Tensile impact testing parameters

The materials and morphological parameters are usually studied as function of test temperature and test speed. The Izod method as function of temperature (9,10) is standard. Also studied is the Charpy impact behavior, both as a function of test temperature and test speed (12). With a notched tensile impact test, both test speed and test temperature can easily be varied (I, 2,13). 

Ligament Thickness. The ductile-to-brittle transition as measured in notched Izod, notched Charpy, and notched tensile impact tests is discontinuous and is dependent on both rubber concentration and particle size. These two parameters can be combined into a new morphological parameter that governs the ductile-to-brittle transition. The ligament thickness (interparticular distance), which is a function of rubber concentration and particle size,... 

Besides impact testing, quasi-static measurements are carried out to assess the Young modulus, E, the yield stress, cry, and the elongation at break, break> as the most current parameters. They follow international standards (e.g. ISO 527 for tensile tests, ISO 178 for bending measurements). 

Tensile, impact, and flexural properties Tensile test is the most widely used method to evaluate the mechanical properties of the resultant nanocomposites, accordingly. Young s modulus, tensile strength, and elongation at break are the three main parameters obtained. These vary with the silica content, but the variation trends are different. Furthermore, the impact test is also widely used for mechanical property characterization. 

As far as the mechanical properties are concerned, the tear (test name Elmendorf tear), impact (test name dart drop), and tensile strengths give an indication of the mechanical strength of the tubular film. Some of these properties and the effect the processing parameters have on them were discussed in Section 1.2. The amorphous as well as the crystalline orientation developments during the blowing process depend on... 

First, the role of rubber modification in high rate impact is to suppress spallation by inducing the material to yield in the presence of dynamic tensile stresses arising from impact. Second, this yield-spall transition occurs at different strain rates for different rubber contents and may be predictable using quasistatic, low temperature tests of this type. These tests can also provide information concerning the basic nature of the yield process in these materials through the activation parameters which are obtained. Third, the Bauwens-Crowet equation seems to be a good model for the rate and temperature sensitive behavior of the American Cyanamid materials and is therefore a likely candidate for a yield criterion to use in the analytical code work on these materials which we hope to perform as a continuation of this work. 

Polymer blends must provide a variety of performance parameters. Usually it is a set of performance criteria that determines if the material can be used or not. For specific application more weight can be given to one or another material property. The most important properties of polymer blends are mechanical. Two type of tests have been used the low rate of deformation — tensile, compressive or bending and the high speed impact. Immiscibility affects primarily the maximum elongation at break, and the yield stress. 

To meet customer tolerances. Most of the properties measured are from composite sample. Some properties are measured more frequently. Blend is manufactured in accordance with customer specification. The following parameters are included in testing density, tensile strength, elongation, flexural modulus, Izod impact, Shore A and Rockwell C hardness, and HDT. 

The relevant results of the tests are shown in Table 2. In our experience four parameters provide a very useful representation of the radiation tolerance of PP formulations. These are the color, tensile elongation at break, Gardner impact strength at 23°C, flexural deflection at peak load. 

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