聚苯乙烯接枝胶粉对改性沥青性能的影响  

Impacts of polystyrene grafting modified crumb tire rubber on the property of modified bitumen

作　　者：张寅清 张琛 李翠红 李彤彤[1] 张楠[1] 汪锦 于凯[1] 刘双喜 ZHANG Yinqing;ZHANG Chen;LI Cuihong;LI Tongtong;ZHANG Nan;WANG Jin;YU Kai;LIU Shuangxi(College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China;School of Materials Science and Engineering,Nankai University,Tianjin 300350,China)

机构地区：[1]南开大学环境科学与工程学院,天津300350 [2]南开大学材料科学与工程学院,天津300350

出　　处：《环境工程学报》2020年第2期490-497,共8页Chinese Journal of Environmental Engineering

基　　金：国家高技术研究发展计划(863计划)(2012AA063008);天津市应用基础与前沿技术研究计划项目(15JCTPJC63500,17JCYBJC22600)。

摘　　要：采用苯乙烯对废轮胎胶粉进行表面接枝聚合改性,并将接枝改性胶粉用于制备湿法胶粉改性沥青。接枝改性后,废轮胎胶粉的X射线光电子能谱和13C固体核磁检测结果表明,苯乙烯链段成功接枝到废轮胎胶粉表面,同时系统研究了苯乙烯接枝率对胶粉改性沥青25℃针入度、软化点和5℃延度的影响规律。实验结果表明,当苯乙烯接枝率小于36%时,随着苯乙烯接枝率的提高,胶粉改性沥青的25℃针入度和5℃延度增大,软化点下降,说明胶粉表面苯乙烯链段的接枝,能够显著提高胶粉-沥青的界面相容性;当苯乙烯接枝率为36%时,胶粉改性沥青的5℃延度达到11.0 cm,相比于普通胶粉改性沥青(7.0 cm)提高了57%;但当苯乙烯接枝率大于36%时,随着苯乙烯接枝率的提高,胶粉改性沥青的25℃针入度和5℃延度下降,软化点升高,表明胶粉-沥青界面层中过量的聚苯乙烯链段,使胶粉改性沥青的低温延展性有所降低。通过分析可知,在胶粉表面接枝适当比例的聚苯乙烯能够显著改善胶粉改性沥青的低温延展性能。The crumb tire rubber(CTR) was grafting modified by styrene and the modified CTR was used to prepare the rubber modified bitumen. The XPS and 13 C solid state NMR characterizations of modified CTR confirmed the successful grafting of styrene on CTR. The effects of the styrene grafting ratio on the 25 ℃penetration, softening point, and 5 ℃ ductility of rubber modified bitumen were investigated. The results showed that with the increase of grafting ratio of polystyrene(<36%), 25 ℃ penetration and 5 ℃ ductility of the polystyrene grafting rubber modified bitumen increased, while its softening point decreased, which indicated that the grafting of polystyrene could improve the interface compatibility between CTR and bitumen. At the grafting ratio of styrene of 36%, the 5 ℃ ductility of the polystyrene grafting rubber modified bitumen reached11.0 cm, which was 57% higher than that of original rubber modified bitumen(7.0 cm). However, at the grafting ratios of styrene above 36%, its 25 ℃ penetration and 5 ℃ ductility decreased, while its softening point increased, which indicated that excessive polystyrene chains on the interface between crumb tire rubber and bitumen led to the decrease of ductility and malleability of rubber modified bitumen. According to all the analysis, it can be concluded that the proper amount of polystyrene grafting can significantly improve the low temperature performance of rubber modified bitumen.

关 键 词：废轮胎 胶粉 聚苯乙烯 接枝率 改性沥青 

分 类 号：X734.2[环境科学与工程—环境工程]