Analysis of performance and mechanism of Buton rock asphalt modified asphalt

The performance and modification mechanism of Buton rock asphalt (BRA) modified asphalt were analyzed. The road performance of modified asphalt was observed and compared with SBS modified asphalt to confirm the modification mechanism. Four-component test, and dynamic shear rheological tests were conducted to identify the performance of modified asphalt. Fourier transform infrared spectroscopy was carried out to analyze the modification mechanism of modified asphalt. Finally, the rutting, low-temperature bending beam failure, and freeze–thaw splitting tests were used to evaluate the high-temperature performance, low-temperature cracking resistance, and water stability performance of mixtures, respectively. The results show that the high-temperature performance of asphalt can be improved by BRA with asphaltene and resin increased. It is likely that there is no new functional group generated and this process was physical changes mainly. The honeycomb structure of BRA ashes/particles increased the contact area between the base asphalt and BRA ashes/particles, which makes the asphalt change from the homogeneous body into a two-phase continuous structure system. Consequently, the adhesion between asphalt and BRA ashes/particles was enhanced, and the dynamic stability, bending coefficient and splitting strength ratio were improved. It indicates that the test results of asphalt mixtures verified the modification effect of BRA. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46903.     

废旧橡胶粉改性沥青研究进展

介绍了废旧橡胶粉改性沥青的国内外应用状况,分析了胶粉改性沥青的特点、机理、方法以及胶粉改性沥青的贮存稳定性和感温性等。指出将废旧橡胶粉用于改性沥青,既能提高沥青的性能,又有利于废旧橡胶的循环利用,减少环境污染,有着良好的发展前景。提出我国应尽快制定出废旧橡胶粉改性沥青的行业标准规范。     

Rheological investigation of the influence of acrylate polymers on the modification of asphalt

The effect of ethylene, ethylene acrylate and glycidyl methacrylate (EA) terpolymer, and ethylene butyl acrylate (EBA) copolymer on asphalt modification was investigated at 4, 6 and 8% polymer concentrations. Both melt state rheology and asphalt concrete mix (ACM) were investigated. In the melt state analysis, dynamic shear rheology, storage stability, artificial ageing, and performance grading (PG) were studied. The PG grading of polymer modified asphalt (PMA) is correlated to the elastic properties of the polymers. Both resins improved the rheological properties, reduced the temperature susceptibility, showed better storage stability, and increase the upper grading (performance) temperature of the base asphalt. The two polymers showed similar ageing characteristics with little influence on flow activation energy. In asphalt concrete mix analysis, Marshall stability, stripping (durability), resilient modulus, and permanent deformation tests were performed. Polymer‐modified asphalt concrete mix (PMACM) has increased percent retained stability and the resilient modulus when compared with ACM. The elastic modulus of PMA and the resilient modulus of their ACM followed the same trend. Weak influence on water sensitivity was observed, but excellent rutting resistance was obtained for PMACM over ACM. EA (much cheaper than EBA) produced satisfactory properties of PMA and superior ACM properties when blended with the high asphaltenes Arabian asphalt. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3446–3456, 2006     

改性沥青中SBS含量检测方法的研究

快速准确的测定改性沥青中SBS含量对控制工程质量至关重要,本文通过实验研究确定了一种快速可靠测定SBS含量的方法。通过该方法对SBS含量为4%、5%、6%的改性沥青含量进行检测。结果表明：该方法所得检测结果误差不超过2%,实验数据的精密度满足工程以及相关标准要求。     

Outdoor aging of road asphalt and SBS modified asphalt

The process of performance degradation of road asphalt (RA) is regarded as aging. At present, better understanding of the thermal-oxidative aging of asphalt is achieved and the corresponding method to evaluate this process is developed; meanwhile, photo-oxidative aging (aging in an atmospheric environment, which is referred to as “outdoor aging” in this paper) of asphalt remains at the initial stages of scientific exploration. The outdoor natural ultraviolet (UV) aging of RA and SBS modified asphalt (SBSMA) are investigated in this study. The experimental results show that the basic performances of RA and SBSMA present similar change tendencies. The softening point increased, while the penetration and ductility decreased as the outdoor aging time passed by, and the 5°C ductility (ductility measured at 5°C) of SBSMA decreased very quickly. The group components of RA and SBSMA also change during UV aging. The content of asphaltene rose and that of aromatics and saturates decreased, while the content of resins changed insignificantly. Moreover, the Fourier transform infrared (FTIR) graphs show that the content of sulfoxide and carbonyl groups in RA and SBSMA increased significantly during the outdoor aging process.     

