Analysis of low temperature impact fracture data of thermoplastic polymers making use of an inverse methodology

In this work room and low temperature impact fracture data toughness of rubber modified polypropylene, polyethylene and rubber toughened polymethylmetacrylate have been assessed. In order to minimize the well-known dynamic effects a previously developed inverse methodology was used to treat force–time traces. Fracture parameters, such as KIQ and JC were estimated and the benefits of the inverse methodology were evaluated. The suitableness of energetic and force based toughness parameters for estimating a brittle to ductile transition was evaluated. The employment of the inverse methodology allowed us to infer the values of the crack tip loading rate, dK/dt, without the need of cushioning.