Velram Balaji Mohan

Hybridization of graphene-reinforced two polymer nanocomposites

ABSTRACT This article focuses on the hybridization of thermoplastic polymer matrices with conducting polymers and graphene derivatives. Polypropylene (PP), polymethylmethacrylate (PMMA) and polyoxymethylene (POM) were used as primary polymer matrices and polypyrrole (PPY) and polyaniline (PANI) as secondary conducting polymers. Highly conductive-reduced graphene oxide (rGO) and graphene (G) have been used as reinforcements. A Taguchi analysis has been performed for the blends to find the optimal combination of the blends with respect to electrical conductivity (σ) and mechanical properties. Both electrical and mechanical properties were improved by the hybridization process. The maximum electrical conductivity of 0.85 S.cm−1 has been acquired with POM/PPY/G blend with 3 wt.% and 5 wt.% of PPY and graphene loading, respectively. The mechanical properties have been found to improve with all the blends but, PP/PPY/G blend with 3 wt.% and 6 wt.% of PPY and graphene loading displays overall better properties in comparison with other blends.

Optimisation of hybridisation effect in graphene reinforced polymer nanocomposites

This article focuses on the optimisation of electrical and mechanical properties of hybrid blends of polyoxymethylene (POM) as primary thermoplastic matrix, polypyrrole (PPY) as secondary conducting polymer and graphene (G) as reinforcement. An initial Taguchi analysis was performed with a focus on improving electrical conductivity (σ) and tensile strength. A mixture analysis using ‘simplex’ statistical design was applied to develop an experimental subset that identified an optimal combination in weight-percentage. Both electrical and mechanical properties were improved by the addition of PPY and graphene particles due to hybridisation mechanism as well as double percolation threshold. The maximum electrical conductivity of 0.95 S cm−1 was achieved with POM reinforced with 3 wt.% of G and 2.5 wt.% of PPY loading. The mechanical properties were found to be increased with increase in addition of both G and PPY.

Correction to: Quantification and analysis of Raman spectra of graphene materials

In the original version of this article Michel Nieuwoudt was listed as second author in the author group.

Graphene: A promising nano-reinforcement for functional composite materials

The proof of three different nova or supernova debris streams impacting the planet and causing global warming is shown by studying the effects, locations, and timings for specific thermal and destructive events in the northern and southern hemisphere. Global warming is not manmade and reducing fossil fuel emissions is not the solution to protect the populations of different countries from catastrophic events due to increased thermal energy storage for the planet. The burning of atoms of incoming debris streams from exploding stars produces energy and greenhouse gases that cause the average temperature of our planet to increase. India is the current hotspot due to the location of the deflected western terminus of SN 1006. Hotspots occur that are not as obvious as the India case, but melting sea ice exposes the debris streams’ hotspot activities. The incoming momentum of a debris stream can displace a large amount of polar atmosphere upon impact causing unusually extreme freezing conditions at lower latitudes like the year without a summer of 1812. The third tine of Satan’s pitchfork known as high sea surface temperatures indicating El Nino is located directly between the north and south hotspots and occurs during initial high particle densities related to impact of the debris stream.According to EPA, 21% of global green house gas emission is from industry sector and mining sector is one of the major emitters of green house gases. Scientists are certain that climate change effects are expected to increase in the coming decades and urge nations to implement mitigation measures. Implementation of Green technology at industrial level aid in reduction of global warming, green house effect, pollution and climate change. Present study aims to explore the importance of green mining of garnet and garnet based abrasive water jet cutting in reducing green house gas emission and climate change effects. M/s V.V.Mineral implemented two common sense steps manual mining and solar drying to address the challenge of climate change in mining and beneficiation of garnet. The case study finding shows manual mining operation adopted by M/s V.V.Mineral for garnet sand mining is green and completely reduced the emission of 0.893 - 1.19 kg CO2/ton sand, normally emitted through mechanised mining process practiced in the area. Implementation of solar drying in the beneficiation process results in elimination of 29.67 - 32.36 Kg CO2 emission by every ton of sand dried in fossil fuel based driers. Garnet is the commonly used abrasive around the world. Garnet based abrasive water jet cutting is an environment friendly green process. Since it is a cold process, all materials can cut without fuel combustion and heat generation process. This paper highlights the advantages of replacing thermal cutting process by garnet based abrasive water jet cutting in mineral fabrication sector to reduce air pollution in the form of fumes and gases and reduces CO2 emission and global warming.