Storage modulus-cure time plot

Figure 5.41. Increase in storage modulus (which parallels the rise in viscosity) from the onset of reaction for a supported sample (resin coated onto an inert substrate) of an epoxy resin. Curve (a) is the isothermal storage modulus-cure time plot curve (b) shows loss modulus. The storage modulus rises in two steps, the first due to gelation and the second to vitrification, and then levels off at a high value characteristic of the glassy state. The loss modulus peak indicates the time to vitrify. High performance epoxy, cure at 155 °C (from Lee and Goldfarb, 1981a, b with permission of the Society of Plastics Engineers).

Fig. 46. DMA isothermal modulus and tan vs cure time plot for a supported epoxy resin sample (resin coated onto an inert fiber glass substrate) (a) storage modulus, (b) loss...

Figure 3. DMA results of NOA63 cured for (i) 5 min, (ii) 30 min, (iii) 1 hr, and (iv) 3 hr (a) storage modulus and (b) plots of storage modulus versus UV curing time at three different temperatures. For this DMA measurement NOA63 samples prepared in Figure 2 were used.

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