Electron Beam Irradiated Polymers Research Articles

Optical properties of sub-surface silver nanoparticulate films on 8 MeV electron beam irradiated polymer blends

Results of the investigations carried out on the optical properties of silver nanoparticulate films deposited on the electron beam irradiated blends of polystyrene (PS) and poly(4-vinylpyridine) (P4VP) are reported. Sub-surface silver particulate films are deposited at a constant deposition rate of 0.4 nm/s on irradiated blends held at 455 K in a vacuum of 8 × 10−6 torr. The optical absorption studies indicate that the morphology of the nanoparticulate films can be tuned by electron beam irradiation of polymer blends. The change observed due to irradiation is attributed to the formation of free radicals, thereby altering the polymer–metal interaction. A shift in the plasmon resonance peak towards longer wavelengths is observed for 50 nm thick silver particulate films deposited on softened 8 MeV electron irradiated P4VP as compared to unirradiated P4VP. The shift is more in the case of P4VP than for PS, possibly due to the combined effect of free radicals produced by irradiation and the lone pair of electrons present in P4VP in enhancing the metal–polymer interaction. The saturation of free radicals takes place in P4VP at doses higher than 25 kGy. Further, the results also indicate that the free radical creation due to irradiation is more in PS than in P4VP, as the saturation takes place at lower doses in a PS/P4VP blend as compared to P4VP and in a blend with higher PS content. X-ray diffraction studies on silver films deposited on unirradiated and irradiated, softened polystyrene substrates do not show any significant change due to irradiation.

Potential Of Electron Beam Irradiated HDPE/EPR Blend As Shoes Sole

This study focuses on the mechanical effect of different composition of polymer blend. Polymer blend of high density polyethylene (HDPE) and ethylene propylene rubber (EPR) were selected and varied by three different compositions which are 70:30, 50:50 and 30:70. HDPE-EPR blend is believed to be the best material for sole shoe. In which, HDPE has good flexibility while, EPR can maintain optimum performance at high and low temperature as well as provide better gripping characteristic that suits for insole and outsole sport shoe. On the other hand, the time efficiency of electron beam radiation on these polymer blends helps in improving the croslinking of HDPE-EPR blend. The aim of this paper was to find the optimum composition of electron beam irradiated polymer blends for sole shoes especially in sports application. These irradiated polymer blends were produced by melt blending, underwent compression moulding and then were irradiated by electron beam at 100 kGy/s. Mechanical test of tensile and hardness test were investigated and the morphology of the failure fracture was analysed by field emission scanning electron microscopy (FESEM). The polymer blend with 70% of HDPE and 30% of EPR showed the optimum result of tensile strength, tensile modulus and hardness as well as ductile failure image.

Contact angle and surface free energy of electron-beam irradiated polymer composites

The effects of the electron radiation dose and of compatibilizers on the contact angle and surface free energy (SFE) of the composites made of low-density polyethylene (PE-LD), high-density polyethylene (PE-HD), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) were studied. Use of the high-energy electron radiation with doses up to 300 kGy and of compatibilizers was done to reach better mechanical and adhesion properties of the composites studied and, at the same time, to investigate the possibility of applying of this technique in the processes of polymeric materials recycling. The compatibilizers were the styrene-ethylene/butylene-styrene elastomer grafted with maleic anhydride (SEBS-g-MA), added at the amounts of 5, 10 or 15 wt. %, and trimethylol propane trimethylacrylate (TMPTA), added at the amounts of 1,2 or 3 wt. %. The effects, discussed in the present article, are: enhancement of wettability and increase in SFE of the composites studied. It was found that the contact angle steadily decreased and SFE of the composites increased with the rising dose of the electron radiation and that TMPTA intensified these tendencies.