废橡胶粉增韧环氧沥青及其机理研究

引入废橡胶粉可改善道路铺装用环氧沥青材料的低温抗裂性能.考察了反应温度、废橡胶粉含量和顺酐含量对沥青性能的影响.采用正交实验确定了如下最佳工艺：反应温度为170℃,废橡胶粉含量12 g/100 g基质沥青,顺酐含量3.2 g/100 g基质沥青.制备的废橡胶粉改性环氧沥青材料在-20℃下具有1.25％的断裂延伸率,在23℃常温下具有2.12 MPa的强度和126.34％的断裂延伸率.通过Mooney-Rivlin方程对废橡胶粉改性环氧沥青应力应变曲线的分析研究表明：添加废橡胶粉改性产生了新的化学交联,导致其化学交联密度增大,同时存在物理缠结,废橡胶粉与环氧沥青固化产生了互穿网络结构,导致材料强度和韧性均明显增加.

Preparation and Mechanism of Crumb Rubber Toughened Epoxy Asphalt

The property of resistance to low - temperature cracking of the epoxy asphalt for road pavement can be effectively improved by the addition of crumb rubber. The influence of reaction temperature, crumb rubber and maleic anhydride content on its property was investigated. The optimal technique was determined by orthogonal experi- mental method as follows： reaction temperature of 170℃, addition content of 12 g crumb rubber and 3.2 g maleie an- hydride per 100 g asphalt respectively. The crumb rubber modified epoxy asphalt has rupture elongation of 1.25% at temperature -20℃, tensile strength of 2.12 MPa and rupture elongation of 126.34% at room temperature of 23℃. By analyzing the stress - strain curve of the modified epoxy asphalt using Mooney - Rivlin equation, it was shown that new chemical cross -linking was produced owing to the addition of crumb rubber, which resulted into larger cross - linking density. Moreover, there was physical enlacement. During the curing process, reaction among the crumb rubber and other compositions of epoxy asphalt produces IPN structure, which brings obvious increase of the material ten- sile strength and toughness.