The testing of polymeric materials has become decidedly different and as technology improves, it is necessary to evaluate the accuracy of results based on testing methods, particularly when functional durability is critical. The research discussed in this paper focuses on the effect of changing a variety of test parameters in relation to the falling dart impact test, more commonly referred to as the Gardner impact test (ASTM D5420).

1. The Effect of Testing Parameters on the Functional Impact Resistance of UPVC Commercial Products Akshay Agarwal Joshua Anthony Liam Driscoll 2011 SPE ANTEC Vinyl Division

2. Abstract Advancements in technology have expanded the range of acceptable testing methods Accuracy* of these methods needs to be determined *Repeatability within a lab and reproducibility among labs Research focused on the effect of changing testing parameters for the falling dart impact test (Gardner Impact Test - ASTM D5420) 2 2011 SPE ANTEC Vinyl Division

3. Advantages of Gardner Impact Test Minimal cost Ease-of-use Commingled effect of material of choice, design, processing, and assembly variables Realistic geometries, testing environment, and end-use impacting speeds (strain rates) 3 2011 SPE ANTEC Vinyl Division

4. References Nunnery – ANTEC 1993 – Questioned the value and relevance of conventional Izod testing and HDT Lavach – ANTEC 1998 – Concluded that the mass of the base of the testing unit affects the variation in regards to the MFE Lutz & Goldman – ANTEC 1979 – Investigated modified falling weight tests to qualify low temperature, impact resistant PVC 4 2011 SPE ANTEC Vinyl Division

5. References Tryson, Takemori, and Yee – 1979 – Investigated the effect of specimen geometry and plunger radius of ductile and brittle materials Sabbagh & Marchand– ANTEC 2003 – Investigated the ductile to brittle transition temperature in relation to quality control Driscoll – ASTM STP (HOUSTON 1985) – Instrumented Impact Testing of Plastics and Composite Materials 5 2011 SPE ANTEC Vinyl Division

6. Research Parameters One standard rigid vinyl formulation Three Samples Two colors (white vs. tan) Two textures (smooth vs. texture) Two surface sections Two probe diameters (O.D.) Four support rings (I.D.) Three tup weights Total of 144 test conditions 6 2011 SPE ANTEC Vinyl Division

7. Research Parameters 7 2011 SPE ANTEC Vinyl Division

8. Protocol The following series of slides illustrates the effect of probe diameter (O.D.) against varying support rings (I.D.) and tup weights for the material candidates 8 2011 SPE ANTEC Vinyl Division

9. Material 1 Results The 0.91kg tup produced higher MFE variation Proportional to the support ring diameter 23% variation achieved with 1.27cm probe 6% variation achieved with 1.59cm probe 9 2011 SPE ANTEC Vinyl Division

11. Material 2 Results Variability directly related to interaction between the tup weight and support ring diameter Greater reliability with greater weights across the range of support ring diameters 17% variation achieved with 0.91kg tup and 1.27cm probe 7% variation achieved with 0.91kg tup and 1.59cm probe 11 2011 SPE ANTEC Vinyl Division

13. Material 3 Results Similar trend observed 23% variation achieved with 0.91kg tup and 1.27cm probe 13% variation achieved with 0.91kg tup and 1.59cm probe 13 2011 SPE ANTEC Vinyl Division

15. Comparison of Impact Section Based on thousands of impact events, section two (bottom) always exhibited lower MFE values for each material 15 2011 SPE ANTEC Vinyl Division

16. Conclusions /1 Based on entire sample population: Least reliable test setup (high bias/fair precision): 0.91kg tup 1.27cm probe diameter 6.35cm support ring diameter Ratio of 5:1 Most reliable test setup (low bias/fair precision): 1.82kg tup 1.59cm probe diameter 3.81cm support ring diameter Ratio of 2.4:1 16 2011 SPE ANTEC Vinyl Division

17. Conclusions /2 Based on entire sample population: Most repeatable test setup (highest precision): 3.63kg tup 1.27cm probe diameter 6.35cm support ring diameter Ratio of 5:1 17 2011 SPE ANTEC Vinyl Division

18. Conclusions /3 Single laboratory analysis equals repeatability No attempt to investigate multi-laboratory reliability The 1.27cm appears to be the most biased probe diameter…however, this is the preferred geometry in all three ASTM protocols Lower weight tup (0.91kg) produced higher variability across support ring diameters 18 2011 SPE ANTEC Vinyl Division

19. Goldman and Lutz Revisited Following the protocol reported in the 1979 ANTEC paper (“scratched product”), a further investigation of “Pre- and Post-installed product” using the “UML Protocol” showed dramatic changes in impact behavior 19 2011 SPE ANTEC Vinyl Division

20. Comparison Between Testing Methods Minimal standard deviation for 100 events In comparison, the MFEs are statistically equivalent 2011 SPE ANTEC Vinyl Division 20

21. In Conclusion This was a limited undergraduate research project and that more work would be helpful We would greatly appreciate your suggestions on additional areas to investigate in order to improve the value of this work Thank you 21 2011 SPE ANTEC Vinyl Division