Premium
Influence of mineral oils on polystyrene fracture
Author(s) -
Paredes Edgar,
Bustamante Armando,
Rivas Luciano
Publication year - 1983
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.760230904
Subject(s) - materials science , composite material , polystyrene , fracture (geology) , breakage , viscosity , polymer , surface tension , volume fraction , ultimate tensile strength , fibril , physics , quantum mechanics , biology , genetics
Polystyrene specimens coated with mineral oils of different viscosities were tested in tension. It was found that craze initiation and tensile fracture stresses, and also the breaking energy decreased with decreasing oil viscosity, all being lower than for specimens tested in air. Crazes formed in oil showed a lower fibril volume fraction and thicker fibrils than air crazes. The most striking difference in the fracture patterns was found in the initiation regions, where a globular morphology appears as a result of fibrils breakage at the stages of slow propagation, these globules becoming bigger with decreasing viscosity of the oil environment. Since the polymer‐oil interfacial tensions are similar for the different oils, the trends in mechanical properties and craze and fracture morphologies cannot be attributed to a surface energy effect, but to plasticization because the deterioration in the polymer properties and the increasing craze fibrils thickness go along with the plasticizing ability of the oils.