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

... Thermosets 6. 1 Thermosetting Materials: A Review 6. 2 Study of Curing Behavior in the DMA: Cure Profiles 6. 3 Photo-Curing 6. 4 Modeling Cure Cycles 6. 5 Isothermal Curing Studies 6. 6 Kinetics by DMA 6. 7 ... Tests 3.10 Thermomechanical Analysis Notes Chapter 4 Dynamic Testing 4.1 Applying a Dynamic Stress to a Sample ©1999 CRC Press LLC dynamic measurements were an in...

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... environment of the samples. Examples include hydrogels tested in saline, 35 fibers in solutions, 36 and collagen in water. 37 UV light can be used to cure samples 38 to mimic processing or operating ... response of the fibers is greatly affected by the solution it is tested in. Similar tests in both dynamic and static modes are used in the medical, automotive, and cosmetic industries. T...

Ngày tải lên: 05/08/2014, 09:19

... m 2 /s 1 cSt = 1.00E- 06 m 2 /s 1 ft 2 /s = 0.0929 m 2 /s Work (Energy) 1 ft*lb = 1. 36 J 1 Btu = 1.05 J 1 cal = 4.1 86 kJ 1 kW*h = 3 .6 MJ 1 eV = 1.6E-19 J 1 erg = 1 .60 E-07 J 1 J = 0.73 ft*lbF ... = 90 .6 kph 55 mph = 89.1 kph 55 mph = 245.9 m/s 90 kph = 55 .6 mph Acceleration 1 ft/s 2 = 0.3 m/s 2 1 free fall (g) = 9.8 066 50 m/s 2 ©1999 CRC Press LLC...

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... reciprocal, 13 and roughly related as (3.5) The analysis of the stress relaxation curve is shown in Figure 3.8a and is analogous to the creep analysis. One interesting application of the stress ... 3.11b). Since many materials are used in contact with a dissimilar material FIGURE 3.10 Thermomechanical analysis test methods in common use. Dilatometry allows one to measure volumetric...

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... 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 *...

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... 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