The effect of gamma irradiation in air and inert atmosphere on structure and properties of unfilled or glass fibre-reinforced polyamide 6 (original) (raw)
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Journal of Applied Polymer Science, 2005
Compressed molded waste poly(propylene) was reinforced with short carbon and/or glass fibers for investigation. The prepared composites were ␥-irradiated to estimate the role of the ionizing radiation as a compatibilizing agent. TGA and DSC were used to investigate the influence of exposure dose and the incorporation of short fibers on the thermal parameters of the prepared composites. The mechanical properties of different composites were also studied. It was observed that the mechanical and thermal parameters were highly affected by the kind of incorporated fibers and ␥-irradiation. The structural and morphological studies were made by means of XRD and SEM to investigate the structure change caused by the incorporation of short fibers and exposure to ␥-irradiation. The results show that the irradiation of carbon fiber-containing composite magnified its thermal stability and its tensile strength.
Composites Science and Technology, 2019
Polyamide 66 (PA 66) and short glass fiber reinforced versions of PA 66 are widely used for solar-thermal applications, in which thermal and environmental loading of components is from high importance. In this study, the influence of crosslinking via electronic beam irradiation on the morphology and mechanical behavior of unreinforced PA 66 and two types of short glass fiber reinforced PA 66 (30 wt % glass fiber content, 35 wt % glass fiber content) was investigated. In total, five different electronic beam irradiation doses in the range of 0 and 200 kGy were applied. Besides experiments with unconditioned specimens, also preconditioned specimens saturated with water at 80 • C for seven days were investigated. It was found that irradiation causes a shift to lower melting temperatures and lower melting enthalpies, while simultaneously leading to higher glass transition temperatures (T G), increasing small strain modulus values and higher tensile strengths. Also, as expected, preconditioning samples in water at 80 • C to water uptake saturation leads to a shift to lower T G values ('plasticization' effect). In terms of tensile behavior at room temperature, water saturated specimens (being above T G at room temperature) exhibited lower modulus and tensile strength values compared to quasi-dry specimens (being below T G at room temperature).