Tan 6 vs. temperature

Figure 3. Dielectric loss factor, tan 6, vs. temperature for different PP-PC blend compositions at 0.06 KHz.

Figure 8.19. Tan 6 vs. temperature for several IPN s. The loss tangent of semicompatible compositions remains high over a broad temperature range. (Huelck et al, 1972.)...

The damping factor, tan 6 vs. temperature for the pseudo and full IPN s showed two peaks corresponding to the Tg s of the polyurethane and the acrylic copol3nner networks. The size of the damping peaks changed systematically with concentration of the alloys, i.e., decreased with the component concentration. 

Fig. 8. G and tan 6 vs temperature of a 1 1 blend of styrene-butadiene rubber with polv(tert-butvl styrene) resin.

Materials HBPI(ODPA-MTA)ll and LPI(ODPA-MDA)ll were analyzed by using a d3mamic-mechanical analysis (DMA). The records (tan 6) vs temperature of both materials, which are very different, are shown in Figure 16 a,b. 

Fig. 7 Tan 6 vs. temperature plots of epoxy/m-HNTs nanocomposites (reproduced with permission of Springer, M. Liu et al.. Journal of Polymer Research [25])...

Figure 6. Plot of tan 8 vs. temperature for plasma-polymerized ethane formed at 0.5 ton, 20 cmsSTP/min, 5 W, and KHz. Film thickness was 820 A. (9) Measured at 1 KHz and (X) measured at 10 KHz.

Our study of pure polyurethane, PU/E, and PU/E/UPE IPN elastomers, has shown that IPNs have very broad glass transitions (broad tan S vs. temperature peak) centered around room temperature. The pure polyurethanes have a relatively high and sharp T well below RT. Fillers such as mica and graphite have not shown any significant effect on tan 6 height or temperature range. 

Figure 10. Plot of tan 8 vs. temperature for PPO-400 samples with increasing salt contents (left to right 0, 2.9, 6.1, 9.6, and 13.6 mol %)...

Figure 7.1 6 Complex shear modulus and tan 5 vs. temperature for an IPN containing inverted coreshell particles of SAN/poly ethyl hexyl methacyriate (El-Aasser, M. S. et a/., Colloids Surf A, 153, 241, 1999) Elsevier.

Plots of the tan 6 peak temperature vs concentration, according to the Pox equation, show a straight line... 

Tan 6 peak temperature vs concentration for blends of natural rubber with compatible resins. 

Fig. 6 (a) Storage modulus and (b) tan 5 vs. temperature for NR (open circle) and composites with 1 (filled triangle), 2.8 (filled diamond), 5.4 (filled circle) and 8.3 (open square) wt% MWCNT. Inset of Figure b shows the maximum of tan 5 with filler concentration exhibiting linearly decreasing order [99]... 

Figure 6.19 shows the tan S vs. temperature at 1 Hz frequency for the SPTES polymers. The maximum damping peaks of SPTES-100 appear at 202 and 238°C. 

An additional relaxation can be detected in plots of the loss tangent as a function of temperature for 2,6-T-2P-43, not shown. The relaxation occurred at 60°C (11 Hz) in the first examination of this sample. A weak ah relaxation can be detected in the loss modulus vs. temperature plots in Figure 13, but the process is more readily apparent in the tan(8) data. Upon retesting of this sample, the h dispersion was shifted to 71 °C. The activation energy for the ah relaxation did not change significantly with thermal history and was extremely weak or undetectable in 2,6-T-2P samples which contained less than 43 wt% hard segments. 

FIG. 13.6 The mechanical spectra (log G and A, i.e. n tan <5, at 1 Hz vs. temperature) for copolymers of styrene and butadiene (random, block and graft) and their homopolymers. From McCrum, Buckley and Bucknall, 1988. Courtesy Oxford University Press. 

Tan 6 (loss tangent) at 6.5 GHz vs. temperature for four-folded stretched emeraldine (P(ANi)) hydrochloride parallel to the stretch direction (x), perpendicular to the stretch direction ( ), unoriented poly(orthotoluidine) hydrochloride (o) and unoriented self-doped sulfonated polyaniline (+). After Reference [190], reproduced with permission. 

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