Synthesis of elevated-molecular-weight epoxy resins with aid of microwaves
- RAPID COMMUNICATION
Polimery 2002, No 11-12, 842
A new method of synthesis of elevated-molecular-weight (E-M) epoxy resins with desired epoxy-groups content, based on polyaddition of bisphenol A to a lower-molecular-weight (L-M) epoxy resin (epoxy value EV = 0.57 mol/l00 g) under microwave irradiation in the presence of 2-methylimidazole, as a catalyst, was described. Syntheses were carried out in a multimode microwave reactor "Plazma tronika" (Poland) of microwave frequency 2.45 GHz and maximal microwave power 300 W. Analogical syntheses have been done using conventional heating for the comparison of the methods. Values of EV, Mn, Mw and Mw/Mn of the products obtained were determined. The main advantage of the proces s is twofold reduction of reaction time of the processes carried at microwave reactors in comparison to the conventional heating.
Keywords: microwave irradiation, epoxy resins, polyaddition, reaction time