Dynamic mechanical properties of composites

Treatments such as mercerization/acetylation of fibers will result in an increase in the dynamic mechanical properties of composites, which was observed by Martins and Mattoso [40]. The stabilizing effect of lignin filler on NR was examined by Kosikova et al. [41], using DMA. Addition of hgnin improved the dynamic mechanical properties of NR vulcanizates. In another study. Da Costa et al. [27] found that addition of RHA to NR causes a shift in Tg values of filled mbber vulcanizates toward higher temperatures, showing the presence of cross-Unks,... 

This study examined the use of nanoclay reinforced rigid PVC as a matrix for wood flour filled rigid PVC composites. Particular emphasis was placed on examining the effects of nanoclay contents and coupling agent on the properties of the composites. In this context, the flexural, tensile and dynamic mechanical properties of composites made with nanoclay reinforced PVC matrix and ehitin were evaluated and compared to their counterparts made with unreinforced matrix. The following conclusions can be drawn from the experimental results ... 

Finer dispersion of silica improves the mechanical and dynamic mechanical properties of the resultant composites. Figure 3.11a and b compares the tensile properties of the acrylic copolymer and terpolymers in the uncross-hnked and cross-linked states, respectively. 

Akitsu, H., Gril, J., Morooka, T. and Norimoto, M. (1992). Dynamic mechanical properties of chemically modified wood (11). In Pacific Rim Bio-Based Composites Symposium Chemical Modification of Lignocellulosics, Plackett, D.V. and Dunningham, E.A. (Eds.). FRI Bulletin, 176, pp. 130-139. 

Wilson, W.T. "Effect of Radiation on the Dynamic Mechanical Properties of Epoxy Resins and Graphite Fiber/Epoxy Composites", 1986, Ph.D. Thesis, North Carolina State University, Raleigh, NC. 

The effect of polymer-filler interaction on solvent swelling and dynamic mechanical properties of the sol-gel-derived acrylic rubber (ACM)/silica, epoxi-dized natural rubber (ENR)/silica, and polyvinyl alcohol (PVA)/silica hybrid nanocomposites was described by Bandyopadhyay et al. [27]. Theoretical delineation of the reinforcing mechanism of polymer-layered silicate nanocomposites has been attempted by some authors while studying the micromechanics of the intercalated or exfoliated PNCs [28-31]. Wu et al. [32] verified the modulus reinforcement of rubber/clay nanocomposites using composite theories based on Guth, Halpin-Tsai, and the modified Halpin-Tsai equations. On introduction of a modulus reduction factor (MRF) for the platelet-like fillers, the predicted moduli were found to be closer to the experimental measurements. 

Some dynamic mechanical properties of glass fiber/ unsaturated polyester composites [39]... 

Figure 7. Dynamic mechanical properties of a model latex made with a uniform monomer feed composition...

ABA copolymers poly(methyl methacrylate)-polyisoprene-poly(methyl methacrylate) having polyisoprene with a high vinyl content as central block have been synthetized by Cole et al. 2I°. Dynamic mechanical properties of films of these ABA copolymers have been studied as a function of the copolymer composition, the temperature and the nature of the solvent (carbon tetrachloride, toluene, ethyl acetate, methylethyl ketone, dioxane) used for film preparation210. ... 

The dynamic mechanical properties of four 2,6-T-2P samples containing from 19 to 43 wt% hard segments are summarized in Figure 10. A low temperature s relaxation is apparent at about — 70°C for all compositions examined. The transition temperatures of these loss maxima and the associated activation energies are given in Table III. A second process, the c relaxation, can be noted as a shoulder on the high temperature side of the 8-loss maximum. The conclusion of this relaxation is marked by a change in slope of the loss modulus vs. temperature plots... 

B. Simard, and B. Ashrafi, The influence of a compatibilizer on the thermal and dynamic mechanical properties of PEEK/Carbon Nanotube Composites, Nanotechnology, Vol. 20, p. 315707,2009. 

J. D. Keenan, J. C. Seferis, and J, T. Quinlivan, J.A.P.S., 24, 2375, (1979) J. D. Keenan, Structure and Dynamic Mechanical Properties of TGDDM-DDS Epoxy, Graphite Fibers and Their Composites, M. S. Thesis, Department of Chemical Engineering, University of Washington, Seattle, Washington (1979). 

The varieties of copolymers that can be prepared with styrene have greatly expanded the use of the monomer. Dramatic improvements or modifications of physical properties can be achieved by choosing the right comonomer. The dynamic mechanical properties of these copolymers are strongly influenced by the characteristics of the comonomer, the copolymer composition and the miscibility parameter of the constituents parts to function as separable identities. 

Lewis, X B. and Nielsen, L. E. 1970. Dynamic mechanical properties of particulate-filled composites. J. Appl. Polym. Sci. 14 1449-1471. 

A variation of the torsion pendulum, torsional braid analysis (TBA), utilizes a supported specimen so that the dynamic mechanical properties of a sample can be monitored in the liquid as well as the solid states (1, 2). An inert multifilamented glass braid is impregnated with the sample (usually in its liquid state or in solution). The observed dynamic mechanical properties are relative due to the composite nature and complex geometry of the specimen. 

J. Gassan and A.K. Bledzki. Dynamic-mechanical properties of natural fiber-reinforced plastics the effect of coupling agents. In Fourth International Conference on Woodfiber-Plastic Composites, Madison, WI, May 12-14, 1997, pp. 76-80. 

Mechanical and Dynamic Mechanical Properties of Sisal PP Composites... 

X.-B. Yu, C. Wei, and F.-A. Zhang. Studies on the mechanical and dynamic mechanical properties of thermotropic liquid crystalline polymer/unsaturated polyester/glass fiber in situ hybrid composites. Polym. Adv. Tech., 17 534-539, 2006. 

S. Saikrasun and T. Amomsakchai. Isothermal decomposition behavior and dynamic mechanical properties of in situ-reinforcing elastomer composites based on thermoplastic elastomers and thermotropic liquid crystalline polymer. / Appl. Polym. ScL, 103 917-927, 2007. 

Kuruvilla, J., Sabu, T.I., Pavithran, C. Dynamic mechanical properties of short sisal fiber reinforced low density polyethylene composites. J. Reinf Plast. Compos. 12,139-154 (1993)... 

Dammstrdm, S., Salmdn, L., Gatenholm, P. The effect of moisture on the dynamical mechanical properties of bacterial cellulose/glucuronoxylan nano composites. Polymer 46, 10364-10371 (2005)... 

UVI0EC650 spectrometer. Japan Spectroscopic Co. We also examined the dynamic mechanical properties of the composites using dynamic viscoelastometei, Toyo Seiki Seisaku syo Ltd.. As the temperature dependence of the mechanical loss could not be measured when the specimen was prepared in the form of a thin film on a glass substrate, the films were removed from the glass with a blade and molded into a cylindrical shape 2 mm long and 5 mm in diameter. A dynamic compressive strain of 0.1 % at 10 H2 was applied to the specimen and the temperature dependeitce of the mechanical toss v as measured. 

Bleach, N.C., Nazhat, S.N., Tanner, K.E. et al. (2002) Effect of filler content on mechanictil and dynamic mechanical properties of paiticulate biphasic calcium phosphate - Polylactide composites. Biomaterials. 23, 1579-1585. 

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