Investigation about the effect of previous impacts on the impact behavior of high impact polystyrene (HIPS)

• Published in: Journal of materials science 2004-04, Vol.39 (7), p.2543-2546
• Main Authors: SAHIN, T, SINMAZCELIK, T, ARICI, A
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Materials science; Mechanical properties; Organic polymers; Physicochemistry of polymers; Polystyrene resins; Properties and characterization
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1023/B:JMSC.0000020024.52958.13

It is known that micro voids form in the polymer during deformation and they can grow and coalesce to form larger cavities and crazes, which can be observed by the naked eye. Eventually fracture will occur, at least in a glassy polymer, by the breakdown of crazes into a crack. In these materials, the impact energy is most effectively dissipated by the formation of large craze envelopes at the crack tip. The dispersed impact modifier must arrest these crazes and must be sufficiently large so as not to be engulfed by the approaching craze. The rubber particle size must exceed the craze thickness and the interfacial adhesion must be sufficient to permit the effective transfer of stress to the rubber inclusion to blunt the craze. The required size is of the order of microns. The interparticle distance must be sufficiently small to prevent the occurrence of a catastrophic crack. HIPS polymer is used in mechanical engineering applications where machine parts are subjected to impact loading. In fact, most of the machine parts are subjected to impact loading repeatedly during their service life. This study is aimed to investigate the repeated impact behavior and the crack initiation and propagation mechanism of the HIPS material.