氯化聚乙烯改性沥青热性能的研究

文章应用四组分分析法、热重分析法（TGA）和示差量热扫描法（DSC）对氯化聚乙烯改性沥青PMB-CPE的热性能进行了研究。结果发现，PMB-CPE中沥青的组分含量发生了变化，饱和分和芳香分减少，胶质和沥青质含量增加；PMB-CPE在起始热分解阶段的失重速率降低，热稳定性提高；PMB-CPE的吸热焓减少，对温度的敏感性降低。     

丁苯橡胶改性石油沥青及其油毡的研制

以丁苯橡胶(SBR)为主改性剂,聚烯烃等其它调节剂为辅助剂,在特定的工艺下对石油沥青进行改性.改性后沥青的软化点升高.针入度和延伸度增大,改善了温度敏感性.SBR改性沥青油毡,耐热度可达90℃以上,低温柔性可达-15℃(比传统纸胎油毡明显地提高了耐高温性能和耐低温性能).SBR改性沥青卷材的原材料来源充足,价格比较便宜,是改性沥青防水卷材新品种,有着良好的应用前景和明显的经济效益和社会效益.     

PPA对改性沥青及其混合料低温性能影响

分别通过弯曲梁流变试验(BBR)和半圆弯拉试验(SCB)分析多聚磷酸(PPA)对改性沥青/沥青混合料低温性能的影响。结果表明:PPA的加入改善了基质沥青及其混合料的低温性能,掺量宜为0.8%~1.6%;0.4%掺量PPA对TB复合SBS改性沥青及其混合料的低温有较好的改善效果;PPA对于沥青低温性能的提升能力随着温度降低更为显著,不同类型的PPA改性沥青的低温性能主要受蠕变速率控制;低温连续分级温度T和SCB试验G_f值、J_C值高度相关,可相互印证沥青与混合料的低温性能。     

温度对PPA改性沥青高温性能之影响研究

多聚磷酸(PPA)是改善沥青材料性能的手段之一。国内外主要采用PG分级指标或PG指标与针入度分级指标相结合的方式研究PPA添加量、PPA等级对改性沥青性质的影响。温度对PPA改性沥青性质变化规律的文献比较少。在140~240℃温度范围内采用两个剂量研究PPA对高温性能包括软化点、60℃、135℃的影响,研究发现:在不同的温度区间,改性沥青高温性能对温度的响应不同,在180~220℃之间改性沥青性质不稳定,推荐改性温度在140~160℃之间;与基质沥青相比,PPA改性可以显著提高沥青材料的高温抗永久变形阻力,PPA添加量越高高温性能改善越显著。     

PB含量对SBS与PB复配改性沥青性能的影响

为改善SBS改性沥青的使用性能,向基质沥青中添加不同比例的SBS(苯乙烯-丁二烯-苯乙烯嵌段共聚物)和PB(聚丁二烯)制备改性沥青。通过分析改性沥青的三项指标、相容性、存储稳定性、微观结构等性能,考察PB含量对改性沥青性能的影响。结果表明,向SBS中添加少量PB对改性沥青高温性能和低温性能的改善均是有利的。     

高聚物化学网构改性沥青性能的时间特征

在一定时间范围及温度条件下,一般的物理改性沥青(不包括已发生离析情况)性能基本不随时间而变化.高聚物化学网构改性沥青的性能则与时间关系有一条明显的变化曲线;在应用过程中可根据使用要求选取不同时间段的性能.     

知识园地

1　改性沥青常用术语解释1 .1　基质沥青用于生产改性沥青 ,掺加改性剂进行改性的基础沥青。1 .2　改性剂在沥青或沥青混合料中加入天然或人工的有机或无机材料 ,可熔融或分散在沥青中 ,以改善或提高沥青的路用性能的材料称为改性剂。1 .3　改性剂量改性剂在改性沥青 (包括基质沥青与改性沥青 )中的质量百分数。1 .4　改性沥青基质沥青与一种或数种改性剂通过适宜的加工工艺形成的混合物。1 .5　结合料在沥青混合料中 ,把集料粘合在一起的胶结料 ,包括各类沥青和改性沥青。1 .6　改性沥青混合料由改性沥青 (或由改性剂、基质沥青 )与矿料按…     

