废旧胶粉改性沥青抗老化性能及效益分析

以辽河沥青为基质沥青,以废旧胶粉为改性剂,以糠醛抽出油为调合剂,可制备改性沥青。采用失重系数法、针入度比法考察2种沥青的抗老化性能。结果表明,与基质沥青相比,废旧胶粉改性沥青具有较好的抗老化性能。通过经济效益和社会效益分析,证明用废旧橡胶粉对沥青进行改性,既减少了废旧橡胶对环境的污染,又降低了改性沥青的生产成本。     

废轮胎(橡胶)热裂解回收利用的新进展

介绍了废轮胎(橡胶)热裂解回收利用所获得的政策支持。分析了废轮胎(橡胶)热裂解工艺水平的提高,如正压改微负压,采用缺氧和无氧技术等。总结了废轮胎(橡胶)在设备方面的改进与提高。     

Utilization of sulfur and crumb rubber in asphalt modification

In this study, waste crumb rubber and sulfur were utilized to enhance the performance of asphalt binder for pavement applications. About 20–50% of sulfur and 1–6% crumb rubber were used. Melt properties were investigated using thermal analysis, dynamic and steady shear rheology, and artificial aging. Rheological tests were carried out in ARES rheometer. Both steady and dynamic shear rheology showed that crumb rubber improved the viscoelastic properties of the sulfur‐extended asphalt binder. Crumb rubber modification reduced temperature susceptibility of sulfur/asphalt, and increased the upper grading (performance) temperature of sulfur asphalt. The combined effect of sulfur and crumb rubber reduced the activation energy compared with that of pure asphalt. Zero‐shear viscosity and strategic highway research program rutting parameter (G*/sinδ) improved by crumb rubber incorporation into the sulfur asphalt binder. Short‐term aging improved G*/sinδ with slight increase in activation energy. The addition of sulfur to asphalt matrix increased the viscoelastic properties (G′ and G″) of sulfur asphalt. The addition of crumb rubber to sulfur asphalt enhanced the temperature resistance of the binder. Utilization of waste crumb rubber and sulfur in asphalt modification proved to enhance asphalt pavement life. In addition, utilization of such wastes can help in meeting the extra demand for asphalt, reduce the pavement cost, and help in solving a waste disposal problem. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40046.     

Effect of ground rubber powder and devulcanizates on the properties of natural rubber compounds

Ground rubber powder (GRP) and devulcanized rubber (Dev.R) waste through a continuous shear‐flow reaction were used as fillers for virgin natural rubber. A Horikx plot and the gel fraction proved that both main‐chain scission and crosslink scission occurred during the devulcanization. The cure characteristics, swelling behavior, crosslink density, and mechanical properties were studied. GRP and Dev.R, generated from passenger car and light truck tires, showed applicable mechanical properties in the new rubber compounds, and the compounds containing Dev.R demonstrated better properties than those containing GRP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 208–217, 2005     

废旧轮胎粉碎技术及其应用进展

世界各国的废旧轮胎数量日益增加,废旧轮胎堆放不仅造成环境污染,还导致橡胶资源浪费,对废旧轮胎进行合理的回收利用已经势在必行。现阶段,粉碎废旧轮胎以制备胶粉因工艺优势而成为废旧轮胎的主要回收方式。综述国内外粉碎废旧轮胎制备胶粉技术,详细介绍干法粉碎和湿法粉碎技术及相关工艺,其中干法粉碎包括常温和低温粉碎,湿法粉碎主要包括RAPRA法、常温浸混粉碎法、全水相法和高压水射流冲击粉碎法。对主要粉碎设备及其粉碎原理进行概述。指出全水相法因制得的胶粉性能更加优异,且工艺成本低及环保性表现突出,有望成为未来废旧轮胎粉碎技术主要发展方向。     

废橡胶热裂解技术现状及发展方向

废橡胶是继白色污染之后又一大污染——黑色污染,是世界性的又一大难题,其中比重最大的就是废轮胎,世界各国尤其是发达国家纷纷致力于轮胎的回收利用研究.特别是其回收产品的再利用:一方面解决资源的短缺;另一方面获取较高的经济价值.经长期的探究,人们发现与翻新、制造胶粉和再生胶、作沥青填料、直接作为燃料焚烧等处理方法相比,热裂解...     

