Study on the Improvement of Physical-Mechanical Characteristics in the EVA/PVC Blends Irradiation with Electron Beam in the Presence of Triallylisocyanurate (original) (raw)

Study on the improvement of physical-mechanical characteristic in the EVA/PVC blends irradiation with electron beam in the presence of triallylisocyanurate

Lucrarea prezintă un studiu privind îmbunătăţirea caracteristicilor fizicomecanice ale amestecurilor pe bază de elastomer etilenă propilenă terpolimer (EPDM) şi polietilenă de înaltă densitate (PEID), prin introducerea unor agenţi de compatibilizare sau iradiere cu electroni acceleraţi. Caracteristicile amestecurilor polimerice obţinute sunt aditive şi depind de cantitatea de EPDM şi PEID introduse în amestec. Utilizarea agenţilor de compatibilizare nu a condus la o îmbunatăţire semnificativă a caracteristicilor amestecurilor. Prin iradierea amestecurilor cu electroni acceleraţi la 5, 10, 15 si 20 Mrad, la creşterea dozei de iradiere, creşte modulul de elasticitate 100% şi alungirea la rupere, iar rezistenţa la sfâşiere prezintă un maxim urmat de o usoară scădere. The work presents a study on the improvement of physical-mechanical characteristics of blends containing EPDM and HDPE by introducing some compatibilizing agents or irradiating them with accelerated electrons. The characteristics of the obtained polymer blends are additive and dependent on the amounts of EPDM and HDPE involved. The use of compatibilizing agents has not led to a significant improvement of the charasteristics of the blends. Irradiating the blends with accelerated electrons at 5, 10, 15 and 20 Mrad, when the irradiation dose was increased there were an increase in the elastic modulus of 100 % and elongation at break and tear strength showed a maximum followed by a light decrease.

Electron beam irradiation induced compatibilization of immiscible polyethylene/ethylene vinyl acetate (PE/EVA) blends: Mechanical properties and morphology stability

Radiation Physics and Chemistry, 2017

Gel content, mechanical properties and morphology of immiscible PE/EVA blends irradiated by high energy electron beam were studied. The results of gel content measurements showed that the capability of cross-linking of the blend samples increased with an increase of the EVA composition. Also, the gel content for most compositions of the blends displayed a positive deviation from the additive rule. The results of mechanical properties showed that the tensile strength and elongation at break of the samples increased and decreased, respectively, with irradiation dose. On the other hand, the mechanical properties of the irradiated blends also depicted a positive deviation from additive rule contrary to the un-irradiated blends. A synergistic effect observed for the mechanical properties improvement of the irradiated blends and it was attributed to the probable formation of the PE-graft-EVA copolymers at the interface of the blends during the irradiation process. A theoretical analysis revealed that irradiation induced synergistic effect was more significant for EVA-rich blends with weaker interfacial interaction as compared to PE-rich blends. The morphological analysis indicated that the blend morphology was not affected obviously, whereas it was stabilized by irradiation.

Electron Beam Treatment for Enhancing the Compatibility, Thermal and Tensile Properties of LLDPE/PVA Blends: Part I, Effect of Irradiation Doses

In this work, the effect of electron beam radiation of linear low-density polyethylene (LLDPE)/ poly (vinyl alcohol) (PVA) blends are presented. The blends were prepared by melt mixing at 150 ºC at 60/40 (php/php), of LLDPE and PVA. Gel extraction, infrared spectroscopy diffraction scanning calorimetry, thermogravimetric, tensile properties and scanning electron microcopy had been used to investigate the effect of electron beam radiation on the properties of LLDPE/PVA blends. The exposure of these blends to 200 kGy dose of electron beam radiation increased the gel content, tensile properties (tensile strength and Young's modulus) and thermal stability due to the crosslinking formation, while, the melting temperature of LLDPE and PVA decreased as the PVA content was increased. The crosslink formation between LLDPE and PVA in the irradiated blends was demonstrated by the embedded PVA in LLDPE matrix as observed in optical images.

