Tensile properties, experimental

Reactivities of Amines in Homogeneous Systems (14, 17). The decrease in the tensile properties of the vulcanized rubber during aging may be attributed to the degradation of the rubber molecule by oxidation. This may be supported by the experimental result in the oxidation of rubber solution. 

Deng et al. (8) investigated the tensile properties of PEEK/MWCNTs, and found increases in the elastic modulus and yield strength at temperatures above and below Tg at 25°C, the tensile modulus increased by -90% for composites including 15 wt% MWCNTs, and the increment reached -160% at 200°C. According to those results, the improvement of MWCNTs in the mechanical behaviour of the matrix is more effective at higher temperatures. Experimental results do confirm that the overall mechanical performance of PEEK/CNT nanocomposites is well above the required for potential aircraft applications. 

In the last ten years, a great deal of experimental work has been presented about the tensile properties of CNTs/polymer composites in the literature. However, it is difficult to generalize across these studies because of the large number of parameters that can influence the effective properties, including size and structure of the CNT, CNT/ polymer interaction, processing techniques and processing conditions. In this chapter, the effect of structure and morphology on the properties of the nanocomposites will be focused and discussed. 

The main experimental methodology used is to directly characterize the tensile properties of CNTs/polymer composites by conventional pull tests (e.g. with Instron tensile testers). Similarly, dynamic mechanical analysis (DMA) and thermal mechanical analysis (TMA) were also applied to investigate the tensile strength and tensile modulus. With these tensile tests, the ultimate tensile strength, tensile modulus and elongation to break of composites can be determined from the tensile strain-stress curve. 

Tensile properties of composite propellants depend on the tensile properties of the matrix, concentration of the components, particle size, particle-size distribution, particle shape, quality of the interface between fillers and polymeric binder, and, obviously, experimental conditions (strain rate, temperature, and environmental pressure). Many authors (2, 3) have explained the effect of fillers on the mechanical properties of composites, the importance of the filler-matrix interface on physical properties, and the mechanism of reinforcement of the material. Other efforts have examined the effect of experimental conditions on the failure properties of filled elastomers. Landel and... 

Tensile properties are obviously whole hber properties, as opposed to surface properties, and it has been suggested that they are cortical properties not related to the cuticle. This is because of experimental evidence and is, in part, due to the importance of the alpha to beta transformation that occurs on stretching [5]. Wolfram and Lindemann [6] have suggested that the cuticle does contribute to the tensile properties, especially in thin hair. However, Scott [7] has provided support for the no cuticle involvement hypothesis, by evaluating the tensile properties of hair hbers that were abraded under controlled conditions. In no instance could he demonstrate a signihcant change in tensile properties where only cuticle had been abraded. 

Ivanov DS, Lomov SV, Bogdanovich AE, Karahan M, Verpoest I. A comparative study of tensile properties of non-crimp 3D orthogonal weave and multi-layer plain weave E-glass composites. Part 2 Comprehensive experimental results. Composites Part A 2009 40 1144-57. 

The experimental results that will be examined consist of studies that look at the ability of a random copolymer to improve the properties of mixtures of the two homopolymers relative to the ability of a block copolymer. The three different systems that are examined include copolymers of poly(styrene-co-methyl methacrylate) (S/MMA), poly(styrene-co-2-vinyl pyridine) (S/2VP), and poly(styrene-co-ethylene) (S/E) in mixtures of the two homopolymers. The experiments that have been utilized to examine the ability of the copolymer to strengthen a polymer blend include the examination of the tensile properties of the compatibilized blend and the determination of the interfacial strength between the two homopolymers using asymmetric double cantilever beam (ADCB) experiments. 

Pis obtained by CVD exhibits better tensile properties and lower gas permeability in comparison to samples obtained from solution easting. This is attributed to crosslinking reactions in the PI obtained by CVD. Details of a recent experimental semp have been discussed in the litera-... 

Tur] Turkdogan, E.T., Ignatowicz, S., Tensile Properties of Nitrogen-austenitized Chromium Steels , J. Iron Steel Inst, 199, 287-296 (1961) (Experimental, Thermodyn., Phase Relations, Meehan. Prop., 21)... 

Ikel] Ikeda, M., Komatsu, S., Inoue, K., Shiota, H., Imose, T., Effect of Chromimn Content on Electrical Resistivity and Tensile Properties of Ti-Fe-Cr Alloys , Mater. Sci. Technol, 16 (6), 605-608 (2000) (Experimental, Meehan. Prop., Morphology, 20)... 

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