UV-531和纳米TiO_2对沥青抗紫外老化性能的影响

Effect of UV-531 and Nano-TiO_2 on Ultraviolet Radiation Aging Performance of Asphalt

为了改善沥青抗紫外老化性能,研究了3个掺量(0.4%、0.7%、1.0%)的紫外光吸收剂和纳米二氧化钛对SBS改性沥青基本性能及其抗紫外老化性能的影响,采用熔融共混的方法制备了UV-531/SBS改性沥青和纳米TiO_2/SBS改性沥青,通过三大指标试验对比评价两种材料对SBS改性沥青高低温性能的影响。结果表明:两种材料均能提高SBS改性沥青的软化点和针入度,但效果不明显;它们对延度的影响程度不一,紫外光吸收剂使SBS改性沥青的延度最大提高了58.35%,纳米二氧化钛使其延度最大降低了13.49%。对改性沥青进行紫外老化,并对紫外老化前后的沥青进行DMA试验、DSR试验和红外光谱试验,试验结果表明:紫外老化后,每种改性沥青的高温稳定性明显提高,且当掺入1.0%的紫外光吸收剂和0.7%的纳米二氧化钛时,SBS改性沥青表现出较好的低温性能,抗紫外老化能力由大到小依次为A_(1.0)>B_(0.7)>SBS。

In order to improve the anti UV aging properties of asphalt,the effects of UV absorbent and Nano-TiO2 materials with three doses(0.4%,0.7%,1%) on the basic properties and anti ultraviolet radiation aging properties of SBS modified asphalt are studied comparatively,UV-531/SBS and NanoTiO2/SBS modified asphalt are prepared by melting and blending method,the effect of two kinds of materials on the high and low temperature performance of SBS modified asphalt is evaluated by three index tests.The results show that both the two materials can improve the softening point and penetration of asphalt,but the effect is not obvious;the degree of their influence on ductility is different,UV absorbents increase the ductility of SBS modified asphalt by 58.35%,and Nano-TiO2 decreases the ductility by 13.49%.Ultraviolet aging test is carried out on modified asphalt,dynamic thermo mechanical analysis (DMA) test,dynamic shear rheometer (DSR) test and infrared adsorption spectrum analysis are carried out on the modified asphalt before and after ultraviolet aging.The test results show that:after UV aging,the high temperature stability of each modified asphalt is significantly improved,and SBS modified bitumen shows good low temperature performance when adding 1% UV absorbents and 0.7% Nano-TiO2,and the anti-aging ability of the modified asphalt is A1.0>B0.7>SBS.