SOBHA KOTA^*, RATNAKUMARI ANANTHA, VAYUNANDANA RAO GOVADA, PRADEEP DUMPALA

Journal of Polymer Materials, Vol.40, No.3-4, pp. 285-303, 2023, DOI:10.32381/JPM.2023.40.3-4.10

Abstract The exoskeleton of marine shrimp contains a natural, biocompatible polymer chitin, which is dumped as a waste. The study proposes the sustainable single-pot-extraction of chitosan from the waste and its use in the fabrication of wound-dressings, and thus leverage its piezoelectric, antioxidant, hypoglycaemic and medicinal properties in wound-healing. The Fourier transform infrared spectrum revealed that marine chitosan contains functional groups with N-O, O-H, and CO stretching. Scanning electron micrographs demonstrated the spherical and mesoporous structures of the extracted chitosan. X-ray diffraction analysis showed a semi-crystalline phase of chitosan particles with a mean size of 28.9 nm. The film prepared with… More >

ARUN KUMAR M, JAYAKUMARI LS^*, RAMJI CHANDRAN

Journal of Polymer Materials, Vol.40, No.3-4, pp. 141-156, 2023, DOI:10.32381/JPM.2023.40.3-4.2

Abstract Nanocomposites are very important materials because it imparts superior properties than other composites with low level of filler loading. Styrene butadiene rubber (SBR) is a non-polar rubber which acts as an insulator and has low electrical conductivity. Graphene platelet nano-powder from 0.1 to 1.25 phr level is incorporated into SBR rubber in order to improve the electrical properties. Comparative studies on electrical and mechanical properties of styrene butadiene rubber with graphene platelet nano-powder (GPN) by varying the filler content are made. The incorporation of Graphene platelet nano-powder increases the electrical conductivity in styrene butadiene rubber. It has been observed that… More >

NURUL HAYATI YUSOF^1,*, DAZYLAH DARJI¹, TAN KIM SONG¹, NGHIEM THI THUONG²

Journal of Polymer Materials, Vol.39, No.1-2, pp. 151-166, 2022, DOI:10.32381/JPM.2022.39.1-2.10

Abstract In this work, a pure gum mould made of prevulcanized natural rubber/cloisite-Na⁺ nanocomposite (PVNR/CN) was prepared and characterized for ornament application. The suitable conditions to prepare PVNR/CN latex mixtures and the properties of the resulting PVNR/CN nanocomposites were investigated. The optimum CN concentration in the latex mixture was 1.0 phr, with the properties of 60 wt% total solid content, more than 600 sec mechanical stability time, lower than 350 cP Brookfield viscosity, and pH 10. The properties of PVNR/CN nanocomposite showed high strength, moderate hardness, and good thermal stability. The morphology by TEM showed well dispersion of CN particles in… More >

PRABHAT KUMAR, ANJANA SARKAR, PURNIMA JAIN^*

Journal of Polymer Materials, Vol.39, No.1-2, pp. 121-135, 2022, DOI:10.32381/JPM.2022.39.1-2.8

Abstract Biocompatible graphene derivative materials (GBMs) to harness the maximum potential of pristine graphene biologically, is the most important strategy for its advanced applications in pharmaceutical and other biomedical fields. Currently, scientists are trying to find this by using biopolymer nanocomposites or anchored materials. Nevertheless, tuning the bare GBMs towards biocompatibility is a beautiful approach to exploit the fundamental potential of pristine graphene vis-à-vis suppressing the effects of incorporated biopolymers or anchored materials. Herein, a large-scale, cost-effective, facile, and environment-friendly green synthetic strategy is used for the synthesis of reduced graphene oxide (rGO) nanosheet using L-ascorbic acid (L-AA) as a reducing/stabilizing/capping… More >

HADIMANI SHIVAKUMAR¹, GURUMURTHY G. D.¹, BOMMEGOWDA K. B.², S. PARAMESHWARA³

Journal of Polymer Materials, Vol.40, No.1-2, pp. 93-103, 2023, DOI:10.32381/JPM.2023.40.1-2.8

Abstract Polymer composites are increasing in demand in energy storage applications including in the electronic as well as electrical industries due to the ease of processing of these materials with associated advantages like light weight, corrosion resistance, and high mechanical strength. In this investigation, efforts are made to enhance the charging and discharging properties of epoxy/carbon fabric composite by the addition of graphene nanoplatelets (GNPs) into the epoxy/ carbon matrix. The performance of the composites with graphene platelets of 0.5 to 5 wt. % in epoxy were characterized and 1wt.% percolation threshold was observed poor performance in gravimetric charge and discharge… More >

