基于废旧橡塑高分子合金的稳定型改性沥青研究

In recent years, environment was polluted seriously by numerous waste rubber and plastic result from industry,agriculture and living. Waste rubber and plastic were used to modify asphalt which could not only solve these problems, but also asphalt composite modified by reclaimed rubber and plastic had the advantage performance that rubber modified asphalt and plastic modified asphalt provided together. This modified asphalt could improve pavement's life-span and increase investment benefits. Therefore, it was very important to study the modification mechanism of stabilized asphalt composite modified by reclaimed rubber and plastic in this project. In order to research the compatibility of plastic with rubber,solubility parameters of reclaimed rubber and plastic were tested respectively in the laboratory and their main chemistry structural formulas were analyzed. If the solubility parameters of plastic and rubber were approximate, it would present a good compatibility between plastic and rubber. According to the theory of interface thermodynamics, melting heat values of plastic and plastic composed with rubber were calculated and compared by the differential scanning calorimetry (DSC). By this method, compatible degree of plastic and rubber could be analyzed. Rubber-plastic blending system was analyzed for whether or not this blending system had new substances by infrared spectra (IR). After that, stabilized asphalt composite modified by reclaimed rubber and plastic was made in the laboratory by adopting reasonable processing skills and adding suitable stabilizers and compatibilizers. The chemical compositions and performance of modified asphalt were then studied.The network of the alloy modifier/base asphalt blends was observed by atomic force microscope(AFM) and the relationship between the network of blendings and the performance of modified asphalt was analyed. A mathematical model was developed to demonstrate the relationship between the performance index of modified asphalt, performance index of base asphalt and ratios of reclaimed rubber and plastic in the modified asphalt. Through this model, the performance of modified asphalt and mixing amount of modifier could be predicted. The performance indexs of penetration classification system and performance grade (PG) classification system for modified asphalt as well as chemical group composition of modified asphalt were tested in lab. Based on the experimental result, some suitbale changes for the modified asphalt were conducted to realize the expectation aim.Road performance and mechanical property for modified asphalt mixture were tested in lab. It included Hamburg wheel tracking test, bending test at low temperature, Four-point bending flexural test and so on.The polymer alloy modified asphalt was used to pave a representative testing road and the usage information of the testing road was observed. By the experimental results, industrialized production of modified asphalt was realized.

为发挥废旧橡胶和塑料各自改性沥青的优势，有效解决环境污染，降低成本，延长道路使用寿命，开展稳定型废旧橡塑高分子合金改性沥青研究。试验测定废橡胶和塑料溶解度参数并分析废橡胶和塑料的化学结构。基于界面热力学理论，应用差示扫描量热(DSC)法计算塑料与橡胶合金前后熔融吸热值，确定塑料与橡胶的相容程度，通过红外光谱分析废旧橡胶与塑料的共混反应。优化加工工艺并选择合适的相容剂和稳定剂，研制稳定型废橡塑高分子合金改性沥青材料，采用原子力显微镜分析废旧橡塑合金与基质沥青形成共混体系的空间网络结构，探究其机理。建立废旧橡塑高分子合金改性沥青性能指标与基质沥青性能指标、废旧橡胶、废旧塑料掺量关系的数学模型，测定合金改性沥青的化学族组成，利用针入度分级和PG分级体系的有关性能指标评价其性能。分析稳定型废旧橡塑高分子合金改性沥青混合料路用性能和力学性能，铺筑试验路，实现稳定型废旧橡塑高分子合金改性沥青的工业化。

为发挥废旧橡胶、塑料各自改性沥青优势，有效解决环境污染，降低成本，延长道路使用寿命，开展了稳定型废旧橡塑高分子合金改性沥青的研究。首先分析了废旧塑料和废旧橡胶的相容性，在特定的工艺条件下用双螺杆挤出机制备不同橡塑比的橡塑高分子合金改性剂（橡塑比为5:5、6:4、7:3，分别简称为A改性剂、B改性剂和C改性剂）。通过红外光谱分析和差示扫描量热分析（DSC）研究了废旧橡胶和废旧塑料的相容性机理。采用四因素三水平的正交试验以及极差分析方法确定了橡塑合金改性沥青的制备方案，研究了改性剂的最佳掺量，并探索了选用合适的稳定剂、相容剂使改性沥青稳定化。通过对合金改性沥青化学族组成的组分分析、利用原子力显微镜分析了废旧橡塑合金与基质沥青形成的共混体系的空间网络结构，并探究了其改性机理。基于针入度分级和Superpave沥青胶结料PG分级体系全面测定稳定型废旧橡塑改性沥青的高温稳定性、低温抗裂性以及疲劳性能。根据试验数据建立了稳定型废旧橡塑高分子合金改性沥青高温性能、低温性能、疲劳性能、老化性能23个路用性能指标预估数学模型，利用预估模型可以根据废旧橡胶、废旧塑料的掺量预估稳定型废旧橡塑高分子合金改性沥青的路用性能，实验证明结果可靠。对研发的稳定型废旧橡塑合金改性沥青混合料的路用性能进行了评定，并与相同级配SBS、橡胶改性沥青混合料进行了比对。采取室内试验，对稳定型废旧橡塑高分子合金改性沥青混合料的抗拉强度、抗剪强度、动态模量、疲劳性能等力学设计参数进行了研究，推荐了稳定型废旧橡塑高分子合金改性沥青混合料设计参数的取值范围，并建立了废旧橡塑高分子合金改性沥青混合料动态模量主曲线，分析了改性沥青混合料流动数与动稳定度的相关性。采用有限元法建立模型对稳定型废旧橡塑高分子合金改性沥青混合料沥青路面结构层位的适用性进行了分析。最后，结合研究成果，在京台高速公路曲阜段和山东省省道248线等实体工程中对废旧橡塑合金改性沥青技术进行了推广应用。