环氧沥青固化反应机理及施工控制性能研究

Study of Curing Reaction Mechanism and Construction Control Performance of Epoxy Asphalt

关键词:  环氧沥青  微观形貌  固化反应  热塑性热固性  施工控制

Key words:  epoxy asphalt  micromorphology  curing reaction  thermoplastic thermosetting  construction control  performance comparison

摘要:

采用扫描电子显微镜和荧光显微镜观察环氧沥青（N EA）的微观形貌,探索分析N EA的固化反应特性及热塑性热固性转变机理,研究最佳混合树脂（环氧树脂与固化剂的混合物）掺量N EA混合料的容留温度、容留时间和强度发展规律等施工控制性能.结果表明：37%混合树脂掺量为N EA热塑性热固性转变临界点;38%混合树脂掺量N EA形成交联网络结构,环氧树脂为连续相,表现为热固性;50%混合树脂掺量N EA形成均匀、密实的三维交联网络结构,沥青在环氧树脂中起增韧作用;N EA混合料的容留温度和容留时间控制范围较宽,在165～185℃容留温度下最长容留时间可达30h;N EA混合料具有较高的弯拉模量和变形性能,175℃容留温度下综合性能较佳;在N EA混合料未完全固化前,40℃下养生4d,其马歇尔稳定度高于50kN,达到开放交通的强度要求.

Abstract:

Scanning electron microscopy and fluorescence microscopy were applied to observe the micromorphology of new epoxy asphalt N EA with a view to analyze the curing reaction and transition mechanism between thermoplasticity and thermoset of N EA. Through this method, the construction control performance of N EA epoxy asphalt was investigated under the best mixed resin dosage condition, such as mixing holding temperature, construction control time, strength development, etc. The results showed that 37% mixed resin is the inversion amount of N EA changed from thermoplastic to thermoset of epoxy asphalt. N EA with 38% mixed resin will form cross linked network structure, epoxy resin is the continuous phase, and exhibits thermosetting properties. N EA with 50% mixed resin has formed a well distributed and dense three dimensional cross linked network structure, in which asphalt plays a good toughening role. N EA mixture exists in wide range in construction temperature and time control. The longest reserved time of the mixture was 3h at the reserved temperature of 165185℃. The mixture possesses high bending elasticity modulus and deformation performance and it has better combination property at 175℃. Before the mixture is fully solidified, the temperature and time of health maintenance are the key factors of its strength growth, the mixture is maintained at 40℃ for 4days and its Marshall stability is higher than 50kN, to meet the requirements of open traffic.