苯乙烯-丁二烯-苯乙烯嵌段共聚物粒径对改性沥青性能的影响

以LG 501 S型苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)为改性剂,中海油生产的36-1 70~#沥青为基质沥青,考察了改性剂粒径对改性沥青性能的影响,分析了不同粒径改性剂在沥青中的形态特征。结果表明:在相同改性剂用量下,随着改性剂粒径的减小,改善了SBS在沥青中的溶胀及分散程度,缩短了改性沥青的改性时间;在改性剂粒径为250μm时,改性沥青的软化点、延度(5℃)、黏度(135℃)依次为76℃,35.6 cm,1 860 mPa·s,均达最大值,在相同测试温度下,当改性剂粒径为250μm时,改性沥青的高温抗车辙能力最优,最高使用温度为70℃;当改性剂粒径为180μm时,改性沥青的低温抗裂性能最优,最低使用温度为-18℃;与未粉碎的改性剂相比,粉碎后改性剂的粒径明显减小,且随着改性剂粒径的降低,小粒径改性剂在粉碎后改性剂中的质量分数减小,且在沥青改性中随着发育时间的延长,改性剂在沥青中的粒径减小,体积分数增大。     

废橡胶粉改性沥青配方与工艺条件研究

以辽河AH-70沥青为基质，废胶粉为改性剂，糠醛抽出油为助剂，合成出了各项性能达到美国废旧轮胎胶粉改性沥青标准FHWA-SA-92-002的改性沥青。研究了工艺条件及胶粉用量对改性沥青性能的影响。改性后，沥青的高温稳定性、低温抗疲劳性能和抗裂性能均获得明显改善。最佳工艺条件：混合温度170-180℃，剪切速率7000r／min，剪切时间30min。改性沥青配方(质量份)：基质沥青100；活化胶粉10-20；糠醛抽出油适量。     

基于线性振幅扫描试验的沥青胶结料疲劳性能研究

为准确评价沥青胶结料疲劳特性,采用线性振幅扫描(LAS)试验测试了3种基质沥青和2种SBS改性沥青的疲劳参数,并与疲劳因子进行了比较。结果表明,随着测试温度的升高,沥青胶结料抗疲劳性能增强;基质沥青和改性沥青在疲劳性能上存在较大差异,基质沥青的疲劳因子和疲劳失败温度均高于改性沥青,而改性沥青在线性振幅扫描过程中能够在达到峰值剪切应力后,维持一段时间的高应力状态再下降,并且其疲劳寿命均大于基质沥青;不同的测试方法对于改性沥青疲劳性能评价结果的一致性较好,而基质沥青疲劳性能排序受到测试方法的影响。     

Rheological behavior of recycled polyethylene modified bitumens

Polymer modified bitumens were obtained by the introduction of recycled polyethylene into bitumens of different grades and studied by viscometry, oscillatory shear test and optical microscopy. It was shown that when recycled polyethylene was added into bitumen, the plasticity interval of bitumen increased and rheological behavior changed. The rheological behavior of polymer modified bitumen depended on the viscosity of neat bitumen and polymer concentration. The critical concentration of recycled polyethylene, at which the formation of co-continuous structure in polymer modified bitumen occurred, was revealed. Based on the rheological behavior and structure of polymer modified bitumens the conclusion was made that the field of application of polymer modified bitumens would depend on the polymer concentration.     

Plastic properties and structure of bitumen modified by recycled polyethylene

The study of the plastic properties and structure of bitumen modified by recycled polyethylene was made. It was shown that when recycled polyethylene was introduced into bitumen, the plasticity interval and viscosity of bitumen increased significantly. It was shown that the compatibility of bitumen and recycled polyethylene depends on the bulk properties of the polymer used. Two mechanisms of the modifying action of recycled polyethylenes were revealed.     