Extraction of proteins and polymers using reverse micelles and percolation process

Specific interfacial properties, which affect protein extraction in AOT and AOT-lecithin reverse micellar systems (RVMS), have been studied by using their percolation processes. Solubilization of proteins or synthetic polymers into RVMS by the injection method and its effect on the percolation processes could be easily evaluated by the measurement of electrical conductivity. The percolation process is found to be a sensitive and convenient measure of micro-interface of RVMS solubilizing various polymers or proteins, which clearly reflects the polymer(protein)-micellar and micellar-micellar interactions. The stability of RVMS or micellar-micellar interaction was dependent on the kinds, concentration and molecular weight of solubilized polymers. The value of p, defined as the variation of percolation threshold with the concentration of solubilized polymers, can be utilized to evaluate the stability of RVMS solubilizing polymers or micellar-micellar interactions. The values of Β are affected by the hydrophobicity, molecular weight and absolute value of the net charge of the polymers solubilized into the AOT reverse micelles, which were evaluated by using Aqueous Two-Phase Systems (ATPS).     

改性沥青汽车底盘胶的研究

以石油沥青为基料,丁基橡胶为改性剂,松香树脂为增粘剂,石棉粉为填料,合成了一种汽车底盘 用改性沥青胶粘剂。研究了各组分用量对胶粘剂粘接性能的影响,结果表明当丁基橡胶的加入量为10％,增 粘剂加入量为10％,填料的加入量为15％,混合溶剂适量时,综合效果最佳。该胶粘剂有较好的粘接性、机械 性能和耐高温性能。     

EPDM改性沥青研究

采用母体法制备改性沥青，研究了三元乙丙橡胶（EPDM）改性茂名90^#沥青，通过改变EPDM用量，薄膜烘箱老化（TFOT）和动态力学分析等方法，并与SBR改性沥青比较，考察了EPDM改性沥青的基本性能，结果发现，EPDM改性后沥青的感温性明显下降，耐老化性，低温抗裂性和高温热稳定性提高，但贮存稳定性差。     

胶粉改性沥青的流变特性及改性机理

研究了胶粉改性沥青(CRMA)母料的流变特性,考察了混合时间及混合温度对CRMA母料流变特性的影响,提出并验证了胶粉对沥青改性的"力化学"机理。结果表明,与基质沥青相比,CRMA母料的表观黏度较高,黏流活化能与非牛顿指数较低,加入胶粉显著降低了沥青流变特性对剪切速率和温度变化的敏感性;提高混合温度与延长混合时间对CRMA母料流变特性的影响较大,最佳的混合时间为2h;胶粉与沥青混合过程中,混合体系的温度和胶粉的降解度随着混合时间的延长而增大,且在混合时间为2h时,80%以上的胶粉已发生降解;改性机理符合"力化学"原理。     

Study of long-term skid and wear resistance of waterborne epoxy resin-SBR compound modified emulsified asphalt microsurfacing

As an eco-friendly technology for pavement preventive maintenance, microsurfacing (MS) has the potential properties of cost-saving and excellent performance benefits in repairing distress. MS also improves the surface function, especially skid resistance, of old pavements that have gradually decayed under the coupled effects of long-term environment and loads. Reasonable assessments of the long-term skid and wear resistance of the MS can provide support for accurate decision-making on preventive maintenance, which in turn reduces maintenance costs and saves maintenance costs, and ensures traffic safety. To evaluate the long-term skid and wear resistance of MS in different natural and traffic environments, this paper investigated the change of British pendulum number (BPN), rutting depth, and mass loss rate of waterborne epoxy resin-SBR compound emulsified asphalt micro-surfacing (WER-SBR MEAMS) under different environmental factors and traffic conditions based on the self-developed accelerated loading abrasion instrument. The factors considered in the experiment include temperature, rainfall, UV radiation, speed, and load. The results showed that temperature and vehicle speed had a detrimental effect on the durability of WER-SBR MEAMS, which was more pronounced after 10,000 wear loading cycles. Reducing immersion time and slowing down the aging rate can improve the durability of WER-SBR MEAMS. Further, the influence degrees of different factors on the skid and wear resistance of MS were evaluated using the gray correlation method. From the results of the gray correlation analysis, the correlation coefficients between external variables and BPN, rutting depth, and mass loss rate are all greater than 0.8, which indicate that all the variables involved have relatively obvious and regular effects on the skid and wear resistance of WER-SBR MEAMS.     

