Impact and Bursting Strength

The ability of a polymer to resist fracture when exposed to a sudden impact is the basis of tests for impact strength. These are loosely related to the toughness of the polymer, and fall into two main categories those suited for film and those suited for sheet. 

The dart drop impact test, ASTM D1709 and ASTM D4272, is often used for film samples. In D1709, a sample of the film is subjected to an impact by a round- 

For polymer sheets, the notched Izod impact strength is often reported (ASTM D256). In this test, as well as the Charpy impact test in the same ASTM standard, the polymer sample is subjected to an impact from a falling hammer, and the 

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