THE MICROWAVE REACTION OF PHENYL GLYCIDYL ETHER WITH ANILINE ON INORGANIC SUPPORTS - A MODEL FOR THE MICROWAVE CROSS-LINKING OF EPOXY-RESINS

The microwave reaction between equivalent amounts of phenyl glycidyl e ther and aniline is studied on solid inorganic supports in 'dry media' , as a model for the crosslinking reaction of epoxy resins, to determi ne any chemical peculiarities due to the use of microwave energy. The resulting products are compared with standards given by the convention al heating reaction. The nature of the support is a major parameter. W ith or without microwaves, clays or silica gel (and especially clays w ith lamellar structures, such as montmorillonite K10 or Tonsil BW3) pr ovide epoxy conversion extents higher than aluminas, owing to their in creased acidic properties. Besides the epoxy-amine addition products, etherification products of the phenyl glycidyl ether are formed by bot h hydroxyl-epoxy and epoxy-epoxy competitive reactions. When compared to conventional heating, microwaves do not qualitatively change the re action products, but quantitatively modify their proportions, because both microwaves and the structure of the inorganic supports influence the relative kinetics of the different reaction paths. Copyright (C) 1 996 Elsevier Science Ltd.