Tensile and Flexural Properties

From such studies it is possible to optimize individual properties, such as impact strength, hardness, and flexural and tensile properties, and, within limits, to adjust optical clarity to the maximum attainable at the preferred levels of performance parameters. 

The flexural and tensile properties of polyester composites at various fiber volume fractions are listed in Table I. Strength values increase up to a fiber volume fraction of about 40% but then decrease with increased fiber volume fraction. This is caused by the poor wetting and extensive fiber damage which occurs at higher volume fractions because of compaction and close packing of the fibers. The ultimate flexural strain shows a similar trend. The modulus values increase almost linearly with fiber volume fraction. 

H. Rozman, G.S. Tay, R.N. Kumar, A. Abusamah, H. Ismail, and Z.A. Mohd Ishak, Polypropylene-oil palm empty fruit bunch-glass fibre hybrid composites a preliminary study on the flexural and tensile properties. Eur. Polym. J. 37(6), 1283-1291 (2001). 

Seldon [10] measured the weld line strength and impact, and flexural and tensile properties of injection-molded specimens of glass fiber-reinforced polyamide 6 and talc-filled polypropylene (PP). Further information was obtained by examination of fracture surfaces by scanning electron microscopy. 

The fiber mass fraction, and the flexural and tensile properties of the continuous fiber-reinforced composites produced by various techniques were determined according to ISO 1172, ISO 178, and EN 60, respectively. The split disk test method according to ASTM 2290 was employed to determine the circumferential strength and modulus of the pipes produced by filament winding. 

Those stmctural variables most important to the tensile properties are polymer composition, density, and cell shape. Variation with use temperature has also been characterized (157). Flexural strength and modulus of rigid foams both increase with increasing density in the same manner as the compressive and tensile properties. More specific data on particular foams are available from manufacturers Hterature and in References 22,59,60,131 and 156. Shear strength and modulus of rigid foams depend on the polymer composition and state, density, and cell shape. The shear properties increase with increasing density and with decreasing temperature (157). 

Tensile, flexural, and impact properties based on 3.1-mm thick ASTM specimens. 

The data available on the effect of accelerators on the flexural and tensile strengths and the modulus of elasticity are limited [22, 30, 31] and are relevant only to calcium chloride and triethanolamine. The data generally point to either no effect or a slight reduction in all three properties. Also, in view of the increase in compressive strength, it is reasonable to assume that for a given compressive strength, the presence of calcium chloride or triethanolamine will reduce the flexural and tensile strengths and the modulus of elasticity. 

In addition, ASA may be blended with other polymers that themselves exhibit high heat distortion temperatures. For example, blends of poly(ether imide) and ASA exhibit an improved heat distortion temperature, improved flexural properties and tensile properties in comparison to the ASA component alone and have lower impact strengths as well (35). The statement above has been exemplified using Ultem 1000 as a poly(ether imide) resin and Geloy 1020 as ASA component. 

Typical physical properties for an injection-molded transparent acrylic polyblend resin are given in Table II. The injection molding conditions used are given in Table III. Tensile, flexural, and impact properties are within the range reported for typical ABS and high impact polystyrene resins. Optical properties approach those of the acrylics [i.e., poly (methyl methacrylate)]. The strength properties are on the low side of those reported in the first paper for the transparent diene... 

Flexural strength and modulus of rigid foams increase with increasing density in the same manner as the compressive and tensile properties. 

Table in also shows the effect of BG content on the properties of injection-molded BDft/BG/BD polyesters. The two copolyesters which contained 65 and 73 mol % BG and did not solidify during preparation were molded in their anisotropic state (Ti s above molding temperatures), and it is significant that these two ICP s have the highest tensile, flexural, and impact properties (and the highest HOT s at 264 psi stress). The other four compositions in the table became solid or semi solid during preparation at 300°C, and additional molecular weic t buildup was achieved by solid-state polymerization to give I.V. s comparable to... 

CaCO EPR rubber rubber silicone maleates fatty acid silanes PDMS decreased disperse component of the surface energy filler surface energy approaches surface energy of matrix decreased tensile strength and flexural cracking increased green strength, Mooney viscosity, and tensile properties surface hydrophobization resistance to solvent extraction and water 21 49 49 37... 

The physical properties of these mortars show phenomenally high flexural and tensile strengths, with little or no loss in compressive strength. For all practical purposes, a level of 2% as an addition cate, produces results which are outstanding, without excessive cost. Cured mortar specimens have been e qiosed to continuous water immersion with no loss in properties. ... 

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