聚氨酯轨下垫板制备及性能对比研究

Preparation and Performance Comparison Study of Polyurethane Underrail Pad

为了优化聚氨酯轨下垫板制作工艺,采用高压混合成型和低压混合成型工艺分别制备聚氨酯轨下垫板,进行了力学性能、红外光谱分析、动态力学分析、热失重分析以及扫描电镜测试,并与市售产品进行对比。结果表明:制备的两种聚氨酯轨下垫板性能均满足相关标准要求,与市售产品性能相当,且低温性能更优异;相比于低压混合成型工艺,采用高压混合成型工艺制备的轨下垫板泡孔直径更小(50μm),分布更均匀,具有更好的力学性能,且压缩永久变形和动静刚度比更低,分别为3.8%和1.29;相同配方的聚氨酯材料热失重后残碳量相同,但不同阶段分解温度有所差异,玻璃化转变温度也不同,制成的轨下垫板在使用温度下表现出的弹性和阻尼性能也不同。建议采用高压混合成型工艺制备聚氨酯轨下垫板。

In order to optimize the production process of polyurethane underrail pad,polyurethane underrail pad were prepared by a high-pressure and low-pressure mixed molding process.Mechanical properties,infrared spectroscopy analysis,dynamic mechanical analysis,thermogravimetric analysis,and scanning electron microscopy testing were carried out,and compared with commercially available products.The results show that the performance of the two types of prepared polyurethane underrail pad meet the relevant standard requirements,are comparable to the performance of products on the market and had better low-temperature performance.Compared to the low-pressure mixing molding process,the foam hole diameter of the underrail pad prepared by the high-pressure mixing molding process is smaller(50μm),with more uniform distribution,better mechanical properties,and lower compression permanent deformation and dynamic static stiffness ratio of 3.8%and 1.29,respectively.The residual carbon content of polyurethane materials with the same formula after thermal weight loss is the same,but there are differences in the decomposition temperature and glass transition temperature at different stages.The elastic and damping properties of the underrail pad made from it are also different at the operating temperature.It is recommended to use high-pressure mixing molding technology to prepare polyurethane underrail pad.