کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1467145 | 990090 | 2010 | 7 صفحه PDF | دانلود رایگان |

The glass transition temperature (Tg) and conversion (α) were measured for a cycloaliphatic epoxy/anhydride system incorporated with different contents of hydrophobic fumed silica. Samples isothermally cured at varying cure temperatures and times were analyzed by differential scanning calorimetry (DSC). Tgvs. ln(time) data at an arbitrary reference temperature were superposed by time–temperature shifts to form a master curve for the kinetically controlled reaction, and the shift factors were used to calculate an Arrhenius activation energy. Influence of the hydrophobic fumed silica was investigated from Tg and α data. For low conversions, the incorporated fumed silica may reduce segmental mobility, giving rise to an increase in Tg. For high conversions, there was a significant depression of Tg which may be associated with the presence of residual hydroxyl groups on the surface of hydrophobic fumed silica. The positive and negative effects of the fumed silica on Tg and α are discussed.
Journal: Composites Part A: Applied Science and Manufacturing - Volume 41, Issue 4, April 2010, Pages 473–479