Effect of the electron beam irradiation on the properties of epoxidized natural rubber (ENR 50) compatibilized linear low-density polyethylene/soya powder blends

Journal of Applied Polymer Science, 2011

Linear low-density polyethylene/soya powder blends were prepared by using an internal mixer at 150 C. The soya powder content ranged from 5 to 40 wt %. Epoxidized natural rubber with 50 mol % epoxidation (ENR 50) was added as a compatibilizer. The blends were irradiated by electron beam (EB) at a constant dose of 30 kGy. The changes in gel fraction, tensile properties, morphological and thermal properties of the samples were investigated. The gel content increased after EB irradiation. However, the increment of gel content was hindered by increasing soya powder content. The tensile strength and Young's modulus of the blends were increased by EB whereas the elongation at break decreased. The tensile frac-ture surface also support the reduction of elongation at break by EB irradiation. Further analysis on the irradiated blends using Fourier transform infrared spectra indicated an increase of oxygenated product after undergoing EB irradiation. The differential scanning calorimetry result indicated that the melting temperature of the blends decreased after EB irradiation whereas the crystallinity increased. EB irradiation also enhanced the thermal stability of the blends as indicated by thermogravimetric analysis. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124: 5220-5228, 2012

Electron-beam irradiation of low density polyethylene/ethylene vinyl acetate blends

Journal of Polymer Engineering, 2013

The mechanical test showed that upon irradiation, the tensile strength (TS) values of the EVA/LDPE blends increased with the addition of EVA. A gradual increase in gel content (GC) and tensile strength (TS) with a concomitant decline in elongation at break (EB) and hot set (HS) were observed upon electron beam irradiation of the blends. The densities of all compounds were found to reduce with irradiation. The melt flow index test (MFI) results revealed that addition of ATH and MH reduced the flowability and addition of EVA improved the processability of the LDPE/EVA blend compounds. The TS of the LDPE/EVA blends deteriorated with the addition of flame retardants. The thermal stability and flame behavior of the halogen free flame retarded composites were studied by thermogravimetric analysis (TGA), limiting oxygen index (LOI), and cone calorimeter. The TGA results revealed that the decomposition temperatures of water evolved from the compounds incorporated with MH were significantly higher than that of ATH (i.e. 218e560 C versus 310e610 C). The minimum smoke density generation during the combustion obtained with 30% EVA content at both ATH and MH blends. The electrical test showed that the volume resistivity (VR) of the EVA/LDPE blends decreased with increase of EVA, ATH and MH contents, whereas, it declined with increasing irradiation dose. Consequently, this study demonstrated that addition of MH to the irradiated EVA/LDPE blends resulted higher thermal stability, better flammable retardancy, electrical and mechanical properties than addition ATH to the irradiated blends for wire and cable applications.

Modified effects of LDPE/EVA blends by electron beam irradiation

2007

The effect of electron beam irradiation on the properties of low density polyethylene (LDPE, LH0075) and ethylene vinyl acetate (EVA, with 18% VA) blends were investigated. The improvement of the measured gel content, stress at ultimate, strain at Auto breaks and transition temperatures (Tg, Tm) have confirmed the positive effects on blends but ineffective in density of blends.

The Effect of Electron Beam Irradiation on PE-g-MA Compatibilised Linear Low-density Polyethylene/Soya Powder Blends

In current investigation, the linear low-density polyethylene (LLDPE)/soya powder blends were compatibilised by polyethylene grafted maleic anhydride (PE-g-MA). The blends were prepared using internal mixer at a rotor speed of 50 rpm and temperature 150°C. The effect of LLDPE/soya powder composition and irradiation dose on the tensile properties of the blends was investigated. The results showed that an increase in soya powder content in the blends reduced the tensile strength and elongation at break. However, the tensile strength of LLDPE/soya powder blends was enhanced with the addition of the PEg -MA and further improved after irradiated with electron beam (EB) irradiation. The tensile strength of the blends increased with increasing irradiation dose, but the elongation at break decreased. From the morphological study done with scanning electron microscopy (SEM), the LLDPE formed continuous matrix after irradiation.

Effect of interfacial interaction on the mechanical properties of electron beam irradiated HDPE/STC blend

Journal of Applied Polymer Science, 2002

Some oxygen-containing groups (mainly CAO group) are introduced on the molecular chain of HDPE during electron beam irradiation in air. The affinity between HDPE and sericite-tridymite-cristobabite (STC), the dispersion of STC in HDPE matrix are improved owing to the polar groups introduced. By treating STC with amino-containing silane coupling agent, the interfacial adhesion between irradiated HDPE (e-HDPE) and treated STC (t-STC) is further improved, the mechanical properties of e-HDPE/t-STC blend are improved quite a lot. The experimental results show that due to the improvement of interfacial interaction, the interfacial phase can transmit the stress subjected to the HDPE matrix and make the matrix absorb energy by plastic yield or deformation; the impact strength of e-HDPE/t-STC blend is thus improved.