Effect of electron-beam and gamma-irradiation on physicochemical and mechanical properties of polypropylene syringes as a function of irradiation dose: Study under vacuum

Composites based on ethylene–propylene–diene terpolymer (EPDM), butyl/halobutyl rubber and nanosilica were prepared by melt mixing and subjected to different doses of electron beam irradiation. The effect of irradiation dose on the mechanical properties, morphology, glass transition temperature, thermal stability and water uptake was investigated. The efficiency of the crosslinking by electron beam irradiation was analyzed by Charlesby–Pinner parameter evaluation and crosslink density measurements. The scanning electron microscopy data showed a good dispersion of nanosilica in the rubber matrix. An improvement in hardness and 100% modulus was revealed by increasing irradiation dose up to 150 kGy. The interaction between polymer matrix and nanosilica was analyzed using the Kraus equation. Additionally, these results indicated that the mechanical properties, surface characteristics, and water uptake were dependent on crosslink characteristics.

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Changes in physicochemical and mechanical properties of electron-beam irradiated polypropylene syringes as a function of irradiation dose

Radiation Physics and Chemistry ◽

10.1016/j.radphyschem.2006.05.018 ◽

2007 ◽

Vol 76 (5) ◽

pp. 841-851 ◽

Cited By ~ 6

Author(s):

Athanasia T. Fintzou ◽

Anastasia V. Badeka ◽

Michael G. Kontominas ◽

Mario R. Stahl ◽

Kyriakos A. Riganakos

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Irradiation Dose

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Electrical conductivity and mechanical properties of conductive cotton fabrics

Journal of Industrial Textiles ◽

10.1177/1528083720984099 ◽

2021 ◽

pp. 152808372098409

Author(s):

RM Attia ◽

NM Yousif ◽

MH Zohdy

Keyword(s):

Mechanical Properties ◽

Gamma Irradiation ◽

Irradiation Dose ◽

Oxidative Polymerization ◽

Cotton Fabrics ◽

X Ray Diffraction ◽

Untreated Cotton ◽

Unit Space ◽

Hyperfine Splittings ◽

Curing Method

Functional electrically conductive fabric with acceptable mechanical properties, which could be applied in electromagnetic shielding, was developed. Conductive cotton fabrics (cotton/PANI, cotton/Mn, cotton/Cu, and cotton/Co) were prepared by in situ chemical oxidative polymerization for (cotton/PANI) and pad dry curing method was used for nanometals application. The Nano size of the metals and polyaniline inclusion were proven through both Dynamic Liquid Scattering (DLS) and X-ray diffraction (XRD) which showed an increase in crystallite density in unit space and the nanoparticles ranged from 100–200 nm. The effect of gamma irradiation on different treated cotton fabrics was investigated. The mechanical properties against irradiation dose showed an improvement up to 40 kGy, for all treated fabrics. On the other hand, Young’s modulus for untreated cotton recorded the lowest value, while cotton/Co recorded the highest one. Moreover, both AC (Alternating Current) and DC (Direct current) conductivities values can be calculated. In DC conductivity cotton/PANI was found to be more conducive than the remainder of the treated fabric by surface metallization with transition metals; while in AC conductivity cotton/Mn was found to be more conducive than the rest of the treated samples. The conductivity value increases by increasing the gamma irradiation dose for cotton/PANI fabric. Also, g-factor values can be estimated from ESR signals and vary from 0.009 up to 0.059 for conductive cotton fabrics; whilst cotton/Mn fabric has six hyperfine splittings, indicating that it is a paramagnetic element.

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Effect of electron beam irradiation on the thermal and mechanical properties of ethylene-vinyl acetate copolymer/polyamide blends

Polymers and Polymer Composites ◽

10.1177/0967391120930108 ◽

2020 ◽

pp. 096739112093010

Author(s):

