IMPROVED PROCEDURES FOR THE DETERMINATION OF Tg BY DYNAMIC MECHANICAL ANALYSIS
نویسندگان
چکیده
Dynamic Mechanical Analysis (DMA) is widely used for the measurement of Tg in composite materials. However, well-known thermal lag effects can result in incorrect reporting of the data and high variability between data obtained at different test sites. Reducing the scanning rate is not sufficient to remove the effect (especially for curing systems). An improved method for compensating for this effect is presented, aided by the development of a temperature reference specimen. The new procedure developed shows good repeatability. Based on this research, a new draft standard has been developed for Tg determination by DMA (ISO/CD 6721:11).
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تاریخ انتشار 2009