Mechanical Properties and fracture surface morphologies in rubber - PMMA composites

Abstract

Correlations between mechanical properties and microscopic features were investigated using both unnotched and notched specimens of rubber-toughened PMMA materials in very low to medium range of cross head speeds. It is found that: (1) significant difference in fracture surface morphologies between pure PMMA and rubber-toughened PMMA of unnotched specimens can be correlated with their difference in modes of failure; and variation of degree of roughness in rubber toughened PMMA can be correlated with variation of Young's modulus which is affected by rubber content; (2) decreasing trend of crack initiation region with increasing speed in notched specimens correlates with that of fracture elongation; and decreasing trend of stress whitening zone in notched specimens with both increasing speed and decreasing rubber content correlates with that of calculated plastic zone and the trend correlates also with that in modulus of toughness.