Temperature and time dependence of conductive network formation: Dynamic percolation and percolation time

Temperature and time dependence of conductive network formation in vapor-grown carbon fiber (VGCF) filled high-density polyethylene (HDPE)/poly(methyl methacrylate) (PMMA), VGCF and ketjenblack (KB) filled HDPE/isotactic polypropylene (iPP) blends have been investigated. It is found that the filled conductive polymer composites are thermodynamically non-equilibrium systems, in which the conductive network formation is temperature and time dependent, a concept named as dynamic percolation is proposed. When the composites are annealed at a temperature above the melt point of polymer matrix, the dynamic process of conductive network formation can be monitored in a real time way. Such an in situ characterization method provides more interesting information about the dispersion of conductive particles in the polymer matrix. Furthermore, a thermodynamic percolation model is modified to predict the percolation time for VGCF and KB filled HDPE/iPP multi-phase systems during the annealing treatment, and it expresses experimental results well.     

交联SBR改性沥青的研究

研究了SBR用量和交联对SBR改性沥青的性能与结构的影响。结果表明 ,随着SBR用量的增大 ,改性沥青高温时的粘度、软化点和弹性恢复率均增大 ;SBR经交联后 ,SBR改性沥青的软化点、弹性恢复率和粘韧性均增大 ;SBR改性沥青低温时的延度接近SBS改性沥青的水平 ;交联后虽使改性沥青高温时的粘度增大 ,但不会对施工造成困难 ;化学交联并不影响SBR在沥青中的分散 ,不会使SBR在沥青中聚结。     

橡胶反应共混改性沥青的机理

以混入沥青前后的共混物硫化胶模拟反应共混改性沥青,对橡胶／硫化剂／沥青、橡胶／硫化剂2种共混物硫化胶进行了以甲苯为溶剂的抽提,并对抽提物进行了元素分析和红外光谱分析。结果表明,橡胶／硫化剂／沥青共混物硫化胶的抽提物仍呈黑色,其质量保留率小于橡胶／硫化剂共混物硫化胶。SBR／硫化剂／沥青共混物硫化胶的抽提物H／C值小于SBR／硫化剂共混物硫化胶,并且小于纯沥青;且含有沥青组分所特有的N原子。l376cm^-1的甲基对称弯曲振动特征吸收峰可作为共混物硫化胶的抽提物是否存在沥青的依据。含沥青共混物硫化胶中,沥青特别是沥青质与树脂组分参与了橡胶的交联反应。     

POE弹性体改性沥青的结构与性能

研究了聚烯烃弹性体（POE）改性沥青的结构和性能,考察了POE用量对两种基质沥青常规性能的影响,并用光学显微镜观察了POE在沥青中的分布状态。结果表明,随着POE用量增加,沥青的软化点增加,25℃针入度减小,高温性能变好。通过储存稳定性实验发现,POE改性沥青后稳定性较差。POE改性沥青相结构研究发现,随着POE用量的增加,POE由分散相变为连续相,POE质量分数为6%时,基质沥青发生相转变。     

基于GPC法的改性沥青SBS含量测试方法研究

采用GPC对不同SBS剂量的改性沥青进行了测试,建立了SBS剂量与GPC测试数值的关系,并采用已知SBS剂量的样品对该方法进行验证。结果显示,GPC测得的SBS含量与SBS真实剂量线性关系良好,SBS剂量相对偏差均在5%以内,表明GPC法是一种检测改性沥青质量的快速、可靠的测试方法。     

