Microwave curing of epoxy resins with diaminodiphenylmethane—IV. Average electrical power and pulse length dependence in pulsed irradiation

✍ Scribed by Nadir Beldjoudi; Albert Gourdenne

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 347 KB
• Volume: 24
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(88)90220-0

✦ Synopsis

A~tract--Pulse length dependence of the efficiency of the activation of curing reactions of epoxydiaminodiphenylmethane resins by pulsed microwaves (2.45 GHz) is studied at three pulse periods (1, 5 and 42 msec) or frequencies (1000, 200 and 23.8 Hz) previously revealed for a pulse length (r)/pulse period (~'-) ratio of 1/5, which lead to the fastest heating of the resins. The variations of z at given period and higher values of z/J-show that there is a r value for which the heating process is also optimized. On the other hand, at smaller ratios, the reactions are less activated than in the case of continuous mode. These results are discussed in terms of energy exchanges between waves and samples by resorting to the double relaxation process which associates dipolar and segmental relaxations.