环氧树脂醇解回收再制备固化动力学研究

Research on Alcoholysis Recovery, Re-Preparation, andCuring Kinetics of Epoxy Resin

针对利用环氧树脂醇解产物制备新树脂固化工艺缺乏分析的问题,首先运用非等温差示扫描量热法,研究了醇解产物含量对再制备树脂固化行为的影响。随后通过固化动力学模型,确定了再制备树脂的固化条件,并以此制备得到新树脂,测量了其介电性能。结果表明:当醇解产物替代双酚A二缩水甘油醚质量分数为25%时,再制备树脂的预固化温度小于120℃,后固化温度为160.57℃,这是因为,醇解产物中的羟基可促进环氧基的开环反应,使得再制备树脂的固化温度随醇解产物含量增加而降低;再制备树脂符合自催化双参数固化动力学模型,总反应级数大于1,且固化过程中的表观活化能Ea是固化程度α的函数,基于Ea(α)函数得到试样实际固化程度接近理论值;与原始环氧树脂相比,再制备树脂的相对介电常数、介质损耗和击穿电场强度有所增加,其介电性能满足电工用环氧树脂使用要求。该研究内容为醇解回收再制备环氧树脂的固化工艺提供了经验和指导。

This study aims to fill the analysis gap regarding the curing process of new resin made from epoxy resin alcoholysis products.Initially,a non-isothermal differential scanning calorimetry method is employed to investigate the influence of alcoholysis product content on the curing behavior of the re-prepared resin.Subsequently,the curing conditions for the re-prepared resin are determined using a curing kinetics model.A new resin is synthesized accordingly,with its dielectric properties measured.The results indicate that substituting 25%bisphenol A diglycidyl ether with alcoholysis products leads to a pre-curing temperature of the re-prepared resin below 120℃and a final curing temperature of 160.57℃.This is attributed to that the hydroxyl groups in the alcoholysis products facilitate the ring-opening reaction of epoxy groups.Consequently,as the alcoholysis products increase,the curing temperature of the re-prepared resin decreases.The re-prepared resin conforms to a self-catalytic dual-parameter curing kinetics model,with a total reaction order exceeding 1.The apparent activation energy E a during the curing process is a function of the curing degreeα,and the actual curing degree of the samples obtained from the E a(α)function closely matches theoretical values.Compared to the original epoxy resin,the re-prepared resin exhibits an increase in relative dielectric constant,dielectric loss,and breakdown strength,demonstrating the dielectric performance meeting the requirements for epoxy resins employed in power systems.This study offers valuable insights and guidance to the curing process of epoxy resin re-prepared from alcoholysis recovery.