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The research work aims to analyze the effect of graphene oxide (GO) distribution on the morphological, physical, static and dynamic mechanical properties of polyolefin matrices. Polar polymer namely maleic anhydride grafted polyethylene (MA-g-PE) is used as a compatilizer to incorporate GO into low density polyethylene (LDPE). Preparation of polyolefin nanocomposite is carried out by melt-mixing technique. According to ASTM standard, the specimens are prepared through compression molding technique. Mechanical properties of pure and graphene oxide filled polymers are analyzed through universal testing machine. Storage modulus and tan delta characteristics are analyzed through dynamic mechanical analyzer. A series of characterization methods like the X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscopic (TEM) were performed on the prepared nanocomposites. The effects of compatibilizer and grapheme oxide on polyolefin nanocomposites were investigated by dynamic mechanical analysis (DMA), tensile test and percentage elongation. The XRD results showed increase in intergallery spacing of nanosheets proving the formation of GO from flake graphite. TEM images prove the improved distribution of GO sheets into the polymer matrix in presence of compatibilizer. Compatiblized nanocomposites show significant enhancement in Tensile strength, modulus of elasticity, storage modulus and subsequent decrease in tan delta peak implying minimum heat buildup compared to control. Polar-polar interaction between GO and compatibilizer leads to improved distribution of the nanofiller in the base polymer matrices. This indeed enhances the technical properties of the polymer.

‘Nanocoolants’ offering extraordinary heat transport property demand new and exotic nanostructures as fillers that can display enhanced thermal conductivity and thermochemical stability for efficient thermal management operations. Herein we report for the first time, the processing of stable MAXene nanofluids using 2D MAXene nanosheets derived from the bulk nanolaminated Ti 3 SiC 2 MAX phase ternary carbides via shear induced micromechanical delamination technique. The beneficial multifunctional physical properties of MAXene colloid such as thermal conductivity, viscosity and lubrication effect are assessed and reported. An enhancement of thermal conductivity by ∼45% is achieved at 323 K with a loading of 0.25 Vol% MAXene nanosheets. Interestingly, MAXene nanofluids exhibit decreased viscosity than the basefluid revealing that it can act as ‘rheo-controlled’ nanofluid. It is a unique rheological behavior, not exist in many well established conventional ceramic nanofluids. In addition, MAXene nanofluids also offer lubricating property with very low coefficient of friction (COF) values (

A 2-dimensional ceramic nanostructure was successfully processed out of nanolamellar 312 MAX phase ternary carbide, titanium silicon carbide, Ti3SiC2 (TSC), via a simple shear-induced delamination technique. It has been explored as a functional nanofiller for obtaining chemically homogeneous, low-friction, self-lubricating epoxy nanocomposites. The structural characterization of the MAX phase Carbide Derived Ceramic Nanostructure (CDCN) was carried out using Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis. Subsequently, CDCN was mixed with Araldite CY 225 (DGEBA) at different percentages and thermally cured using Aradur HY 925 hardener at 130 °C to make epoxy–Ti3SiC2 nanocomposites. The effect of CDCN-nanofiller was studied on epoxy rheology, glass transition temperature (Tg), thermal stability, flexural and compressive strengths, microhardness, dry sliding wear and friction properties. It was found that, unlike other ceramic fillers, CDCN chemically interacts with epoxy and readily dispersed in a polymer matrix without any deleterious structural defects. It resulted in the formation of physico-chemically homogeneous microstructures. Epoxy composites prepared with CDCN filler attained 50% more mechanical strength and hardness. Wear analysis trends indicate Ti3SiC2 nano reinforcement possibly formed a lubricating tribo-chemical film that decreases the wear rate and coefficient of friction. This work is significant in such a way that a novel nanofiller has been identified from MAX phase carbide family which offers a self-lubricating interface and produces mechanically reliable, damage tolerant epoxy composite for state-of-the-art engineering applications.

Thermal, mechanical and tribological properties of a new ceramic–polymer nanocomposite in which polyaryletherketone (PAEK) polymer was reinforced with titanium silicon carbide (Ti3SiC2), a ceramic nanolaminate belonging to the MAX phase family (M is an early transition metal, A represents group IIIA or IVA element and X is either carbon and/or nitrogen) are reported for the first time. PAEK–Ti3SiC2 nanocomposites with varying volume fractions of Ti3SiC2 were processed by hot pressing. The effect of Ti3SiC2 on the thermal expansion, bulk hardness, mechanical strength, wear and friction properties was systematically analyzed and the results are discussed. The study confirms that the Ti3SiC2 controlled the high thermal expansion property of PAEK polymer. In addition to that, it enhanced the wear resistance and mechanical strength of PAEK without affecting its inherent low-friction characteristics.

Biopolymer-mediated sonochemical synthesis has been carried out for obtaining stable, nanocrystalline ZnO-biopolymer nanocomposite colloids to be applied on polymer foam and cotton fabrics to ultimately produce multifunctional, heath-care surface modifications. In situ nucleation and growth of nano-ZnO was achieved by ultrasonication at ∼ 60°C in aqueous biopolymer media prepared using starch, gelatin, chitosan, and agar. Phase analysis, structure–bonding characteristics, ZnO morphology, particle size distributions, rheology, and thermal decompositions were studied using XRD, FTIR, SEM/TEM, viscometer, and TG/DTA tools. Morphologically varied nanocrystalline ZnO of size ∼ 40 nm were synthesized. Biopolymers media resulted in stable ZnO colloids through steric stabilization. ZnO-biopolymer nanocomposites colloid was applied on polyurethane foams and cotton fabric substrates by dip coating. These coatings were examined for the UV photoactivity and resistance to fungi growth. A comparison has been made among the biopolymers. It is shown that the surface coatings of ZnO-biopolymer nanocomposites can produce anti-fungal, UV active polymer foams and fabrics. The study has significant relevance in automobile and hospital industries because such functionally modified polymer foams and cotton fabrics can be disinfected and refreshed just by periodic application of water-free, UV cleaning. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The present work encompasses the strategic design, synthesis and development of high energy field ZnO varistors. The key aspect of the study involves the chemical synthesis of ZnO based nanorod nanofillers by a pH selective precipitation and reflux method. High field varistors were developed out of these crystalline nanofillers by employing them as fillers to the micron sized commercial varistor powder. A systematic investigation of the microstructural changes of the nanofiller added varistor samples were carried out under step-sintering and the normal sintering conditions. Comparative studies were also performed with the nano and micro counterparts. The influence of nanofillers in the varistor powder packing, grain structure refinement, grain size reduction and on the I–V properties were analyzed under the step-sintering conditions. Based on the performance analysis, the current study foresees ample opportunities for miniaturizing varistors with at least half the size of currently available varistors.