-MXene) and 83.0% (f-MXene). The combined results demonstrate that the addition of MXene with a low loading of only 0.1% can effectively improve the hydrothermal resistance of epoxy resins.

In view of the situation, mask base cloth can’t be degraded naturally and there is rapid development of green fiber, cellulose acetate (CA) and polylactic acid (PLA) were used to prepare spunlaced mask base cloth to solve the problems of high energy consumption and non-recycling during producing. Mechanical property, air permeability, moisture permeability, softness, micro structure characterization and water absorption were studied and analyzed. Taking air permeability and flexural rigidity as target values, spunlaced CA/PLA base cloth was optimized by orthogonal test. The results show that when surface density is 60 g/m², thickness less than 1.2 mm, and blending ratio of CA to PLA = 50:50, the air permeability is the best; when CA to PLA is 25:75, the flexural rigidity is the worst.