Jawad Ahmed ◽

Yong Zhang

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Vinyl Acetate ◽

Irradiation Dose ◽

Ethylene Vinyl Acetate ◽

Cross Linking ◽

Thermal And Mechanical Properties ◽

Beam Irradiation ◽

Acetate Copolymer ◽

Ethylene Vinyl Acetate Copolymer

The effect of electron beam (e-beam) irradiation on the thermal and mechanical properties of ethylene-vinyl acetate copolymer/ternary polyamide (EVA/tPA) blends was studied. The e-beam irradiation was carried out over a range of dose from 50 kGy to 500 kGy with trimethylolpropane trimethacrylate (TMPTMA) and triallyl isocyanurate (TAIC) as cross-linking coagents. With increasing irradiation dose, the gel fraction of the EVA/tPA blends increased significantly. After irradiated by e-beam at 500 kGy, the insoluble fraction of EVA/tPA blends with 3 parts per hundred rubber TMPTMA increased from 28% to 86%. The tensile strength of EVA/tPA/TMPTMA-3 (70/30/3) considerably increased up to 172% with a value of 10.01 MPa at 500 kGy due to an increase in cross-linking compared to the EVA/tPA/TAIC-3 (70/30/3) blend. However, the melting temperature and crystallization peak temperature of EVA/tPA blends decreased with increasing irradiation dose. Thermogravimetric analysis demonstrated that the irradiation cross-linking could improve the thermal stability of the EVA/tPA blends. The degradation kinetics of the EVA/tPA blends at elevated temperatures were studied using the Kissinger, Flynn–Wall–Ozawa, and Friedman methods. Irradiation cross-linked EVA/tPA blends exhibited a remarkable improvement in their oil resistance, with the identified improvement being most prominent in the EVA/tPA/TMPTMA-3 blend.

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Effects of gamma irradiation on structural, thermal and mechanical properties of polyamide-11/halloysite nanotubes nanocomposites

Journal of Thermoplastic Composite Materials ◽

10.1177/08927057211031966 ◽

2021 ◽

pp. 089270572110319

Author(s):

Mohamed Sahnoune ◽

Mustapha Kaci ◽

Hélène Garay ◽

José-Marie Lopez-Cuesta ◽

Mohamed Mahlous

Keyword(s):

Mechanical Properties ◽

Gamma Irradiation ◽

Irradiation Dose ◽

Chain Scission ◽

Halloysite Nanotubes ◽

Thermal And Mechanical Properties ◽

Polyamide 11 ◽

Irradiation Test ◽

Twin Screw ◽

Low Irradiation

The effect of gamma irradiation on neat Polyamide-11 (PA11) and PA11 filled with 3 wt% of halloysite nanotubes (HNTs) was investigated at various doses up to 100 kGy in air and at room temperature. The irradiation test was conducted on sample films prepared by a twin-screw extruder in the first step then cast extrusion. The study showed the formation of a maximum of gel fraction up to 10 and 20 kGy for neat PA11 and PA11/HNTs, respectively. Furthermore, the results indicated the occurrence of crosslinking at low irradiation dose, whereas chain scission took place at higher ones. Additionally, the results revealed that the presence of HNTs limits the impacts of gamma irradiation through a barrier effect. An optimum irradiation dose was found for thermal and mechanical properties, corresponding to the dose for maximum gel formation. Moreover, experimental design was implemented to highlight the main incidences and interactions of both halloysite incorporation and radiation dose on some relevant effects of gamma irradiation.

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Influence of Electron Beam Irradiation on PP/Clay Nanocomposites Prepared by Melt Blending

e-Polymers ◽

10.1515/epoly.2007.7.1.1476 ◽

2007 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Shahryar Jafari Nejad ◽

Seyed Javad Ahmadi ◽

Hossein Abolghasemi ◽

Ahmad Mohaddespour

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Tensile Strength ◽

Electron Beam ◽

Young’S Modulus ◽

Irradiation Dose ◽

Young's Modulus ◽

Clay Nanocomposites ◽

Melt Blending ◽

Good Thermal Stability

AbstractIn this research, the melt blending technique was used to prepare various polypropylene (PP) based nanocomposites. A commercial organoclay (denoted 15A) served as the filler for PP matrix, and the maleic anhydride modified PP was used as compatibilizer. The specimens were subjected to electron beam (EB) irradiation. The purpose of the study focuses on the influences of EB irradiation on the thermal stability and mechanical properties of the nanocomposites. The morphology of the nanocomposites was studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD and SEM results showed that these nanocomposites are best described as intercalated systems. PP/Clay nanocomposites showed good thermal stability in the TGA analysis. TGA data at 500KGy showed that the EB irradiation has negative effect on thermal stability of the nanocomposites. Mechanical testing showed that the EB irradiation strongly influences the mechanical properties (tensile strength, Young’s modulus and hardness) of PP/Clay nanocomposites. The value of tensile strength decreases remarkably for all specimens with increasing irradiation dose up to about 550 KGy, but this reduction for nanocomposites with 3% clay is less than that of the pure PP/PP-g-MA blend. In higher irradiation doses, reduction in tensile strength of PP nanocomposites is less than that of the pure PP/PP-g-MA blend. Optimum irradiation dose of Young’s modulus for PP/Clay nanocomposites with 5% clay is 450 KGy. The hardness of the nanocomposites with 5% clay was found to decrease with increase in irradiation dose.

