用钛酸酯偶联剂对氢氧化镁（MH）进行改性，并制备聚氨酯/氢氧化镁（PU/MH）复合材料，研究了复合材料的力学性能和燃烧行为。结果表明：随着MH掺量增加，复合材料的压缩强度逐渐增大，复合材料的抗拉强度和弯曲变形逐渐降低。随着MH掺量增加，复合材料的点燃时间（TTI）和质量残余率（MLR）逐渐增大，总热释放量（THR）、总烟释放量（TSR）、CO生成量和CO₂生成量逐渐降低，复合材料的燃烧等级从V-2提高到V-0。MH掺量为30%时，复合材料的力学性能和阻燃性能均较好。4#复合材料的抗压强度比纯PU提高45.0%，抗拉强度和弯曲变形分别降低10.0%和5.3%，燃烧等级从V-2提高到V-0，CO和CO₂总生成量分别降低50.0%和22.2%。

Polyurethane/magnesium hydroxide (PU/MH) composites were prepared by modifying magnesium hydroxide (MH) with titanate coupling agent. The mechanical properties and combustion behavior of the composites were studied. The results show that with the increase of MH content, the compressive strength of the composites increases gradually, and the tensile strength and bending deformation of the composites decrease gradually. With the increase of MH content, the ignition time (TTI) and mass residual rate (MLR) of the composites increase gradually, the total heat release (THR), total smoke release (TSR), CO generation and CO₂ generation of the composites decrease gradually, and the combustion grade of the composites increases from V-2 to V-0. When the MH content is 30%, the mechanical properties and flame retardancy of 4# composite are good. Compared with pure PU, the compressive strength of 4# composite is increased by 45.0%, the tensile strength and bending deformation are decreased by 10.0% and 5.3%, respectively, the combustion grade increases from V-2 to V-0, and the total CO and CO₂ production are decreased by 50.0% and 22.2% respectively.