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Study of crystallization behaviour of electron beam irradiated polypropylene and high-density polyethylene.

ABSTRACT: The influence of electron-beam irradiation on polypropylene (PP) and high-density polyethylene (HDPE) was investigated with a focus on crystallization. A high-temperature (200°C) creep test revealed that the HDPE gradually increased cross-linking density in the range 30-120 kGy, while the PP underwent a chain scission which was quantitatively evaluated by gel permeation chromatography. The mechanical properties were measured in the range -150 to 200°C by a dynamic mechanical analysis. A small presence of C=C and C=O bonds was found in the irradiated PP by a Fourier transform infrared spectroscopy. Crystallization kinetics measured by differential scanning calorimetry and hot-stage optical microscopy results were influenced tremendously by irradiation for HDPE and to a lesser extent for PP. Irradiation caused a decrease in both the number of nucleation centres and the growth rate of individual spherulites. Crystallization was analysed in detail with the help of Hoffman-Lauritzen, Avrami and Arrhenius equations. Interestingly an increasing β-crystal formation with an increasing irradiation level was discovered for PP by X-ray diffraction. A generation of defects in the crystalline structure owing to irradiation was discussed.

SUBMITTER: Svoboda P

PROVIDER: S-EPMC8101015 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Thermomechanical Properties of Virgin and Recycled Polypropylene-High-Density Polyethylene Blends.

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Trapped radical behavior of electron beam irradiated polytetrafluoroethylene fine powder at various temperatures.

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| S-EPMC8149384 | biostudies-literature

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