This work focuses on the effect of electron beam irradiation on the physico‐mechanical, dynamic mechanical and dielectric properties of blends based on ethylene octene copolymer (EOC) and poly dimethyl siloxane (PDMS) rubber. It is found that electron beam irradiation caused considerable improvement in the physico‐mechanical properties; the tensile strength was enhanced by nearly 35% for 70:30 EOC:PDMS blend. Phase morphology of the blends analyzed before irradiation by scanning electron microscopy (SEM) exhibited droplet/matrix morphology with sizes of the PDMS rubber domain varying from 0.55 µm to 0.47 µm as the amount of PDMS rubber decreased from 30 wt% to 10 wt%. This reduction in the PDMS rubber domain has been correlated with the physico‐mechanical properties of the blends. Further, the dynamic mechanical properties and creep behavior of these EOC:PDMS blends before and after irradiation has been studied. It is inferred that the 70:30 blend after radiation crosslinking shows a 17% decrease in the creep compliance, i.e. higher creep resistance compared to neat blends. All the radiation crosslinked blends exhibited lower dielectric constant, lower dielectric loss and higher electrical resistivity as compared to the virgin blends which makes it suitable for cable insulating application. Copyright © 2016 John Wiley & Sons, Ltd.

A novel thermoplastic vulcanizate (TPV) based on the blends of ethylene vinyl acetate/thermoplastic polyurethane (EVA/ TPU) at various blend ratios has been developed via dynamic vulcanization at 180 8C using di-(2-tert-butyl peroxy isopropyl) benzene (DTBPIB) peroxide as the cross-linking agent. Modification of the EVA/TPU blends via dynamic crosslinking significantly improves the tensile strength and modulus of the system and the improvement is more significant for EVA/TPU 50/50 and 60/40 blends. AFM study shows that crosslinked EVA particles are dispersed in the continuous TPU matrix and the dispersed EVA domain sizes are relatively smaller in EVA/TPU 50/50 and 60/40 blends leading to good mechanical properties. FTIR spectroscopy has been used to characterize the specific chemical changes occurring due to dynamic vulcanization. This TPV has excellent retention of physicomechanical properties even after reprocessing twice and the blends also have very good thermal resistance as indicated by aging study. The samples were found to exhibit remarkable improvement in oil resistance property as compared to their uncrosslinked counterpart. The creep behavior of the blends significantly improves after dynamic crosslinking and blends with higher TPU content show better creep resistance. Volume resistivity of all the peroxide vulcanized blends is in the range of 10 13 ohm cm, which is suitable for cable sheathing application.

A new experimental approach is described for obtaining a quantitative measure of the wettability of filaments. This technique is based on the spontaneous capillary rise of liquid between two filament surfaces held in an adjustable v-shaped arrangement. No contact angle measurements are necessary, all information being obtained from simple length readings. The apparatus allows a filament sample to be tested in different liquids and conditioned without being removed from the test mounting. Results are expressed in terms of the free energy of wetting. Some dependency on filament spacing at the liquid source level has been observed, but none connected with the angle between them.

The present work provides an extensive insight on effect of hybrid nanofillers and its structure-property relationship in nanocomposites based on bromobutyl rubber (BIIR)/ polyepichlorohydrin rubber (CO) blends. TEM photomicrographs reveal high degrees of dispersion of nanoclay with the formation of hybrid nanostructures. Rheological behavior of the nanocomposites displays shear thinning nature and significant reduction of die swell (up to 13% reduction) is observed with increase in the dosage of nanoclay. The addition of the nanoclay drastically reduces the air permeability up to 17%, increases electrical conductivity and thermal conductivity of the rubber nanocomposites. Adhesion of rubber to the fabric ply is found to be good in the nanocomposite having a lower dosage of nanoclay. These unique attributes were found to stem from the fundamental viscoelastic characteristics i.e., increase in the entanglement density due to the hybrid nanostructures. The development of hybrid nanostructures and its significant contribution to the improvements of properties are schematically explained. Rubber formulations with such suitably tailor nanostructures will find their applications for next generation rubber based industrial products. 23to the low free path of the phonon and frequent phonon scattering effect at the rubber interface, the net thermal conductivity of B 90 H 10 CB 50 NC 0 is less. Scheme 5 explains the effect of hybrid nanostructure in enhancing the thermal conductivity of the nanocomposites. The dispersed hybrid nanostructures bridges between the BIIR-CO interface and acts as an extended path for the phonons to travel. The extended mean free path of phonons have now become to (λ+x) and (λ+y) from λ before it gets scattered. The increase in the mean free path corresponds to the increase in the thermal conductivity of the nanocomposites. However, relative decrease in the thermal conductivity of B 90 H 10 CB 50 NC 10 with increase in the temperature corresponds to the increase in the number of structural defects in the nanocomposites at higher temperatures. 32Scheme 5: Increase in the mean free path due to the formation of hybrid nanostructure in BIIR-CO nanocomposites 4.7. Adhesion Strength.Adhesion between the components is a basic requisite of any composite product when it is subjected to dynamic applications. The effect of nanoclay on the adhesion of the nanocomposites with neighboring fabric compound were analyzed and shown in Figure

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