固体废弃物应用于橡胶的研究进展

将固体废弃物应用于橡胶制备废弃物/橡胶复合材料是资源循环、环境保护、拓展橡胶应用领域的有效方法。本文综述了多种固体废弃物在橡胶中的应用,包括工业废弃物、农业废弃物和生活废弃物,对增强废弃物与橡胶基体两相结合力所采取的多种方法以及对废弃物/橡胶复合材料应用于汽车、建筑、降噪、电磁波屏蔽、油田废水治理、食品包装等多个领域进行了归纳,指出固体废弃物在橡胶应用中存在的问题,认为在固体废弃物及橡胶基体的选择、废弃物在橡胶基体中的分散性、废弃物与橡胶基体的相容性和反应性等研究方面具有一定的挑战和广阔的发展空间。     

Surface graft copolymerization of poly(methyl methacrylate) onto waste tire rubber powder through ozonization

Grinding of tires offers a promising opportunity for recycling waste rubber because fine waste tire rubber particle may be used as fillers and property modifiers in thermoplastic, elastomer, and thermoset blends. However, due to the lack of reactive sites on the WTR surface, the adhesion between WTR powder and matrix is poor. In this article, ozonization of waste tire rubber (WTR) powder was performed to produce some “immobile” reactive points (hydroperoxide groups) on the WTR surface. The free radical generated by the decomposition of hydroperoxide groups on WTR surface, was used to initiate graft polymerization of methyl methacrylate (MMA) onto the surface of WTR powder. The experimental results showed that MMA was successfully grafted onto the surface of WTR. The hydrophilicity of the MMA grafted WTR (MMA‐g‐WTR) was improved. The concentration of hydroperoxide groups and the graft degree were both increased with ozonization time. With increasing of polymerization time and polymerization temperature, the grafting degree increased. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Investigation of new composite materials based on activated EPDM rubber waste particles by liquid polymers

Despite of the variety of existing techniques, there is still a continuous demand in the development of more efficient recycling technologies, for economic and environmental reasons. A new approach for recycling EPDM rubber waste has been recently introduced utilizing a solvent free activation process by addition of liquid polymers (LP). The present study investigates the influence of the content and varying types of activated rubber waste particles (RWP‐LP) in new composites. By varying the proportion of RWP‐LP in the range from 25 up to 75 v/v % information about optimized compositions of new compounds were obtained. It was found that the ratio and type of RWP‐LP induce significant differences in terms of cure characteristics, mechanical properties, crosslink density and morphology. Promising results with high potential application for the production of seal and sealing systems on the industrial scale were obtained by using up to 50 v/v % of RWP‐LP with low ethylene amount. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42097.     

The use of recycled elastomeric materials for sustainability in circular economy

The use of scrapped elastomeric goods primarily service failed or worn-out tires is a challenging task for the rubber society. To address this issue, recycling and reusing of these tires by different technique bring major relief toward environmental concern. Recycling technology generates secondary raw materials, which are important resources for manufacturing industries and contribute significantly for the sustainability in circular economy. In this work, an effort was made to understand the retention of physical properties as a function of crumb rubber loading and particle size. Four different sizes of cryogenically shredded crumb rubber particles (120, 140, 200, and 270 mesh) were physicochemically characterized and incorporated by 10 phr of each in two different grades of carbon black–filled, natural rubber–based tread compound. The mixed compounds were characterized and compared with the control one. Optical microscope and scanning electron microscope analyses concluded that the finer the particle size, the better is the dispersion of crumb rubber particles which provide superior mechanical, extrusion, and wear properties. Tensile properties were retained around 95%–97% for both 270-mesh loaded compounds, which indicates that reduction in particle size can increase the volume of recycled product utilization.     

