表面修饰纳米二氧化硅对沥青性能的影响

Effect of Nano-SiO_2 with Modified Surface on Properties of Bitumen

研究了表面修饰纳米Si0_2对沥青物理性能和紫外老化性能的影响,并通过高温储存稳定性试验探讨了纳米SiO_2与沥青的相容性.结果表明:纳米SiO_2的表面修饰显著增强了其与沥青的相容性,相同掺量下,表面修饰纳米SiO_2改性沥青的软化点差值以及离析管上下两部分纳米SiO_2含量的差值均要低于未修饰纳米SiO_2改性沥青.与未修饰纳米SiO_2相比,表面修饰纳米SiO_2对沥青的软化点和黏度提高幅度更大,针入度降低更小,且可提高沥青10℃的延度.同时,表面修饰纳米SiO_2改性沥青紫外老化后的黏度老化指数显著减小,表现出优良的耐紫外老化性能.

Effect of nano-SiO2 with modified surface on the physical and ultraviolet aging resisance of bitu- men was investigated. The eompatibility between nano-SiO2 and bitumen was studied by high temperature stability test. The results show that the compatibility between nano-SiO2 and bitumen is improved signifi- cantly by surface modification of nano-SiO2. With the same nano-SiO2 content, the difference values of sof- tening point as well as the nano-SiO2 contents in the upper and lower sections of the toothpaste tubes for the bitumen with unmodified nano-siliea are lower than that for the bitumen with unmodified nano-SiO2. Compared with modified nano-SiO2, the softening point and viscosity of bitumen are increased by adding modified nano-silica more significantly, moreover, the penetration is less reduced and the ductility of bitu- men is increased by 10 ℃. In addition, by using modified nano-siliea the viscosity aging index of the bitu- men is reduced significantly after ultraviolet aging indicating good ultraviolet aging resistance of bitumen with surface modified nano-SiO2.