No abstract

Flax fibre reinforced polyolefin composite is a great interest of today’s scientists. But the preparation of such composites with desired properties is a great challenge due to the dissimilar surface wettability (surface energy) of polyolefin and flax fibre. In this work, we have developed a linear low density polyethylene (LLDPE)/flax fibre based composite successfully. First, flax fibre is subjected to gamma radiation-assisted surface modification through covalent attachment of long chain hydrocarbon. Therefore, the surface wettability of flax fibre turns closer to that of LLDPE, and consequently a LLDPE/flax fibre composite with a strong interface is formed easily. Due to the designing of strong interface and consequently higher load transferring capability, properties are improved considerably. Young’s modulus and tensile strength values of composites with surface modified flax fibre become considerably higher compared to pure LLDPE and LLDPE/pure flax fibre composites. Strong reinforcement is reflected in the dynamic mechanical properties also. The highly improved dispersion and strong interfacial strength of LLDPE/modified flax fibre are observed in SEM (scanning electron microscopy). Thermal degradation temperatures of LLDPE and flax fibre are also improved in the composites.

The present work is an attempt to demonstrate that incorporation of small amount of zinc oxide nanorods enhances the β crystal percentage, which is essential for improvement in piezo-electric performance of the poly(vinylidene fluoride) (PVDF) fiber. The zinc oxide nanorods were synthesized with aspect ratio of 26 and uniformly dispersed in PVDF by melt compounding process. Those compounded polymers were melt spun and subsequently cold drawn to obtain composite filaments. The effect of nanostructure, loading amount, melt draw ratio, cold draw ratio, and drawing temperature was investigated. The incorporation of nanorods resulted in 14% increase in β phase crystal content compared to control PVDF filaments. The β phase crystal content has been analyzed using the wide-angle X ray diffraction and FTIR spectroscopy. This increase in β phase crystal content was 10% more compared to circular zinc oxide nanoparticle reinforced PVDF composite filament. There was no significant change in mechanical properties of the composite filaments compared to the control PVDF filament.

No abstract

Cotton fabric has been made electro‐conductive by electroless deposition of silver from its salt solution. Preparation process involved radical graft polymerization of glycidyl methacrylate monomer on plain woven cotton fabric using 10 kGy dose of electron beam irradiation, and then hydrazination of the epoxy ring of the monomer to introduce reducing agents into the fibre chemical structure. These reducing agents are sites for metal particle deposition. The chemical modifications were characterized by infrared spectroscopic studies. From X‐ray diffraction pattern analysis, the average size of these deposited silver metallic particles is 41 nm. These are observed as heterogeneous deposition on the fibre surface in scanning electron images. From thermogravimetric analysis, around 7.5% of the metal plated fabric weight is silver. The deposited silver nanoparticles make a conductive pathway through contact network, and this network brings a drop in average value of surface resistivity of the cotton fabric from 109 Ω/sq to 3.63 Ω/sq for the metallised fabric. Such prepared electro‐conductive fabric showed very good wash durability of electrical conductivity up to 15 washing cycles when carried out as per ISO‐105‐C10:2006 (E) test no. A (1) standard, indicating firm adherence of silver nanoparticles to the fabric surface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44576.