国产改性沥青碎石玛蹄脂的路用性能

提出了茂名ＡＨ—７０沥青用聚乙烯改性制备沥青碎石玛蹄脂ＳＭＡ。试验结果表明沥青和ＳＭＡ的材料性质、力学强度、热稳性、水稳性和抗车辙性能良好，达到高标准的路面技术要求，能满足南方湿热区修建高等级道路工程的需要。     

内蒙古油砂抽提沥青的实验研究

进行了热碱水抽提内蒙古油砂中沥青的实验研究。结果表明,最佳抽提条件为：碱液浓度0．3％,抽提温度90℃,碱液／油砂质量比1．5～2．0,搅拌速度75～100r／min,抽提时间20min。在抽提得到的粗沥青中加入质量分数为20％的石油醚（馏程60—90℃）,于45℃下进行了进一步的脱砂处理。结果表明,砂粒与沥青基本分离,所得沥青中沥青质的质量分数达43．40％。     

Effect of the addition of oligo ester on the rheological properties of bitumen grade 80–100

Many problems have emerged in road construction due to insufficient adhesion and elasticity of asphalt layers as road surface. Adding polymer to bitumen can improve and modify asphalt properties. Oligo ester can be used as an additive to improve bitumen properties. Through reaction of recycled polyethylene terephthalate with dipropyleneglycol, oligo ester was produced during the glycolysis process. In this research, oligo ester was fabricated through glycolysis reaction. Then it was added to the bitumen grade 80–100 in 2 and 5 wt%. The end product was evaluated by standard test methods for ductility, softening point, penetration, and thermal behavior was measured by Thermal Gravimetric, Differential Thermal Gravimetric, and Differential Thermal Analysis. The results revealed that the addition of the above polymers to bitumen reduced penetration property and increased softening point and ductility. Also, thermal behavior of bitumen was modified.     

Evaluating the effect of waste material on viscoelastic characteristics of bitumen

In this research, adding waste plastics (LDPE) and crumb rubber to bitumen causes the improvement in the viscoelastic behavior of bitumen. The sample containing 3% waste LDPE and 3% CR is the optimum one, which can be resulted from the complex modulus and the phase difference results. In continuance, elastic recovery test at 25 °C was performed on samples, and it was seen that with increase of crumb rubber content, elastic recovery increases because of elastic property of crumb rubber. In sample containing 5% waste polyethylene and 3% crumb rubber elastic recovery has been approached to the desirable amounts according to existence of enough crumb rubber. Finally, for evaluation of bitumen performance in mixture with modifiers, rotational viscosity on samples was performed.     

硬质道路石油沥青关键组分的研制

筛选出适合制备硬质道路石油沥青关键组分的减压渣油，并以此为原料，考察了蒸馏深拔、深度氧化及溶剂脱沥青工艺制备的硬质道路沥青关键组分的性能。所制备的关键组分能够大幅提升基质沥青的高温性能，且通用性好；将关键组分与基质沥青按适合比例调合可以稳定生产高温性能好的硬质道路石油沥青，其混合料耐高温性能好。同时,为便于硬质沥青关键组分的使用,还开发了关键组分的造粒成型技术,提出其适于成型造粒的黏度范围为0.6～6 Pa?S。采用关键组分生产的硬质道路沥青用于高速公路实体工程，经过2年以上的气候和通车考验，沥青路面无车辙、无开裂，保持优良的使用性能。     

Prediction of density and viscosity of bitumen

Abstract

It is well known fact that temperature and pressure significantly affects density and viscosity of bitumen. The present work utilizes Gene Expression Programming (GEP) approach to develop models to predict density and viscosity of bitumen. To evaluate the accuracy of proposed GEP based models, results reported by various researchers were utilized. This includes test results regarding Athabasca, Cold Lake and Gas free bitumen. The developed GEP based models were compared with the conventional empirical regression equations. The statistical analysis indicates that GEP based models work better than other existing models for density and viscosity of bitumen.     

不同粘度等级的再生剂对老化沥青再生性能的影响

研究了不同粘度等级的再生剂对老化沥青再生性能的影响。结果表明,不同粘度等级的再生剂对老化沥青的再生效果有明显差异。粘度低的再生剂对老化沥青软化点的降低、延度的提高、针入度的增大和粘度的减小更为明显。然而,对于轻度老化沥青,低粘度再生剂使其软化点和粘度降低幅度较大,对再生沥青的高温性能影响明显,因此轻度老化沥青宜选用粘度较高的再生剂,而重度老化沥青应选用低粘度的再生剂。