废旧轮胎橡胶颗粒在沥青混合料中的应用

为了探索废旧橡胶轮胎回收再利用的新途径,研究了橡胶颗粒沥青混合料的级配及拌和、成型方法,并通过车辙实验、低温小粱弯曲实验和冻融劈裂实验等分析了橡胶颗粒沥青混合料的高低温性能和抗水损害性能等基本路用性能。论证了将废旧轮胎橡胶颗粒作为骨料应用于筑路用的沥青混合料的可行性。     

Introductory behavior of rubber concrete

This article introduces a new type of concrete, the so‐called rubber concrete, and thereupon presents a way of modification of waste rubber to construction articles. The conventional cement concrete is made by mixing cement with sand and pebbles, but the rubber concrete proposed here virtually excludes cement completely. The manufacturing process of rubber concrete can be divided into two methods, which are designated for dry and wet processes, but this article focused just on the dry process. The physical properties of rubber composite increased with the silane treatment of added aggregates, but the volume of the aggregate might not be a critical factor affecting the compressive strength in the range of the aggregate contents used in this study, that is, the interfacial adhesion between the matrix rubber and the aggregates was a key factor to improve the mechanical properties of rubber concrete. The compressive strength of rubber concrete was about 89 MPa and the Poisson's ratio, which is the ratio of compressive‐to‐tensile strength, was 5.5%. From the viewpoint of the compressive strength and the Poisson's ratio, rubber concrete had better properties than those of conventional cement concrete. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 35–40, 1999     

Improvement of mechanical properties of rubber compounds using waste rubber/virgin rubber

Ground rubber powder (GRP) and devulcanized rubber waste obtained using the process of continuous shear flow reaction were used as both fillers and a part of rubber in virgin natural rubber (NR). The cure characteristics, swelling behavior, cross‐link density, mechanical properties, and morphology were studied in our laboratory. The GRP and devulcanized rubber, which were generated from passenger car and light truck tires, showed applicable mechanical properties in new rubber compounds, and the compounds that contained devulcanized rubber showed better properties than those with GRP. In particular, devulcanized rubber as a part of rubber obtained through a cross‐link reaction exhibited excellent mechanical properties, with a strong potential for future applications. POLYM. ENG. SCI., 45:1239–1246, 2005. © 2005 Society of Plastics Engineers     

Cure characteristics and physical properties of ground‐rubber‐filled natural rubber vulcanizates: Effects of the curing systems of the ground rubber and rubber matrix

Recycling discarded rubber is important for both environmental and economic reasons. One of the most attractive methods of recycling rubber waste is to use ground rubber (GR) as a compounding ingredient or as a replacement for raw polymers. In this study, ground natural rubber was prepared with different curing systems and compounded into the parent compounds. The cure behaviors and physical properties of the GR‐filled vulcanizates were investigated, and they were largely affected by the curing systems of the rubber matrix and GR. GR‐filled vulcanizates with GR and the rubber matrix, having a conventional curing system, showed the largest changes in the cure characteristics. The greatest decrease in the physical properties was observed for peroxide‐cured‐GR‐filled vulcanizates. The addition of GR decreased the crosslink density of the GR‐filled vulcanizates. This was thought to be the main reason for the reduction of the mechanical properties of the GR‐filled vulcanizates. However, the adhesion between the GR and rubber matrix may also have caused the differences in the physical properties of the GR‐filled vulcanizates with respect to the curing systems of the rubber matrix and GR. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Structural evolution of recycled tire rubber in asphalt

The performance of recycled‐tire‐rubber‐modified asphalt mainly depends on the structure of rubber in the asphalt. The effects of the curing temperature, mixing time, and shearing on the evolution of the chemical structure and morphological structure of crumb rubber in asphalt were investigated. The crosslink density, compositions, and morphological evolution of the residual crumb rubber were characterized. The results show that the structure evolution of tire rubber in asphalt was greatly affected by the curing temperature. At a low curing temperature (180°C), the crosslinking network of the tire rubber was broken down, and this led to the partial dissolution of natural rubber (NR). However, at high curing temperature (240°C), the dissolution of NR, synthetic rubber, carbon black, and inorganic filler was observed. The released carbon black covered with a thin layer of bound rubber dispersed at a microstructured or nanostructured size in the asphalt. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42954.     

