Dynamic viscoelastic properties

Fig. 21. Dynamic viscoelastic properties of a low density polyethylene (LDPE) at 150°C complex dynamic viscosity Tj, storage modulus G and loss modulus G" vs angular velocity, CO. To convert Pa-s to P, multiply by 10 to convert Pa to dyn/cm, multiply by 10.

It seems that results rather close in their meaning should be obtained, provided that monodisperse polymers are taken as dispersion media. Investigations into dynamic (viscoelastic) properties of such liquids with highly active filler have shown that [6],... 

Thermal and thermomechanical analyses44 are very important for determining die upper and lower usage temperature of polymeric materials as well as showing how they behave between diose temperature extremes. An especially useful thermal technique for polyurethanes is dynamic mechanical analysis (DMA).45 Uiis is used to study dynamic viscoelastic properties and measures die ability to... 

The dynamic viscoelastic properties of acetylated wood have been determined and compared with other wood treatments in a number of studies. Both the specific dynamic Young s modulus (E /j) and tan S are lower in acetylated wood compared with unmodified wood (Akitsu etal., 1991, 1992, 1993a,b Korai and Suzuki, 1995 Chang etal., 2000). Acetylation also reduces mechanosorptive creep deformation of the modified wood (Norimoto etal., 1992 Yano etal, 1993). In a study of the dynamic mechanical properties of acetylated wood under conditions of varying humidity, it was concluded that the rate of diffusion of moisture into the wood samples was not affected by acetylation (Ebrahimzadeh, 1998). 

Suzuki, M., Araki, M. and Goto, T. (1963a). Water sorption and dynamic viscoelastic properties of untreated, HCl-treated and HCHO-treated wood. Mokuzai Gakkaishi, 9(1), 11-17. 

Massa,D,J., Schrag,J.L., Ferry,J.D. Dynamic viscoelastic properties of polystyrene in high-viscosity solvents. Extrapolation to infinite dilution and high-frequency behavior. Macromolecules 4,210-214 (1971). 

Tanaka,H., Sakanishi,A., Kaneko,M., Furiuchi,J. Dynamic viscoelastic properties of dilute polymer solutions. J. Polymer Sci. Pt. C15,317-330 (1966). 

It is important to quantify the dynamic viscoelastic properties of the materials. Normally the analysis of these systems is performed using the frequency as the variable, and the relationship between the dynamic parameters and the parameters for step-function suppose the application of an oscillatory shear strain with angular frequency w expressed as ... 

Finally it may be remarked that the dynamic viscoelastic properties of plasticized cellulose derivatives seem to give no evidence of any unusual temperature dependence of the chain conformations. Thus, Landel and Ferry (162, 163, 164) successfully applied the method of reduced variables [see, for example, Ferry (6)] to various concentrated solutions of cellulosic polymers, and found that the temperature reduction factors were quite similar to those for other flexible polymers such as poly(isobutylene). 

The theory is not limited in its application to the transient properties of amorphous polymers it can be used to make molecular interpretation and prediction of the dynamic viscoelastic properties of crosslinked polymers [24] as well. According to the Fourier-Laplace transformation, the complex tensile modulus can be separated into the real and imaginary parts... 

The effect of amplitude-dependence of the dynamic viscoelastic properties of carbon black filled rubbers has been known for some 50 years, but was brought into clear focus by the work of Payne in the 1960s [1-7]. Therefore, this effect is often referred as the Payne-effect. It has been also investigated intensively by... 

Mills, P. and Kokini, J. L. 1984. Comparison of steady shear and dynamic viscoelastic properties of guar and karaya gums. J. Food Set 49 1-4 and 9. 

Fig. 13. Dynamic viscoelastic properties of ATS resin. Reproduced with permission from Journal of Applied Polymer Science, 27,571,1982. Copyright 1982 John Wiley Sons, Inc.

Dileep, A.O., Shamasundar, B.A., Binsi, P.K., Badii, R, and Howell, N.K. 2005. Effect of ice storage on the physicochemical and dynamic viscoelastic properties of ribbonfish (Trichiurus spp.) meat. Journal of Food Science 70 537-545. 

Small amplitude dynamic viscoelastic properties of apple butter, mustard, table margarine, and mayonnaise were compared to their respective properties in steady shear flow in the range of shear rates and frequencies of 0.1 to 100 sec" (Bistany and Kokini, 1983). Comparisons of dynamic and steady viscosities showed that dynamic viscosities (tj ) are much greater than steady viscosities (17). Consequently, the Cox-Merz rule is not obeyed (Bistany and Kokini, 1983). This phenomenon can be explained by a signifi-... 

Munoz, J., and Sherman, P. (1990). Dynamic viscoelastic properties of some commercial salad dressing. J. Text. Stud. 21, 411-426. 

Richard, J., Dynamic viscoelastic properties of polymer latex films Role of core chains and particle particle interfaces. /K 5T PMSE. Fall, Chicago. 73. 41 42 (1995). 

Kajiyama T, Tanaka K, Ohki I, Ge S-R, Yoon SJ, Takahara A (1994) Imaging of dynamic viscoelastic properties of a phase-separated polymer surface by forced oscillation atomic force microscopy. Macromolecules 27 7932-7934... 

Fig. 3. Influence of silane coupling agent on dynamic viscoelastic properties of GF/PP composites (a) storage modulus as a function of angular frequency, (b) loss modulus as a function of angular frequency...

Fig. 18. Relationship between dynamic viscoelastic properties and volume fraction of fiber for GFL/PP composites at the angular frequency of 1.257 rad/s (a) storage modulus, (b) dynamic viscosity...

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