用动态力学热分析仪研究胶料的动态力学性能

Study on Dynamic Mechanical Properties of Compound by DMA

用动态力学热分析(DMA)仪研究不同硫化程度的天然橡胶(NR)以及胎面胶的动态力学性能,并与差示扫描量热(DSC)仪测试结果进行比较。结果表明:DSC仪和DMA仪都可以快速、方便地测定胶料的玻璃化温度(Tg),二者测得的Tg偏差均较小;DMA仪可以得到胶料的储能模量(E′)、损耗模量(E″)和损耗因子(tanδ);通过tanδ-温度曲线可以分析胶料的抗湿滑性能、生热和滚动阻力;根据时间-温度等效原理和WLF方程可以得到胶料的频率外推曲线,曲线频率可推至测试难以达到的范围,这对分析橡胶材料在高频下的性能很有意义。

The dynamic mechanical properties of natural rubber （NR） compounds with different vulcanization degree and tread compound were studied by dynamic mechanical thermal analyzer （DMA） , and the results were compared with the testing results from differential scanning calorimetry （DSC） analysis. The results showed that the glass transition temperature （Tg） of the compound could be determined quickly and conveniently by DSC and DMA, and the deviation was small for both methods. DMA could be used to determine the storage modulus （E′） , loss modulus （E″） and loss factor （tanδ）. The rantS-temperature curve from DMA test could be used to analyze the wet-skid resistance, heat build-up and rolling resistance of the compound. In addition, based on time-temperature superposition principle and WLF equation, the obtained curve could be extrapolated to a higher frequency range which was difficult to test and it was very useful for the performance analysis of rubber materials under high frequency.