Details

Autor(en) / Beteiligte

• Hubbard, Robert L.
• Michael Strain, S.
• Willemsen, Connor
• Tyler, David R.

Titel

Low temperature cure of epoxy thermosets attaining high Tg using a uniform microwave field

Ist Teil von

• Journal of applied polymer science, 2016-12, Vol.133 (47), p.n/a

Ort / Verlag

Hoboken: Blackwell Publishing Ltd

Erscheinungsjahr

2016

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ABSTRACT It is demonstrated for the first time that an epoxy thermoset resin can be cured at temperatures well below its Tg∞. This study compared the use of a uniform variable frequency microwave (VFM) field to standard oven curing at temperatures above and below Tg∞. Using Tg, tan δ, modulus, and FTIR measurements, it is shown that the reaction of BFDGE with MDA to attain a product with Tg∞ of 133 °C is achieved by VFM at temperatures from 100 to 140 °C; in contrast, the thermal cure normally requires 170 °C to attain the same Tg∞ and the same extent of cure. By following the pregel cure reaction with 13C‐NMR spectroscopy, it was determined that the lower cure temperatures of VFM cure predominately lead to chain extension and smaller amounts of crosslinking compared to the thermal cure. To explain these results, it is suggested that, after gelation, with VFM cure there is higher mobility from dipole rotations that continues the cure to completion without vitrification. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44222.