Effects of radiation type and dose on the properties of selected polymers

Abstract

Using ionizing radiation to sterilize medical and health care products is a widespread and well established approach, as products can be treated in their final shipping container without any residuals. During irradiation, the product materials will undergo some changes due to the absorbed energy, which have to be assessed during product qualification in order to specify a maximum allowable dose for the product. However, there is a lack of a systematic approach studying polymers in regard to dose ranges encountered and all types of ionizing radiation. Therefore, the aim of this work was to investigate the influence of radiation dose and source on the resulting properties of various polymers, which were already brought into final shape via injection molding, and to compare these effects found in the mechanical and rheological properties as well as their appearance. We found, that the mechanical properties of most investigated polymers are not influenced, except for polypropylene, but that yellowing was a pronounced effect in all the cases. The differences in polymer properties due to the radiation sources are small, only some materials exhibit more degradation by gamma irradiation due to the lower dose rate applied in comparison to x‐ray and e‐beam irradiation.

Radiation-Based Crosslinking Technique for Enhanced Thermal and Mechanical Properties of HDPE/EVA/PU Blends

“…HDPE has the characteristic that when tertiary carbon atoms in the branch chain lose hydrogen, they generate radicals that are easily attacked by external free radicals and stabilized. Thus, crosslinking occurs readily due to easy radical generation [ 28 , 29 ].…”

The effects of the cross‐linking mechanism of low doses of gamma irradiation on the mechanical, thermal, and viscoelastic properties of the natural rubber latex/poly(styrene‐block‐isoprene‐block‐styrene) block copolymer blend

“…Ionizing radiation is a green technique to modify the chemical bonds of polymers through a spontaneous ionizing process. [15] A radiation source such as an electron beam, gamma rays, or X-rays [16] act as the initiator to generate free radicals, inducing some chemical reactions, resulting in either branching, cross-linking, or chain scission in the system. Since the reactions coexist and compete with each other, the predominating reaction is controlled by the dose rate, absorbed dose, and temperature.…”

Radiation effects on Kevlar fibers through high energy electron beam

“…Electron beam radiation technology has been widely used in many fields owing to its advantages of stability, energy savings, and lack of pollution. [16][17][18][19] High-energy electron beams can ionize or excite a material, leading to the formation of free radicals and triggering reactions. [20][21][22][23] In this study, Kevlar fibers were irradiated at up to 2500 kGy using a 10 MeV electron accelerator in an air environment, and the radiation stability of the Kevlar fibers was evaluated by comprehensive analysis.…”