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LaPO4 ceramic colorants were processed in the vibrant shades of green and brick red, and subsequently embedded in polymer resins for the fabrication of heat management coatings. The IR/UV shielding characteristics of these ceramic colorants and polymer coatings were analysed and it was found that the ceramic dispersoids enhance the IR reflectance quality of polymer resins by 20 to 25 times. The nano ceramic green colorant-reinforced polymer coating on glass panels offers the stringent property, i. e., optical transparency and heat reflectance combined, when exposed to direct sunlight. Other photophysical properties were also studied and analysed. The brick red colorant entrenched resin coating on metal substrate offered heat reflectance and corrosion resistance characteristics. XPS studies provided the chemical environment of the systems. Surface morphology, crystallinity and particle size of the products were investigated using SEM, TEM, XRD and DLS techniques. The polymer resin coating of these ceramic colorants offers thermal stability and colorfastness properties.

Thermo-mechanically durable industrial polymer nanocomposites have great demand as structural components. In this work, highly competent filler design is processed via nano-modified of micronic SiO2/Al2O3 particulate ceramics and studied its influence on the rheology, glass transition temperature, composite microstructure, thermal conductivity, mechanical strength, micro hardness, and tribology properties. Composites were fabricated with different proportions of nano-modified micro-composite fillers in epoxy matrix at as much possible filler loadings. Results revealed that nano-modified SiO2/Al2O3 micro-composite fillers enhanced inter-particle network and offer benefits like homogeneous microstructures and increased thermal conductivity. Epoxy composites attained thermal conductivity of 0.8 W/mK at 46% filler loading. Mechanical strength and bulk hardness were reached to higher values on the incorporation of nano-modified fillers. Tribology study revealed an increased specific wear rate and decreased friction coefficient in such fillers. The study is significant in a way that the design of nano-modified mixed-matrix micro-composite fillers are effective where a high loading is much easier, which is critical for achieving desired thermal and mechanical properties for any engineering applications. Copyright © 2016 John Wiley & Sons, Ltd.

Nano/micro ceramic-filled epoxy composite materials have been processed with various percentage additions of SiO2, Al2O3 ceramic fillers as reinforcements selected from the nano and micro origin sources. Different types of filler combinations, viz. only nano, only micro, nano/micro, and micro/micro particles, were designed to investigate their influence on the thermal expansion, thermal conductivity, and dielectric properties of epoxy polymers. Thermal expansion studies were conducted using thermomechanical analysis that revealed a two-step expansion pattern consecutively before and after vitreous transition temperatures. The presence of micro fillers have shown vitreous transition temperature in the range 70–80°C compared with that of nano structured composites in which the same was observed as ~90°C. Similarly, the bulk thermal conductivity is found to increase with increasing percentage of micron-size Al2O3. It was established that the addition of micro fillers lead to epoxy composite materials that exhibited lower thermal expansion and higher thermal conductivity compared with nano fillers. Moreover, nano fillers have a significantly decisive role in having low bulk dielectric permittivity. In this study, epoxy composites with a thermal expansion coefficient of 2.5 × 10−5/K, thermal conductivity of 1.18 W/m · K and dielectric permittivity in the range 4–5 at 1 kHz have been obtained. The study confirms that although the micro fillers seem to exhibit good thermal conductivity and low expansion coefficient, the nano-size ceramic fillers are candidate as cofillers for low dielectric permittivity. However, a suitable proportion of nano/micro-mixed fillers is necessary for achieving epoxy composites with promising thermal conductivity, controlled coefficient of thermal expansion and dielectric permittivity. Copyright © 2013 John Wiley & Sons, Ltd.

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

A method for the preparation of alumina–aluminum titanate (AT) composites, which can be sintered to high density with a fine-grained microstructure at