紫外线对沥青特征官能团和玻璃化温度的影响

Impact of ultraviolet radiation on changes of typical functional groups and vitrification temperature for asphalts

为了评价紫外线老化对沥青性质的影响,利用红外光谱和差示扫描量热分析方法,研究了不同紫外线老化时间对沥青特征官能团和玻璃化转变温度的影响。通过试验分析,得到紫外线老化0、240 h、720 h、1200 h与沥青特征官能团吸收峰强度及玻璃化转变之间的关系。结果表明:基质沥青经240 h紫外线老化即达深度老化,羰基和亚砜官能团吸收峰强度最大,而比热容和玻璃化转变温度最小,如继续老化,则其羰基、亚砜官能团、比热容和玻璃化温度变化趋于平缓;SBS改性沥青深度老化速度远慢于基质沥青。

In order to evaluate the impact of ultraviolet on the asphalts, the influence of ageing times on typical functional groups and vitrification temperature of asphalt was studied by using infrared adsorption spectrum analysis （IR spectra） and differential scanning calorimetry （DSC）. Through analyzing the test results, the relationships of different ageing times, such as 0 h, 240 h, 720 h and 1 200 h, with the highness of IR absorbing peak of typical functional groups and vitrification for asphalts were obtained. The results show that basic asphalt gets obvious ageing and the changes of carbonyl absorbing peak and sulfoxide absorbing peak are remarkable after 240 h irradiation of ultraviolet. In the meantime, specific heat capacity and vitrification temperature for basic asphalt become the lowest. When the ageing goes on, the changes of carbonyl group, sulfoxide group, specific heat capacity and vitrification temperature for basic asphalt tend to be slow. The time of tough ageing for SBS modified asphalt is obviously late in contrast with basic asphalt. 2 tabs, 4 figs, 10 refs.