Storage Modulus and Loss Tangent

Logarithmic plots of G and G against frequency reduced to I OO C encompassing the plateau zone, from curves IV of Figs. 2-3 and 2-4 (cf. also Fig. 12-9), for poly(n-octyl methacrylate). 

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Figure 3.16 Some experimental dynamic components, (a) Storage and loss compliance of crystalline polytetrafluoroethylene measured at different frequencies. [Data from E. R. Fitzgerald, J. Chem. Phys. 27 1 180 (1957).] (b) Storage modulus and loss tangent of poly(methyl acrylate) and poly(methyl methacrylate) measured at different temperatures. (Reprinted with permission from J. Heijboer in D. J. Meier (Ed.), Molecular Basis of Transitions and Relaxations, Gordon and Breach, New York, 1978.)...

Fig. 2. 53 Dependence of the storage modulus and loss tangent with temperature for 2,4PDMP ( ), 2,5-PDMP(t), 2,6 PDMP( ) and 3,5-PDMO(A). (From ref. [41])...

Figure 9. Effect of hard-segment content on storage modulus and loss tangent of compression-molded FTMO/FTMT-segmented copolymers...

Fig. 5. Calculated structural loss factor based on RKU model for three-layer composite with varying Young s storage modulus and loss tangent of viscoelastic layer.

Table I. Storage modulus and loss tangent values at room temperature and at 100 C for a series of 25/75 SIM PUR/PAc IPNs obtained with various amounts of stannous octoate...

Using a computerized data reduction scheme that incorporates a generalized WLF equation, dynamic mechanical data for two different polymers were correlated on master curves. The data then were related to the vibration damping behavior of each material over a broad range of frequencies and temperatures. The master curves are represented on a novel reduced temperature nomograph which presents the storage modulus and loss tangent plots simultaneously as functions of frequency and temperature. ... 

Figure 1. Dynamic shear storage modulus and loss tangent as a function of temperature for PS-0.02MAA-Na plasticized to varying degrees by diethylbenzene (DEB) curves 1, "5 2, 80 3, 84 4, 88 5, 92 6, 100 wt % polymer(adapted from ref. 25).

Fig. 14. Measurement under torsion G (storage modulus) and loss tangent of differently treated iPP injection moulded, annealed and hot-stretched samples. Parameters of the sample preparation are shown in the legend...

Storage Modulus and Loss Tangent of an Amorphous Polymer... 

Fig. 44. DMA shear storage modulus and loss tangent curves at 1 Hz for (a) polysulfone (—) and 30% 4,4 -dichlorodiphenyl sulfone/70% polysulfone(—), and (b) polycarbonate (— ) and 30% arochlor 5460 and 70% polycarbonate (—) (103). To convert Pa to dynes/cm, multiply by 10.

Figure 15 Storage modulus, (E ), loss tangent (tanS), and loss modulus, (E ), as a function of temperature for P7MB and P8MB at 3 Hz.

Fig. 2.67 Storage, loss modulus and loss tangent for ( ) PIPI, and (o) PIBI as a function of the temperature at 1 Hz. (From ref. [238])...

Viscoelastic data are commonly represented in the form of a master curve which allows the extrapolation of the data over broad temperature and frequency ranges. Master curves have, historically been presented as either storage modulus and loss modulus (or loss tangent) vs. reduced frequency. This representation requires a table of conversions to obtain meaningful frequency or temperature data. 

Temperature dependence of the mechanical tensile storage modulus, loss modulus, and loss tangent the precursor measured with a vibrating reed. The peak maximum frequencies in Hz are indicated. Moduli are in dyn cm". Reproduced from Ref. 45. Copyright 1978 American Chemical Society. 

Figure 22.3A, B depicts the storage modulus, loss modulus, and loss tangent as a function of temperature for polymer crosslinked silica aerogel (X-SiOx) with density 0.67 g/ cm and polymer crosslinked vanadia aerogel (X-VOx) with density 0.65 g/cm. At room temperature (23°C), the Young s modulus is 611/673 MPa for X-SiOx andX-VOx, respectively. As the temperature becomes lower the storage modulus increases. At — 119°C, the...

FIG. 15-10. Logarithms of storage shear modulus and loss tangent at I Hz plotted against.temperature for four methacylate polymers. (Me) methyl (Et) ethyl (n-Pr) -propyl (n-Bu) n-butyl. (He-ijboer. )... 

Dynamic mechanical analysis is the most widely used technique for the investigation of mechanical properties and the structure-property relationships in polymeric materials. The dynamic mechanical results expressed as storage modulus ( ), loss modulus ( ") and loss tangent (tan S) in the function of temperature demonstrate for example the phase composition, phase transition with glass transition temperature and the structural relaxation processes. The phase segregation in the cured UPRs with an increase in styrene concentration and the dependence of glass transition temperature of UPRs... 

As the sample softens through the low temperature transition, the storage modulus decreases, while the loss modulus and loss tangent show broad peaks. At the glass transition, E decreases greatly, while the loss modulus, E" and tan(5) show a sharp peak showing the onset of irreversible viscoelastic behavior. 

Figure 10 shows storage moduli and loss tangents of the samples with 83 and 93 Shore A hardness vs. temperature, as found by dynamic-mechanical thermal analysis (DMTA). The storage modulus has two transition points typical of... 

Figure 17 Variation of the storage modulus (E ) and loss tangent (tan5) at 3 Hz, for two PDEB specimens freshly quenched, and O aged for 14 months.

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