Polymer composites shear elastic modulus

Economical soy products including SPI, DSF, SPC, and SSF can be mixed and coagulated with polymer latex in the aqueous phase to form dry composites with significantly enhanced modulus. These dry soy products have a shear elastic modulus of 1-5 GPa within the temperature range of -40 to 140 C. The carboxylated styrene-butadiene composites filled with these soy products show a significant increase of shear modulus compared to that of the polymer matrix alone. The different compositions of these soy products generate a different reinforcement effect and approximately follow the order SPC > DSF > SSF SPI. The dehydration of these soy reinforcement fractions causes the... 

From the experimental results, the ER effect in polymer gels is explained as follows (Fig. 8). When an electric field is applied, the particles electrically bind together and cannot slip past each other. Larger shear forces are needed in the presence of an electric field. Thus, the electric field apparently enhances the elastic modulus of the composite gel. The difference in ER effects between an oil and a gel is that the polarized particles necessarily cannot move between the electrodes to produce the ER effect in a gel. In order for the ER effect to occur, it is important to form migration paths before application of an electric field. 

Researchers have performed experiments on CNT-polymer bulk composites at the macroscale and observed the enhancements in mechanical properties (like elastic modulus and tensile strength) and tried to correlate the experimental results and phenomena with continuum theories like micro-mechanics of composites or Kelly Tyson shearing model [105,115-120]. 

Dynamic mechanical characteristics, mostly in the form of the temperature response of shear or Young s modulus and mechanical loss, have been used with considerable success for the analysis of multiphase polymer systems. In many cases, however, the results were evaluated rather qualitatively. One purpose of this report is to demonstrate that it is possible to get quantitative information on phase volumes and phase structure by using existing theories of elastic moduli of composite materials. Furthermore, some special anomalies of the dynamic mechanical behavior of two-phase systems having a rubbery phase dispersed within a rigid matrix are discussed these anomalies arise from the energy distribution and from mechanical interactions between the phases. 

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