Rubber-toughened polymers have extensive applications due to excellent mechanical performances. However, the toughening mechanisms are not completely understood, as current study approaches are too localized for quantitative analysis and deviation from mechanical testing has rarely been taken into consideration.

In this study, Weibull statistics is applied to quantify the involvement of crazing and shear yielding mechanisms in poly(acrylonitrile butadiene styrene) (ABS) under tensile loading. Different loading rates were used to vary the involvement of each mechanism. In monotonic loading tests, the dominant deformation mechanism switches from crazing to shear yielding with the increase of crosshead speed. Crazing-dominant toughness values show narrow data scattering while those for shear yielding a broad distribution. The involvement of the deformation mechanisms can be varied through multi-stage loading at different crosshead speeds. Results from the study suggested that the Weibull analysis has the potential for quantifying the roles of various mechanisms in the deformation process.