Tensile Strength and Elongation at Break

The tensile strengths showed linear behaviour or fairly small curvature but the direction varied with compound. In the worst case (natural A), 75% of the strength was lost but generally changes were considerably less than this. Compoimds hntyl J, hutyl K, polychloroprene L, and nitrile P generally showed least change whilst acrylate S, Hypalon T, polysulphide W, and silicone X tended to rise in strength. 

The ranking as given by mechanical tests, in particular the product of tensile strength and elongation, will he considered in a subsequent paper. 

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Table 10.3 Effect of straining rate on the measured tensile strength and elongation at break of two samples of polyethylene...

Tensile strength and elongation at break has been determined by an Instron mechanical analyzer, and the results are as shown in Fig. 10, 11, and 12. 

Compatibility and various other properties such as morphology, crystalline behavior, structure, mechanical properties of natural rubber-polyethylene blends were investigated by Qin et al. [39]. Polyethylene-b-polyiso-prene acts as a successful compatibilizer here. Mechanical properties of the blends were improved upon the addition of the block copolymer (Table 12). The copolymer locates at the interface, and, thus, reduces the interfacial tension that is reflected in the mechanical properties. As the amount of graft copolymer increases, tensile strength and elongation at break increase and reach a leveling off. 

Data are presented which illustrate that the tensile strength and elongation-at-break depend significantly on the extension rate even when the stress remains in equilibrium with the strain prior to fracture. A crude estimate was made of the threshold (lowest possible) values of the true stress-at-break and the elongation-at-break for the TIPA elastomer. The estimated quantities are about 26% less than those found at an extension rate of about 0.01 min-1 at 30°C. 

ISO 527-4 1997 Plastics - Determination of tensile properties - Part 4 Test conditions for isotropic and orthotropic fibre-reinforced plastic composites ISO 527-5 1997 Plastics - Determination of tensile properties - Part 5 Test conditions for unidirectional fibre-reinforced plastic composites ISO 1798 1997 Flexible cellular polymeric materials - Determination of tensile strength and elongation at break... 

For three- and ten-year outdoor exposures of 3-mm-thick samples, retentions of tensile strength and elongation at break can be, for example ... 

After 15-year outdoor exposures of 0.1-0.15 mm thick films, the retentions of tensile strengths and elongations at break range from 91% up to 125% without visible change. These results are examples only and cannot be generalized. 

Figure 4.124 shows two examples of the retention of tensile strength and elongation at break for a film exposed to the Weather-Ometer. 

Somewhat greater tensile strength and elongation at break are obtained with high-energy electrons than with gamma radiation, when exposure is... 

The effect of angle of applied stress on modulus, tensile strength, and elongation at break was further studied for a 30-volume fiber glass composite in a formulation identical to the standard formulation, except that the silica was reduced to 15 parts per hundred. The results for modulus are illustrated in Figure 18 where the data show good agreement with the theoretical relationship developed by Lees (6). 

Copolymer test specimens were prepared by pressing slabs for 0.5-3 min at temperatures approximately 20°C above the copolymer melting point, followed by cooling under pressure to room temperature in 5-10 min. Test samples were conditioned at 24°C and 50% relative humidity for at least 48 hr before testing. Stress-strain and tear-strength measurements were made on 0.6 to 0.8-mm-thick specimens. Thicker specimens yield lower values for tensile strength and elongation at break. The test methods used were ... 

The resulting TPE can either be used alone or blended with aliphatic oil and polypropylene. In the former case a higher tensile strength and elongation at break are obtained in comparison with the commercially available styrene-hydrogenated butadiene-styrene block copolymers, especially at high temperatures. 

ISO 1798-83 Polymeric Materials, Cellular Flexible —Determination of Tensile Strength and Elongation at Break, 2 pp... 

Fig. 6 (A) Tensile strength and elongation at break and (B) for PEO/ clay nanocomposites.

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