S. ARULMURUGAN^a,*, N. VENKATESHWARAN^a, S. KUMAR^a, P. CHANDRASEKAR^a

Journal of Polymer Materials, Vol.40, No.1-2, pp. 83-91, 2023, DOI:10.32381/JPM.2023.40.1-2.7

Abstract In this research, the effect of UV light on the mechanical properties of jute polymer nanocomposites was evaluated. Due to the fact that photodegradation is a surface process and is confined to the degradation of the mechanical characteristics of polyester resin, this study focuses on the resin quality. Therefore, test samples comprised of fibre-reinforced polyester nanoclay composites were fabricated different weight ratios of nanoclay. They were put through UV exposure in an Ultraviolet (UV) chamber. Tensile testing samples were made in accordance with ASTMD638 and had a minimum thickness of 3 mm. Additionally, specimens for Flexural and Impact testing were… More >

B. BRAILSON MANSINGH¹, K. L. NARASIMHAMU², K. C. VARAPRASAD³, J. S. BINOJ^4,*, A. RADHAKRISHNAN⁵, ALAMRY ALI⁶

Journal of Polymer Materials, Vol.40, No.1-2, pp. 71-82, 2023, DOI:10.32381/JPM.2023.40.1-2.6

Abstract Several agro-wastes are rich in natural fibers and finds scope to be used as reinforcement in composite industry. These natural fibers have some advantages over man-made fibers, including low cost, light weight, renewable nature, high specific strength and modulus, and availability in various forms worldwide. In this paper, the effect of surface modification of leaf sheath coconut fiber (LSF) (an agro-waste) reinforced in phenol formaldehyde matrix composites with silicon carbide (SiC) nano particles as filler material were investigated for its mechanical characteristics. The investigation portrays that coconut LSF (CLSF) modified with potassium permanganate reinforced polymer composite with SiC nano particles… More >

SHIVA ARUN^a, VINAY KUMAR SINGH^a,#, PRABHA BHARTIYA^b, PRADIP KUMAR DUTTA^c,*

Journal of Polymer Materials, Vol.40, No.1-2, pp. 19-31, 2023, DOI:10.32381/JPM.2023.40.1-2.2

Abstract Biocompatible polymer chitosan has note-worthy applications in biomedical science. Nanohybrids synthesized by using chitosan as an encapsulating unit for polyoxometalates (POMs) and study of its biomedical applications is a fast-emerging field. In this research work, a lacunary polyoxometalate (α-K₈SiW₁₁O₃₉) has been synthesized and then alkylsilane has been inserted into its lacunary position. It has been then reacted with 2-hydroxy-1-naphtaldehyde followed by copper metalation and finally encapsulated into chitosan by using the ionotropic gelation technique, in which the chitosan and the POM served as cation and anion, respectively. The bands in UV-Vis spectra at characteristic wavelength indicate that the organosilane is… More >

Ritesh Singh¹, Abhishek Gupta¹, Akshoy Ranjan Paul¹, Bireswar Paul¹, Suvash C. Saha^2,*

Energy Engineering, Vol.121, No.4, pp. 835-848, 2024, DOI:10.32604/ee.2024.046849

Abstract A parabolic trough solar collector (PTSC) converts solar radiation into thermal energy. However, low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power plants. Thermal performance of PTSC is enhanced in this study by incorporating magnetic nanoparticles into the working fluid. The circular receiver pipe, with dimensions of 66 mm diameter, 2 mm thickness, and 24 m length, is exposed to uniform temperature and velocity conditions. The working fluid, Therminol-66, is supplemented with Fe₃O₄ magnetic nanoparticles at concentrations ranging from 1% to 4%. The findings demonstrate that the inclusion of nanoparticles increases the convective heat… More >

R. Madan Kumar¹, R. Srinivasa Raju², F. Mebarek-Oudina^3,*, M. Anil Kumar⁴, V. K. Narla²

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 15-34, 2024, DOI:10.32604/fhmt.2024.048045

Abstract The primary aim of this research endeavor is to examine the characteristics of magnetohydrodynamic Williamson nanofluid flow past a nonlinear stretching surface that is immersed in a permeable medium. In the current analysis, the impacts of Soret and Dufour (cross-diffusion effects) have been attentively taken into consideration. Using appropriate similarity variable transformations, the governing nonlinear partial differential equations were altered into nonlinear ordinary differential equations and then solved numerically using the Runge Kutta Fehlberg-45 method along with the shooting technique. Numerical simulations were then perceived to show the consequence of various physical parameters on the plots of velocity, temperature, and… More > Graphic Abstract