CPE系列聚合物改性路用沥青

研究了氯化聚乙烯(CPE)系列聚合物体系对改性沥青性能的影响．以及CPE含量、母料比例等对改性沥青的影响。实验结果表明．母炼胶法制备的改性沥青能够取得较好的效果。通过对CPE体系和CPE—g—MAH体系的比较．能直观的看到界面相容性对改性沥青起着至关重要的作用，使改性沥青呈现较好的延度、针入度和软化点。同时。对改性沥青的工艺进行了探索。     

Rheology and microstructure of functionalized polymer‐modified asphalt

Viscoelastic and morphological properties of functionalized‐polymer‐modified asphalt, FPMA, have been described as function of number of epoxy groups presented in the functionalized polymer. At low temperatures, simple viscoelastic models can predict the elastic response of FPMA at short times and its viscous behavior at long times. The increase of epoxy groups yielded an increase on activation energy for viscous deformation of FPMA, and so, on its resistance to irreversible deformations under strain cycles. From ambient to higher temperatures, emulsion model can predict rheological properties of FPMA because they behave as viscoelastic emulsions. Modification of relaxation spectrum for FPMA due to the presence of a polymer network was not as strong as in normal PMA, thus, the rheological behavior of FPMA was found similar to systems having weak networks. However, the network became stronger as the number of epoxy groups was increased. This trend was verified by morphology of FPMA. Emulsion‐like structure was observed for all FPMA but differentiating each other by the polymer particle size. It was also observed that increase on epoxy groups, polymer particle size in the FPMA decreased, and higher stability at 180°C of FPMA was observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

SBS改性沥青的结构与性能

通过动态黏弹性能、结构分析和沥青基本性能测试研究了SBS和沥青之间的相容性,以及SBS用量对改性沥青的结构与性能的影响。结果表明,SBS与沥青有一定的相容性,沥青中的某些组分可进入SBS的聚丁二烯(PB)链段区域。使PB的玻璃化转变温度升高,在高剪切力作用下也可进入聚苯乙烯(PS)链段,降低了PS的玻璃化转变温度,但不会使PS物理交联点发生严重解体。当SBS质量分数为5％时,SBS在沥青中呈彼此分离的球状颗粒;当SBS质量分数达到7％或以上时,则形成连续相。随着SBS质量分数的增加。改性沥青的软化点和低温延度升高,针入度和高温贮存稳定性下降。     

Investigation on compatibility and microstructure of PCBs‐modified asphalt

Due to the increasing production of waste Printed Circuit Boards (PCBs), there is a strong need to investigate the effective method how to recycle PCBs for protecting the environment. In this study, the PCBs were added to asphalt for preparing the PCBs‐modified asphalt to improve the performance of asphalt. The influences of PCBs on Cole‐Cole plots, segregation index, ratio difference number, and microstructure of modified asphalt were evaluated by storage stability tests, dynamic shear rheometer tests, fluorescence microscopy analysis, and fourier‐transform infrared spectroscopy analysis, respectively. The results show that addition of PCBs can improve rheological properties of asphalt and the PCBs content has significant influence on the compatibility and microstructure of modified asphalt. The optimum content of PCBs is no more than 10 wt % for the better compatibility and storage stability of PCBs‐modified asphalt. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44798.     

脱硫胶粉在乳化改性沥青中的应用

考察了不同规格胶粉及不同脱硫程度的脱硫胶粉对橡胶改性乳化沥青性能的影响,结果表明,采用100目胶粉即可制备出橡胶改性乳化沥青,但乳化沥青的性能较差;采用活化度为50%左右的100目脱硫胶粉制备乳化沥青时,脱硫胶粉的用量相比于胶粉可大幅提高;在通过外掺100目50%左右活化度的脱硫胶粉(质量分数15%,以沥青计,下同)和质量分数2%的苯乙烯-丁二烯-苯乙烯嵌段共聚物改性的乳化沥青中添加质量分数1%的丁苯胶乳,所制备橡胶改性乳化沥青无筛上剩余物,5 d储存稳定性为2.9%,蒸发残留物的25℃针入度、软化点和5℃延度分别为55 (0.1 mm)、64.5℃和22.5 cm,能够满足乳化改性沥青的技术指标要求。