反应型SBS复配高黏改性沥青研制与微观分析

Preparation of the Reactive High Viscosity Modified Asphalt with Composite Modifier and its Microscopic Characteristics

为克服传统高黏高弹改性剂单价高、掺量大的弊端,文中从复合材料的界面理论出发,采用反应型共混技术,制备以SBS为主要改性剂的高黏改性沥青,首先通过试验分析了基质沥青、SBS改性剂聚合方式及复配比例、促溶剂和化学稳定剂对高黏改性沥青性能的影响,确定了反应型复配SBS高黏改性沥青材料的掺配比例,并采用荧光显微镜和红外光谱试验分析了其分布及反应特征,最后对反应型复配SBS高黏改性沥青的老化性能及存储稳定性进行了全面评价。研究结果表明:采用反应型复配改性技术可以制得造价低、性能好的高黏改性沥青;当基质沥青的沥青质/芳香分比值在23%左右时,其制备的SBS高黏改性沥青具有较好的高温性能;不同聚合方式的SBS改性剂的复配可以降低SBS改性剂的掺量,线型SBS1301与星型SBS4303最佳复配比例为2∶1;且当复配改性剂掺量为6.0%、稳定剂和增溶剂的剂量分别为0.10%和5.0%时可以取得最优改性效果;微观分析发现掺加化学稳定剂制得的反应型高黏改性沥青中聚合物分散的较为均匀,形成了细密的网状结构,且SBS聚合物与基质沥青之间发生了一定程度的化学反应;旋转薄膜烘箱试验及离析试验表明反应型复配SBS高黏改性沥青的抗老化性能较好,但存储稳定性较差。

To overcome the defects of high viscosity modified asphalt(HVM)such as high price and high addition which may result in the high cost and workability problem,with the styrene-butadienestyrene(SBS)polymer as main component,a new methodology to produce HVM is proposed which features reactive blending of several materials conforming to composite material interface theory.Through analysis of influence of matrix asphalt,polymerization type and compound proportion of SBS modifier,solubilizer and reactive stabilizers on HVM asphalt performance,the blending ratio of different materials in the reactive compound HVM asphalt are determined;in the end,the micro morphology and reaction character are respectively analyzed by fluorescence microscope and Flourier transformation infrared spectroscopy(FTIR),and the aging performance and storage stability of reactive type SBS high viscosity modified asphalt are evaluated comprehensively.The results show that according to reactive blending technology,through the reaction and blending of linear and star SBS modifier,and activated by other materials,HVM asphalt of low cost and better performance can be produced.When the ratio of asphaltene to aromatic fraction in matrix asphalt is about 23%,the HVM asphalt may show good high temperature performance.The compound modification with the rational combination of linear type and star type SBS modifier can reduce the total dosage of SBS modifier in the reactive HVM asphalt,and the optimal proportion of SBS1301 and SBS4303 is 2∶1,meanwhile when the content of SBS composite modifier composed of SBS1301 and SBS4303 is 6.0%,and the solubilizer and reactive stabilizers is 0.1%and 5.0%respectively,the HVM asphalt can obtain the best modification effect.The micro analysis indicate that the addition of the chemical stabilizers can promote the formation of homogeneous dispersion of the SBS modifier exhibiting fine network structure,and activate the chemical reaction between SBS modifier and base asphalt as well;the RTFOT and the separation test showed that the reactive type compounded SBS high-viscosity modified asphalt had better anti-aging performance but poor storage stability.