Dynamic Mechanical Analysis part 6 pdf

... Polymer Science, 2nd ed., Wiley, New York, 19 96. L. Nielsen et al., Mechanical Properties of Polymers and Composites, Marcel-Dekker, New York, 19 96. J. Ferry, Viscoelastic Properties of Polymers, ... was not investigated. 24 Johari and colleagues have reported in both mechanical 25 and dielectric studies 26 that both the b and g transitions in bisphenol-A-base...

Ngày tải lên: 05/08/2014, 09:19

... only plot dynamic stress vs. dynamic strain, but also get E¢, E≤, E*, tan d, h*, and other dynamic properties for each cycle. This allows us to plot those properties as a function of dynamic stress ... detail of control in tuning the furnace. 4 .6 DYNAMIC EXPERIMENTS DMA experiments can be classed as temperature–time studies, frequency studies, and dynamic stress–strain curves. T...

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... Rheology, MIT, Cambridge, 1990. R. De le Garza, Measurement of Viscoelastic Properties by Dynamic Mechanical Analysis, Masters thesis, Univer- sity of Texas at Austin, 1994. R. Hagan, Polymer Testing, ... allows us to collect several vital pieces of information. Before we analyze the cure in Figure 6. 6 in more detail, we should mention that in curing studies, all three types of commerc...

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... LLC (a) (b) FIGURE 6. 9 Photo-cure of a UV curing adhesive in the DMA. Note the similarity to the materials in Figure 6. 1a and b. ©1999 CRC Press LLC FIGURE 6. 3 Effects of staging ... with thin films and adhesive coatings. A sample cure profile for a commercial two -part epoxy resin is shown in Figure 6. 6. From this scan, we can determine the minimum viscosity ( h *...

Ngày tải lên: 05/08/2014, 09:19

... close to the E ¢–E≤ crossover discussed in Chapter 6, and there may be little practical advantage in this approach in many cases. 7 .6 FREQUENCY STUDIES ON POLYMER MELTS The study of polymer ... see multiple frequencies in the actual use. Viscosity vs. frequency scans are used exten- FIGURE 7 .6 Temperature and frequency scans. Comparison of a modulus scan taken by scanning at...

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... stress relaxation modulus, E¢ is the storage modulus from the dynamic experiment, w is the dynamic test frequency, and E≤ is the dynamic loss modulus. A similar equation exists for the compliance, ... difficulties and failures exist today as did 20 years ago in applying this approach to various systems. 36 Some implicit assumptions exist about the mechanism of change within the sample...

Ngày tải lên: 05/08/2014, 09:19