废胶粉改性制备高模量沥青及其动态力学性能

Preparation and Dynamic Mechanical Properties of High-Modulus Asphalt Modified by Waste Rubber

以脱油沥青(DOA)为主要原料,分别掺加不同粒径和不同含量的废胶粉制备高模量沥青,并对产物进行常规指标分析、动态力学性能分析及荧光显微检测。研究结果表明,胶粉在沥青中主要以条状或棒状形式存在,且胶粉与沥青并不完全相容,而是以分散相分散在沥青中。随着胶粉掺量的增加,高模量沥青的软化点逐渐上升,其高温性能得到明显改善,这是由于废胶粉吸收沥青中的轻质组分后发生溶胀,沥青质含量增加,使得高模量沥青组分重质化。相同温度下,G*、G′和G″均随废胶粉掺量的增加呈现明显上升的趋势,说明废胶粉掺量越高,沥青模量的改善效果越明显,对高模量沥青的抗车辙性能越有利;通过拟合不同废胶粉掺量下G*/sinδ与温度的关系,计算得到每增加1%(质量分数,下同)的废胶粉,高模量沥青的高温等级增加1.66℃。

With de-oiled asphalt(DOA)as the main raw material,waste rubber powder of different particle size and contents was added respectively to prepare high-modulus asphalt.Conventional properties analysis,dynamic mechanical analysis and fluorescence microscopy were performed for the products.Results show that rubber powder is not completely compatible with the asphalt but dispersed in the asphalt in the form of dispersed phase existing in the asphalt in the form of strip or rod.With the increase of rubber amounts,softening point increases gradually and the high-temperature performance is obviously improved.It is caused by the swelling of waste rubber powder after absorbing the light part of asphalt and the increase of asphaltene content.At the same temperature,G*,G′and G″all showed an obvious upward trend with the increase of waste rubber content,indicating more obvious of improvement effect and more favorable rutting resistance of high-modulus asphalt with the higher the waste rubber powder content.By fitting the relationship between G*/sinδand temperature under different waste rubber amount,the high tempe-rature grade of high-modulus asphalt increases by 1.66℃for every 1wt%increase of waste rubber.