Semi-finished products Plastic granules Special compounds

High energy radiationThe radiation absorbed dose is defined as the amountof energy absorbed per unit mass.SI unit is [J/ kg] or [Gy]; the old unit was [Rad], abbreviated“rd”.The conversion is the following:1 J / kg = 1 Gy = 100 rad.The absorbed dose rate indicates how fast the energyis absorbed [Gy/ s].Between a sterilization done either by electron beam,or X-ray or gamma-ray, there are no direct differences,concerning their influence on the plastic propertiesvariations, of course when these procedures havegot the same absorbed dose and dose absorbed rate.Anyway, there is an indirect difference between asterilization made with gamma irradiation and onemade with an electron beam. In fact in both proceduresan oxidative degradation takes place.However with the same absorbed dose and doseabsorbed rate, this degradation is with an electronbeam many times higher than with a gamma irradiation.PFMFPIEP unsaturatedPEEK amorphousPEIPAIPEEK semi-crystallinePUR thermosetPPSPVDFPELDPETPESPCPVCABSPSUPBTUHMWPEPA 11HD PEPA 6; PA 12PMMAPOM CPTFEPPSpalte 110 100 1.000 10.000Threshold limit dose, down to an elongation at break decrement of –25% [kGy]Figure 7: relative resistance of the standard plasticsRelative resistance against high energy radiationFigure 7 shows the pure radiation resistance of plastics.As property limit value, an elongation at breakdecrement of –25% from the initial value is used.Looking at this graphic is observable, that thermosettingplastic are more resistant than the thermoplastic,and aromatic polymers are more resistant than thealiphatic ones. Plastics with low density have got ahigher resistance.Rating of ZEDEX ® polymers resistanceagainst radiationsZX-100K is relatively resistant to high-energyradiation. A first strong degradation occurs with anabsorbed dose of 1000 kGy (10 kGy / h; 1 meV gammaray, source: Cobalt-60).ZX-410 has got a high resistance to gamma-rays andbeta-rays radiations. After a radiation exposure of15000 kGy (2 MeV electron beam; 5 kGy / s), ZX-410has still got 90 % of its tensile strength.ZX-324V1T is to alpha, beta and gamma rays veryresistant. A gamma-ray absorbed dose of 10 000 kGycauses nearly no damage.ZX-324ZX-410ZX-324V2TZX-324VMTZX-324V11TZX-750V5TZX-750V5KFZX-410V7TZX-100KZX-100MTZX-530KF15ZX-530ZX-530EL3ZX-100EL55/63ZX-530CD3ZX-550ZX-550PVSterilization dose (lethal for microorganisms)10 100 1.000 10.000Threshold limit dose, down to an elongation at break decrement of -25% [kGy]Figure 8: relative resistance of the ZEDEX ® plasticsReference: [1] WikipediaZEDEX ® basic types ZEDEX ® families Post heattreatmentMachiningShippingoverviewSterilizationChemicalresistance79