固化剂对环氧沥青固化反应动力学的影响研究

Effects of curing agents on the curing reaction kinetics of epoxy-asphalt

采用示差扫描量热法(DSC)研究利用癸二酸、甲基四氢苯(Me THPA)和桐油酸酐(TOA)用为固化剂时所制备的环氧沥青的固化过程,得到固化反应的表观活化能Ea、频率因子A和反应级数n等动力学参数,并计算出该环氧沥青材料的起始固化温度、固化温度和后固化温度等固化参数.研究发现:试样Ⅰ(只采用癸二酸作为固化剂)、Ⅱ(采用癸二酸和甲基四氢苯复配作为固化剂)、Ⅲ(采用癸二酸、甲基四氢苯和桐油酸酐复配作为固化剂)的反应活化能Ea分别为81.29 k J/mol、67.61 k J/mol和70.41 k J/mol,频率因子A分别为32.87×104、1.30×104和3.57×104,反应级数n分别为0.91、1.00和0.89;3种试样的开始固化温度T0分别为392.09 K、382.46 K和399.83 K,恒温固化温度Tp分别为458.60K、455.36 K和441.55 K,固化完成温度Ti分别为524.38 K、520.60 K和519.26 K,综合对比而言,试样Ⅲ更适合实际的工程应用.

To predict the curing behavior theoretically,the differential scanning calorimetry（ DSC） method was used to investigate the curing process of epoxy-asphalts which were prepared by sebacic acid,methyltetrahydrophthalic anhydride（ Me THPA） and tung oil anhydride（ TOA） as curing agents. The apparent activation energy Ea,the pre-exponential factor A,the cure reaction order n,the proper gelling temperature（ T0）,curing temperature（ Tp） and treating temperature（ Ti） were calculated by Kissinger,Crane equations and extrapolating T-β method. The results showed that： the Eaof sample Ⅰ（ using sebacic acid only as curing agent）,sampleⅡ（ using sebacic acid ＋ Me THPA as compounding curing agent）,sample Ⅲ（ using sebacic acid ＋ Me THPA ＋ TOA as compounding curing agent） were 81. 29 k J / mol,67. 61 k J / mol and 70. 41 k J /mol,the A were 32. 87 × 10^4,1. 30 × 10^4 and 3. 57 × 10^4,the n were 0. 91,1. 00 and 0. 89,the T0were392. 09,382. 46 and 399. 83 K,the Tpwere 458. 60 K,455. 36 K and 441. 55 K,the Tiwere 524. 38 K,520. 60 K and 519. 26 K. Comparing the three samples,it could be found that the sample Ⅲ was more suitable for practical engineering applications.