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Tensile Properties and Morphology of Irradiated EVA/ENR-50/Sepiolite Nanocomposites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.694.218 ◽

2016 ◽

Vol 694 ◽

pp. 218-222 ◽

Cited By ~ 2

Author(s):

Mohd Shahrulnizam Ahmad ◽

Zurina Mohamad ◽

Chantara Thevy Ratnam ◽

Amirah Kamal Rudin

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Natural Rubber ◽

Tensile Properties ◽

Vinyl Acetate ◽

Irradiation Dose ◽

Dose Range ◽

Epoxidized Natural Rubber ◽

Beam Radiation ◽

Electron Beam Radiation

The effects of sepiolite nanofiller addition and irradiation modification on the tensile properties of epoxidized natural rubber (ENR-50)/ehylene vinyl acetate (EVA)/Sepiolite nanocomposites were investigated. The ENR-50/EVA/Sepiolite was blended by mixing in a Brabender Plastigraph at 120 °C. The samples were irradiated by using electron beam at a dose range of 50 to 200 kGy. The effect on the tensile properties and morphology were investigated as a function of sepiolite content and irradiation dose. Electron beam radiation produced an irradiation-induced crosslinking and further enhanced mechanical properties of the nanocomposites. The tensile properties of irradiated ENR-50/EVA blend were improved by the addition of sepiolite at 4 phr.

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Different sterilization and disinfection methods used for human tendons – a systematic review using mechanical properties to evaluate tendon allografts

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04296-4 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Denes Farago ◽

Blanka Kozma ◽

Rita Maria Kiss

Keyword(s):

Mechanical Properties ◽

Carbon Dioxide ◽

Electron Beam ◽

Supercritical Carbon Dioxide ◽

Gamma Irradiation ◽

Modulus Of Elasticity ◽

Failure Load ◽

Biomechanical Properties ◽

Sterilization Method ◽

Supercritical Carbon

Abstract Background It is important to know the biomechanical properties of an allograft. This is because when looking to do a transplant of a tendon, the tendon must have very similar biomechanical properties to the original tendon. To use tendon allografts, it is critical to properly sterilize the tendon before implantation. In past decades, several sterilization procedures have been used. This study aimed to systematically evaluate the existing literature to compare the values of failure load/ultimate strength and Young’s modulus of elasticity of different sterilization methods on commonly used tendon allografts. Five major scientific literature databases (Web of Science, Science Direct, Scopus, PLOS ONE, Hindawi) and additional sources were used. Results Studies used had to show a particular sterilization method. Studies were identified to meet the following inclusion criteria: is a controlled laboratory study, gamma irradiation (dose reported), and other sterilization methods. Search for publications dated between 1991 and March 31st, 2020. The database search and additional sources resulted in 284 records. Two hundred thirty records eliminated during the screening for various reasons. The number of articles used in the final synthesis was 54. Conclusions Identified sterilization methods (gamma irradiation, ethylene oxid, supercritical carbon dioxide (SCCO2), BioCleanse, Electron Beam) are offered as a catalog of potential methods. As a result of the broadness of the present research, it provides an overview of sterilization methods and their effect on the mechanical properties (failure load and Young’s modulus of elasticity) of tendons. It does not stand for the state-of-the-art of any single process. Based on a systematic literature review, we recommend freezing and gamma irradiation or electron beam at 14.8–28.5 kGy. These methods are effective at keeping or improving the mechanical properties, while fully sterilizing the inside and the outside of the tendon. Other sterilization method (ethylene oxide, supercritical carbon dioxide (SCCO2), BioCleanse) deteriorated the mechanical properties. These methods are not recommended.

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