Nylon Dynamic mechanical properties

Research concerning nylon-elastomer blends has mostly focused on the improvement of mechanical and thermal properties. Their dynamic mechanical properties are quite important both for processing and engineering applications. Wang and Zheng have smdied the influence of grafting on the dynamic mechanical properties of a blend based on nylon 1212 and a graft... 

Reactor exposure causes decrease in elongation at break and increase in the modulus of elasticity due to crosslink formation [434]. High doses are, however, required to produce appreciable change. 7-Irradiation gives decreased tensile strength and elongation at break for nylon 6 and nylon 6, 6 [433] (Fig. 47). The dynamic mechanical properties of nylon 6, 6 were studied by Sauer et al. [436] after neutron irradiation. Rubber-like behaviour was observed for temperatures above the main softening temperature. 

The effects of high humidity on the dynamic mechanical properties and thermal transitions of a commercial nylon-epoxy adhesive have been reported by Butt and Cotter." Exposure of the cured adhesive to 43°C and 97% RH for times ranging from 142 h to 2,040 h resulted in a substantial decrease (as much as 82%) in the complex dynamic tensile modulus. Some of the results of these authors are shown in Table I. The thermal transitions... 

Yu Z-Z, Yan C, Yang M S and Mai Y-W (2004) Mechanical and dynamic mechanical properties of nylon 66/montmorillonite nanocomposites fabricated by melt compounding, Polym Int 53 1093-1098. 

Figure 3-4. Dynamic mechanical properties by torsion pendulum versus temperature of a typical semicrystalline thermoplastic (nylon G, dry) showing effects of glass transition and crystalline melting transition and method of determining their onsets. (Reprinted with permission of McGraw-Hill Company.)...

Jha A. and Bhowmick A.K., Thermoplastic elastomeric blends of nylon 6/acrylate rubber Influence of interaction of mechanical and dynamic mechanical thermal properties. Rubber Chem. TechnoL, 70, 798, 1997. 

The heat deflection temperature (or heat distortion temperature) is an important material property mostly used to determine a material s useful temperature operating range. It refers to the temperature below which a moulded object can hold its own shape. It can be determined using a dynamic mechanical analyser set to apply a constant force. The HDT was determined for blends of plasticized soy flour (52% protein) and polyamide (nylon) as 45 °C when plasticized with 20 wt% sorbital, 35 °C when plasticized with 20 wt% glycerol, and 39 °C when plasticized with 10 wt% of each." When such a blend is used to make composites with natural flbres, increasing content of natural fibres also increased the HDT. 

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