【摘要】 通过磁共振交联密度仪、衰减全反射傅里叶变换红外光谱仪和动态力学分析仪,对未填充天然橡胶(NR)硫化胶在拉伸疲劳前后结构及动态黏弹性的变化进行了研究。结果表明,未填充NR硫化胶的交联密度随拉伸疲劳时间的延长先增大后减小,拉伸强度和100%定伸应力在拉伸疲劳后期明显下降;未填充NR硫化胶在拉伸疲劳后生成了共轭二烯、三烯类结构,并导致拉伸疲劳后未填充NR硫化胶在高弹区的储能模量大幅度下降,损耗因子则随拉伸疲劳时间的延长明显增高。更多还原

【Abstract】 The effect of dynamic tensile fatigue on structure and dynamic viscoelasticity of unfilled natural rubber(NR) vulcanizates was investigated by magnetic resonance crosslink density spectrometry,Fourier transform infrared spectroscopy-attenuated total reflectance and dynamic mechanical analysis.The results showed that the crosslinking density of unfilled NR vulcanizate increased first and then decreased,tensile strength and modulus at 100% declined significantly with the extension of the time of tensile fatigue.Conjugated diene,triene appeared in the network structure after tensile fatigue,which resulted in storage modulus declined sharply while loss factor increased obviously.更多还原