Yanbei Hou

Effect of cuprous oxide with different sizes on thermal and combustion behaviors of unsaturated polyester resin

Cuprous oxide (Cu2O) as an effective catalyst has been applied to enhance the fire safety of unsaturated polyester resin (UPR), but the particle size influence on combustion behaviors has not been previously reported. Herein, the UPR/Cu2O composites (metal oxide particles with average particle-size of 10, 100, and 200nm) were successfully synthesized by thermosetting process. The effects of Cu2O with different sizes on thermostability and combustion behaviors of UPR were characterized by TGA, MCC, TG-IR, FTIR, and SSTF. The results revel that the addition of Cu2O contributes to sufficient decomposition of oxygen-containing compounds, which is beneficial to the release of nontoxic compounds. The smallest-sized Cu2O performs the excellent catalytic decomposition effect and promotes the complete combustion of UPR, which benefits the enhancement of fire safety. While the other additives retard pyrolysis process and yield more char residue, and thus the flame retardancy of UPR composites was improved. Therefore, catalysis plays a major role for smaller-sized particles during thermal decomposition of matrix, while flame retarded effect became gradual distinctly for the larger-sized additives.

Bi2Se3 decorated recyclable liquid-exfoliated MoS2 nanosheets: towards suppress smoke emission and improve mechanical properties of epoxy resin

Bimetallic compounds have been proved superior suppression effect on smoke emission during combustion of polymers. In this work, MoS2/Bi2Se3 (MB) hybrids were prepared by a facile wet chemical method and showed superior performance on smoke suppression of EP matrix during combustion. N-vinyl pyrrolidone (NVP) was employed to exfoliate molybdenum disulfide (MoS2) nanosheets in a recyclable method, which showed high efficiency and was recyclable. Exfoliated MoS2 exhibited large surface area and used as carriers to synthesize MB hybrids. Considering the catalytic effect of bismuth and molybdenum, the hybrids had a great influence on the smoke emission behaviors of EP composites. The smoke production was obviously suppressed during the flaming combustion (more than 22% and 23% decrease obtained from cone calorimeter and steady state tube furnace, respectively) or smolder processes (more than 23% decrease obtained from smoke chamber) at only 1 wt% content of MB hybrids. Whats more, due to superior dispersion state, the addition of MB hybrids also enhanced the mechanical properties of EP matrix, including wear resistance and tensile property. This work provided a safe and green exfoliation method of MoS2 to prepare polymers/MoS2 composites and also constructed a novel binary hybrids for enhancing combination performances of polymers.