PARSOTAM H. PARSANIA^1,*, JIGNESH V. PATEL², JIGNESH P. PATEL³

Journal of Polymer Materials, Vol.40, No.3-4, pp. 271-284, 2023, DOI:10.32381/JPM.2023.40.3-4.9

Abstract Bisphenol-C epoxy crotonate resin was synthesized by reacting 8.09g epoxy resin of bisphenolC, and 2.15g crotonic acid using 25 mL 1,4-dioxane as a solvent, and 1 mL triethylamine as a catalyst at reflux temperature for 1-6 h. Solid epoxy crotonate (ECCR) is highly soluble in common organic solvents. ECCR was characterized by its acid (24.5-1.5 mg KOH/g) and hydroxyl (504.5-678.4 mg KOH/g) values. The structure of ECCR is supported by FTIR and 1 HNMR spectroscopic methods. A DSC endothermic transition at 229o C indicated melting followed by thermal polymerization of ECCR. ECCR is thermally stable up to 320o C and… More >

NEETU TRIPATHI, DIBYENDU S. BAG^*, MAYANK DWIVEDI

Journal of Polymer Materials, Vol.40, No.3-4, pp. 227-269, 2023, DOI:10.32381/JPM.2023.40.3-4.8

Abstract Over the last three decades, there has been considerable interest in the captivating mechanical properties displayed by auxetic materials, highlighting the advantages stemming from their distinct negative Poisson's ratio. The negative Poisson's ratio observed in auxetic polymeric materials is a result of the distinctive geometries of their unit cells. These unit cells, encompassing structures such as chiral, re-entrant, and rotating rigid configurations, are carefully engineered to collectively generate the desired auxetic behaviour. This comprehensive review article explores the field of auxetic polymeric materials, offering a detailed exploration of their geometries, fabrication methods, mechanical properties, and characterisation. The diverse applications of… More >

K. KRISHNAMOORTHY^a,*, N. PRABHU^b

Journal of Polymer Materials, Vol.40, No.3-4, pp. 215-226, 2023, DOI:10.32381/JPM.2023.40.3-4.7

Abstract The acoustic emission monitoring with artificial neural networks predicts the ultimate strength of glass/epoxy composite laminates using Acoustic Emission Data. The ultimate loads of all the specimens were used to characterise the emission of hits during failure modes. The six layered glass fiber laminates were prepared (in woven mat form) with epoxy as the binding medium by hand lay-up technique. At room temperature, with a pressure of 30 kg/cm², the laminates were cured. The laminates of standard dimensions as per ASTM D3039 for the tensile test were cut from the lamina. The Acoustic Emission (AE) test was conducted on these… 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 >

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 >

CONGHUI XU, ZHEQING GONG, XIAOLONG CHEN, LIJUN CHEN^*

Journal of Polymer Materials, Vol.40, No.1-2, pp. 47-58, 2023, DOI:10.32381/JPM.2023.40.1-2.4

Abstract The self-crosslinking polyacrylate latex was prepared via the semi-continuous seed emulsion polymerization technology that methyl methacrylate(MMA) and butyl acrylate (BA)were used as the main monomers and hexafluorobutyl methacrylate (HFMA) and monobutylitaconate (MBI) were used as the modified monomers and glycidyl methacrylate (GMA) was used as the crosslinked monomer which were emulsified with the environmentally friendly mixed surfactant of the isomeric triethylene (9) ether (E-1309) and the lauryl polyoxyethylene ether sulfosuccinate disodium salt (MES-30). The resultant latex and its film is characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), laser particle sizer, contact angle determinator. The comparison of… More >

Xiao Sun¹, Jiangbo Tong¹, Yuliang Zhang^2,*, Haibing Cai³, Wen Zhou⁴, Xiaoqi Jia⁵, Litao Ou⁶

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 725-737, 2024, DOI:10.32604/fdmp.2023.045541

Abstract Centrifugal pumps are widely used in the metallurgy, coal, and building sectors. In order to study the hydraulic characteristics of a closed impeller centrifugal pump during its shutdown in the so-called power frequency and frequency conversion modes, experiments were carried to determine the characteristic evolution of parameters such as speed, inlet and outlet pressure, head, flow rate and shaft power. A quasi-steady-state method was also used to further investigate these transient behaviors. The results show that, compared to the power frequency input, the performance parameter curves for the frequency conversion input are less volatile and smoother. The characteristic time is… More >

Yuanjun Dai^1,2, Jingan Cui¹, Baohua Li^1,*, Cong Wang¹, Kunju Shi¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 771-786, 2024, DOI:10.32604/fdmp.2023.029584

Abstract A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient, lift coefficient, and drag coefficient. The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil; however, at small attack angles, its influence is significantly reduced. When the angle of attack exceeds the critical stall angle and the flap height is 1.5% of the chord length, the influence of the flap becomes very evident. As the flap height… More >

Yuejie Li^1,2,*, Shijun Li³

CMC-Computers, Materials & Continua, Vol.78, No.3, pp. 3041-3070, 2024, DOI:10.32604/cmc.2023.045741

Abstract 6G is envisioned as the next generation of wireless communication technology, promising unprecedented data speeds, ultra-low Latency, and ubiquitous Connectivity. In tandem with these advancements, blockchain technology is leveraged to enhance computer vision applications’ security, trustworthiness, and transparency. With the widespread use of mobile devices equipped with cameras, the ability to capture and recognize Chinese characters in natural scenes has become increasingly important. Blockchain can facilitate privacy-preserving mechanisms in applications where privacy is paramount, such as facial recognition or personal healthcare monitoring. Users can control their visual data and grant or revoke access as needed. Recognizing Chinese characters from images… More >