Storage mechanism

Figure 11.9 Dynamic mechanical storage ( ) and loss ( ") moduli of isotropic PTT at 11 Hz showing the three relaxations [61]. From Dynamic mechanical relaxations of polyterephthalates based on trimethylene glycols, Gonzalez, C. C., Perena, J. M. and Bello, A., J. Polym. Sci., Polym. Phys. Ed., 26,1397-1408 (1988), Copyright (1988 John Wiley Sons, Inc.). Reprinted by permission of John Wiley Sons, Inc...

Fig. 23.4 Typical transition behavior in mechanical storage modulus for a semicrystalline polymer. The subscripts a and c refer to the amorphous and crystalline phases, of the polymer, with aa as the main 7g process.

Fig. 3. Stoichiometric DGEBA/DDS network M, versus prepolymer resin molecular weight. M . (M, calculated from equilibrium rubbery moduli at T = T, -h 45 K). O M, from equihbrium tensile experiments M, from 0.16 hz dynamic mechanical storage modulus measurements (After LeMay >)...

G.M. Dyson, E.F. Riley, Mechanical storage and retrieval of organic chemical data, Chem. Eng. News /1961, 74-80. 

Figure 9.22 Temperature dependence of mechanical storage modulus (Ef) at 10 Hz, (a) iPP and iPP/ EP84 blends and (b) iPP and iPP/EP77 blends. (From Reference 37 with permission from Elsevier Ltd.)...

Figure 25 Typical transition behavior in mechanical storage modulus and damping for a semicrystalline polymer. Relaxations in the amorphous phase are labeled with Greek letters (a, p, 7) with... 

Pig. 2. Dynamic Mechanical Storage Modulus for S/I/S Free Films with Molecular Orientation Parallel ( ) and Perpendicular (Jj to the Testing Direction (at 11 Hz). ... 

Measure the dynamic mechanical storage E as a function of temperature at different frequencies. 

An interesting analysis of a blend of PET/polycarbonate (PC), using MTDSC, was reported by Hale and Bair (Ref 5, p. 804) (Fig. 12). The conventional DSC curve (A) has all the indications of PET, but PC cannot be detected without the de-convoluted reversing curve (B) that indicates PC is present by virtue of its Tg that occurs in the same temperature range as the cold crystallization of PET. Further confirmation of the presence of PC is obtained from the dimamic mechanical storage modulus (curve C). The dynamic modulus technique will be discussed later in this article. 

Fig. 52. Dynamic mechanical storage modulus data measured over a range of frequencies during the isothermal cure (137°C) of the same epoxy-amine system (DGEBA/DDS) as in Figure 51 (120).

Figure 13.10. Mechanical and electromechanical response of a chiral smectic C elastomer as a function of the temperature for four dilferent frequencies, (O) 0.158 Hz, ( ) 1.12DHz, (A) 11.2 Hz, (V) 100 Hz (transition temperatures g Sx 308 K Sc 333 K Sa 346 K i). (a) E mechanical storage modulus, E" mechanical loss modulus (b) g electromechanical storage coefficient, g" electromechanical loss coefficient (c) g electromechanical storage modulus, g" electromechanic storage modulus.

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