Maleic anhydride-modified homopolymerized polypropylene (PP-g-MAH) and maleic anhydride-modified polyolefin elastomer (POE-g-MAH) were used as bulking agents to improve the poor processing and mechanical properties of highly filled composites due to high filler content. In this study, a series of linear low-density polyethylene (LLDPE)/magnesium hydroxide (MH) composites were prepared by the melt blending method, and the effects of the compatibilizer on the mechanical properties, flame retardancy, and rheological behavior of the composites were investigated. The addition of the compatibilizer decreased the limiting oxygen index (LOI) values of the composites, but they were all greater than 30.00%, which belonged to the flame retardant grade. Mechanical property tests showed that the addition of the compatibilizer significantly increased the tensile and impact strengths of the LLDPE/60MH (MH addition of 60 wt%) composites. Specifically, the addition of 5 wt% POE-g-MAH increased 154.07% and 415.47% compared to the LLDPE/60MH composites, respectively. The rotational rheology test showed that the addition of the compatibilizer could effectively improve the processing flow properties of the composites. However, due to the hydrocarbon structure of the compatibilizer, its flame retardant properties were adversely affected. This study provides a strategy that can improve the processing and mechanical properties of highly filled composites.

To address the high flammability and toxic smoke emission of flexible PVC (fPVC), a Mg–Mo–P multi-component flame retardant (MO@MH-PEPE) was constructed by modifying MoO ₃ -hybridized Mg(OH) ₂ with phenolic epoxy phosphate ester.

A simple hydrothermal method was developed in this study to synthesize hydrophobic calcium sulfate hemihydrate whiskers in the presence of stearic acid. The morphology of the whiskers synthesized under different conditions was characterized by scanning electron microscopy, and their average aspect ratio was also estimated. The optimum synthesis conditions are determined as follows: the concentrations of Na2SO4 and CaCl2 solution for preparing the precursor are 1.1 mol/L; the precursor content in the autoclave is 10 wt％; the hydrothermal reaction temperature is 150 C; and the hydrothermal reaction time is 4 h, respectively. Glycol was used to promote the dispersion of stearic acid in the seriflux. The results show that the hydrophobic calcium sulfate hemihydrate whiskers can be obtained with stearic acid as surfactant, and their average aspect ratio can reach about 91.