基于剪切增稠胶的阻尼材料动态力学性能研究

Study on dynamic mechanical property of damping material based on STG

利用Haake转矩流变仪结合压片工序制备了不同纳米填料填充的剪切增稠胶/热塑性聚氨酯(STG/TPU)复合材料。利用扫描电子显微镜和动态热机械分析仪研究复合材料的微观结构和动态力学性能(例如玻璃化转变温度Tg、动态模量和损耗因子)。结果表明:STG与TPU的工艺相容性较好,可形成宏观均相、微观非均相的体系;温度谱显示共混聚合物的Tg向低温方向发生移动且在Tg下呈现较高阻尼峰值,有效阻尼温度范围ΔT0.7超过40℃;频率谱表现出材料低频下隔振所需的高阻尼性能;在室温下添加同等体积分数的短玻璃纤维(GF)比SiO2颗粒更能有效增强阻尼效果,这结论与提出的分析预测模型数据存在合理的一致性。这种高阻尼、宽温域、宽频带的聚合物材料展现出广阔的应用前景。

Shear-thickening gel(STG)/thermoplastic polyurethane(TPU)composites filled with different nanofillers were prepared by Haake torque rheometer combined with tableting process.The microstructure and dynamic mechanical properties[such as glass transition temperature(Tg),dynamic modulus and loss factor]of the composites were investigated by scanning electron microscopy and dynamic thermomechanical analyzer.The results confirmed that the process of STG and TPU had good compatibility and could form macro-homogeneous and micro-heterogeneous system.The temperature spectrum showed that the polymer blend exhibited a higher damping peak at Tgwhich shifted toward low temperature,and its effective damping temperature range(ΔT0.7)exceeded 40℃.The frequency spectrum showed the high damping performance required for vibration isolation at low frequencies.It suggested that adding short glass fiber(GF)at room temperature was more effective than silica(SiO2)particles with the same volume fraction in enhancing the damping effect which was reasonably consistent with the proposed analytical prediction model data.This high-damping,wide-temperature,wide-band polymer material exhibited broad application prospects.