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For further developing of a standardized crack resistance curve (R-curve)routine for thermoplastic polymer materials, the kinetics of the crack propagation underimpact loading conditions must be universally clarified. Here, the instrumented Charpy impacttest is used for the determination of fracture mechanics parameters. In this connection,methodical investigations have shown that only by use of the stop block method andmultiple-specimen technique it is possible to determine crack resistance curves that correspondto homogenous kinetics of crack propagation. Other methods of R-curve determinationsuch as the low-blow technique are normally not suitable for polymers due to the timedependentmechanical properties of these materials. Typically, the crack-tip-opening displacementrate as resistance against the intrinsic rate of fracture mechanics parametersconverges rapidly to a matrix-specific threshold value corresponding to (quasi) steadystatestable crack propagation (an equilibrium state) after crack initiation and nonstationarystable crack propagation. This behaviour forms a basic to describe the relationshipbetween the loading parameters such as J-integral or CTOD and the stable crackgrowth theoretically.