固体废弃物微波技术处理及其资源化

随着国民经济的快速发展,废旧橡胶轮胎、废旧塑料、废旧纤维素以及污泥等固体废弃物的量迅猛增加,固体废弃物的处理和资源化已迫在眉睫。在固体废弃物的处理及资源化过程中,微波技术具有加热速率快、加热均匀和固体废弃物有价值资源的选择性好等优点。采用微波技术处理废旧橡胶轮胎时,产物中的液体有机物选择性比较高,对炭黑和钢丝等物料的回收也比较简单,国外已有日均处理(6 000~7 000)条废旧轮胎的工业化生产线,可以实现废旧轮胎100%资源化再利用;在废旧塑料聚丙烯中添加石墨等微波吸收物质,然后进行微波技术处理,烯烃类组分的液体产物可以达到48.16%;废旧纤维素及其制品可以在较低温度下进行微波处理,废纸在200℃进行微波裂解可以获得15%的裂解气、42%的裂解油和43%的炭黑;含油污泥进行微波技术处理不但可获得液体有机物,还能够实现污泥的油水分离。因此,采用微波技术处理固体废弃物是一个废物的减量化、无害化和资源化过程,具有很好的应用前景。对近年来采用微波技术处理这些固体废弃物及其资源化的研究进展进行总结和评述,以期对我国固体废弃物处理和资源化的发展提供参考。     

Rubberized geopolymer composites: A comprehensive review

The construction sector has been addressing the issue of integrating sustainability into production processes over the last few years, either through solid waste materials as aggregates in concrete or the search for more eco-friendly raw materials. Besides, the global trends group focused on developing an alternative to cement, which is a significant contributor to pollution of the environment due to its greenhouse gas emissions. Geopolymer (GP) is one of the most acceptable solutions for utilizing all industrial by-products containing an alumino-silicate (A-S) source material. However, one method to recycle waste rubber tires is incorporating them into geopolymer concrete (GPC) as an alternative to natural aggregates. Recently, the potential of combining the advantages of GPC with rubberized concrete to produce rubberized geopolymer concrete (Ru-GPC) as a viable, sustainable building material has been recognized. This paper presents a state-of-the-art review of the waste rubber's environmental and economic impact, resources, recycling, classifications, and physicochemical properties. Besides, this article provides in-depth studies on the behaviors and properties of Ru-GPC composites, such as their basic components, preparation and curing processes, fresh and physical properties, mechanical properties, dynamic properties, durability properties, microstructures, and insulation properties. The effect of crumb rubber (CRu) substitution on critical properties is addressed critically. Also, it highlights the applications, embodied CO₂ emissions, and cost analysis of Ru-GPC. Moreover, gaps in the literature and recommendations for future study have been identified to support further developments in the investigation and future publication of Ru-GPC materials in practice.     

废橡胶颗粒沥青混合料级配组成的优化

应用星点设计-效应面优化法进行废橡胶颗粒沥青混合料级配组成的优化设计,运用SPSS软件分析实验结果,描绘了橡胶颗粒掺量、粗集料用量和粗橡胶颗粒用量等影响因素的效应面,建立了相应的数学模型,得到了橡胶颗粒沥青混合料的最优级配组成。结果表明,当橡胶颗粒掺量为2.0%~6.0%、粗集料用量为60.0%~75.0%、粗橡胶颗粒用量为30.0%~60.0%时,橡胶颗粒沥青混合料综合性能最优;将星点设计-效应面优化法应用于橡胶颗粒沥青混合料的级配组成优化是可行的。     

废旧轮胎/橡胶回收利用技术研究进展

近几年来,废旧轮胎/橡胶所引起的环境问题得到人们的重视,回收利用已成为我国乃至世界研究的热点。从裂解、催化裂解、轮胎原料、反应动力学以及工艺条件等方面概述了废旧轮胎/橡胶回收利用技术最新研究进展。催化裂解成为废旧轮胎/橡胶回收利用的主要方式,研究较多的催化剂主要是ZSM-5、MCM系列以及ITQ系列。     

Specific heats of rubber compounds

The specific heats of rubber compounds are very important not only for the thermodynamic calculations in various rubber processings; mixing, extrusion, calendering, and vulcanization, etc., but also for the service life of the final products under repeated stressing conditions. In this study, the specific heats of various compounding ingredients and their compounds for tires were determined using a differential scanning calorimeter (DSC) in the temperature range from 45 to 95°C. The determined specific heats, C_p, were compared with the previous published results for natural rubber (NR), styrene–butadiene rubber (SBR), polybutadiene rubber (BR), and isoprene–isobutyl rubber (IIR). The effects of carbon black loading and vulcanization on the specific heats were investigated. The measured specific heats of the compounds were compared with the calculated values based on the fractional summation of the specific heat of each compounding ingredient. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1513–1522, 1999