Fracture toughness of gamma irradiated polycarbonate sheet using the essential work of fracture

Weber, Ricardo Pondé; Monteiro, Sérgio Neves; Suarez, João Carlos Miguez; Oliveira, Celio Jorge Vasques de

doi:10.1016/j.polymertesting.2016.11.021

Cited by 11 publications

(8 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…in Fig. 9, which is consistent with the results obtained in mechanical tests of EWF 19,26 . Figure 10 shows the fracture morphology observed for samples subjected to the EWF test and exposed to UV radiation for 300 hours and 600 hours.…”

Section: Tensile Testssupporting

confidence: 91%

“…By contrast, a smaller reduction in the tensile strength of 9-10 % is noticed for both UV time exposures. The elongation reduction is attributed to a smaller molecular weight, as found in gamma irradiated samples 19,31,8,32 , which reduces the plastic deformation capacity of the material. In the case of tensile strength, the relatively small reduction might be assigned to the decrease in PC molecular length due to chain scission 12 .…”

Section: Tensile Testsmentioning

confidence: 92%

“…Among ductile polymers, polycarbonate (PC) tends to show brittle transition in association with specimens presenting small thickness 13,14 , under notched conditions 15,16 , high strain rate 17 and subjected to gamma radiation 18,19 . In fact, a ductilebrittle transition in PC is well recognized 14,20 .…”

Section: (B)mentioning

confidence: 99%

“…In fact, a ductilebrittle transition in PC is well recognized 14,20 . Moreover, its fracture toughness could be determined by the EWF method for possible engineering applications, such as the exposure to gamma radiation in nuclear track detection and medical instruments sterilization 19 . Ultraviolet irradiation (UV) is also used for sterilization process because, unlike the ethylene oxide process (ETO), it leaves no residual toxic products.…”

Section: (B)mentioning

confidence: 99%

“…Indeed, 300 hours and 600 hours of exposure caused W e reductions of 39 % and 45 %, respectively. These reductions are probably due to scission of the polymer chains and an associated decrease in the plastic deformation capacity 19 . As compared with the tensile test results, Fig.…”

Section: Ewf Testsmentioning

confidence: 99%

See 4 more Smart Citations

Evaluation of Fracture Toughness of Ultraviolet-Irradiated Polycarbonate Using the Essential Work of Fracture Method

et al. 2018

View full text Add to dashboard Cite

The essential work of fracture (EWF) method provides useful parameters to characterize the fracture toughness of polymers exposed to degrading environments under conditions associated with plane-stress state of failure. Exposure of polymeric engineering materials to ultraviolet (UV) radiation may produce macromolecular changes that impair their fracture toughness. In the present work, for the first time, the EWF method applying a double edge notched tensile specimen was used to quantify the fracture toughness behavior of polycarbonate (PC) exposed to different, 300 h and 600 h, UV irradiation times. In addition, molar weight Mn Q V determination, differential scanning calorimetry (DSC), Fourier transformed infrared spectroscopy (FTIR) and tensile tests were also investigated for non-irradiated and UV irradiated PC. The EWF results and scanning electron microscopy analysis revealed a significant reduction (39 % for 300h and 45 % for 600h of UV exposure) in fracture toughness associated with scission of the macromolecular chains. Other investigated properties, such as Mn , glass transition temperature, oxidation index and tensile strength, despite decreasing with UV exposure, did not show conclusive values.

show abstract

Section: Tensile Testssupporting

confidence: 91%