苯酚介质中双酚A缩水甘油醚/乙二胺环氧树脂降解工艺与动力学研究

Degradation Technology and Kinetics of DGEBA/EDA Epoxy Resin in Phenol

以苯酚为反应介质，在温度280～340℃、时间30—300min条件下，研究了双酚A缩水甘油醚／乙二胺（DGEBA／EDA）环氧树脂的降解反应，考察了温度、时间等因素对降解的影响。通过气相色谱．质谱联用（GC—MS）和高效液相色谱（HPLC）对液相产物进行了定性和定量分析。结果表明：降解产物为40余种C3-C20有机化合物，相对分子量为93—318，主要组分是苯酚、对异丙基苯酚、双酚A及少量酚类化合物和含氧基团有机物等；温度越高，时阃越长，降解程度越大，主要单体收率越高。340℃，70min时，主产物对异丙基苯酚和双酚A的收率总量最大，分别为25．9％和28．1％。根据反应体系压力随时间的变化曲线初步推断探讨了降解反应的机理，通过实验数据关联，得出降解反应级数为一级，降解反应活化能为100．3kJ．mol-1，对比可知双酚A缩水甘油醚／乙二胺环氧树脂在有机相苯酚中的降解能够降低其反应活化能。最后得到降解反应速率方程为～d[ER]／dt-=4．5×10^7exp（-1．0×10^5／R／3【ER】。

Degradation of DGEBA/EDA epoxy resin was carried out in a batch reactor at 280-340℃, for 30-300 min in order to study its feature of degradation in phenol medium. Liquid products were analyzed by gas chromatography-mass spectrometer （GC-MS） and high performance liquid chromatography （HPLC） qualitatively and quantitatively. More than 40 organic compounds from Cs to C20 were identified in the liquid product. The main reaction products are phenol, p-isopropyiphenol, bisphenol A, some phenolic compounds and organic matter containing oxygen groups, etc. Degradation ratio and yields of main products increase with the increase of reaction temperature and time. It was found that the yields of main products-p-isopropylphenol and BPA can reach the maximum of 25.9% and 28.1%, respectively, under the optimal conditions as follows： at 340℃and for 70 min. The mechanism of the degradation was infered through the the time-pressure curve of the reaction system. The result of kinetic analysis shows that the degradation is a first order reaction, and the dependence of the rate constant on the reaction temperature was correlated by the Arrhenius relation, which shows that the activation energy is 100.3 kJ.mol-1. The reaction rate equation obtained is -d[ER]/dt= 4.5× 10^7 exp（-1.0× 10^5/RT） [ER].