Browsing by Author "A G, Jineesh"

This chapter provides an overview of methods of modifications of biodegradable polymers especially polylactic acid and polyhydroxyalkanoates for automotive applications. Methods for the modifications of biodegradable polymers such as plasticization and blending with other polymers to make those biodegradable polymers suitable for automotive applications are discussed in this chapter. The exterior and interior parts of automotive, which can be made from biodegradable parts, have been highlighted here. We have also discussed composites and nanocomposites of biodegradable polymers for automotive applications and their advantages over neat biodegradable polymers. The effect of different types of natural fibers and synthetic fillers on the toughness, ductility, and thermal stability of properties of biodegradable polymers is summarized. Prospects of biodegradable polymers and their composites for automotive applications are also discussed here. © 2023 Elsevier Inc. All rights reserved.

In recent years, thermally conductive polymer nanocomposites have garnered significant interest due to their wide application in the electronic industry. In the present work, we report thermally conductive silicone rubber-based nanocomposites at lower filler loading of polydopamine-coated copper nanowires (PDA@CuNW). First, copper nanowires (CuNW) are synthesized by the liquid phase reduction method and modified with polydopamine (PDA) by in-situ polymerization. The synthesized CuNW and PDA@CuNW are incorporated into Silicone rubber (SR) varying from 1 to 5 wt% via solution casting. The incorporation of 5 wt% PDA@CuNW resulted in a 62 % improvement in the thermal conductivity of SR. In addition, the nanocomposite showed the highest thermal effusivity of 735 Ws1/2m?2 K?1 even at 5 wt% loading. These results can be attributed to the better adhesion of PDA to the SR matrix confirmed by Field Emission-Scanning Electron Microscopy (FE-SEM). Thermogravimetric analysis showed that the modification of copper nanowires improved the thermal stability of SR. The electrical resistivity of SR increased with the addition of PDA@CuNW. The tensile stress-strain studies reveal that the strength of the SR/PDA@CuNW was improved compared to neat SR and SR/CuNW composites. Moreover, the elongation at break reached up to 972 % which is a 395 % improvement with respect to plain SR. In this work, simultaneous improvement in thermal conductivity and electrical resistivity is achieved while preserving the mechanical properties of the SR nanocomposites. Flexible nanocomposites with improved thermal and electrical properties and minimal filler loading have great significance in high-performance thermal management materials. © 2025 Elsevier Ltd

Biobased polyurethane nanocellulose nanocomposites were synthesized from cottonseed oil as the source for the biopolyol. The prepared composites were used to study the adsorption of Rhodamine B dye from water. Low functional polyol was derived from cottonseed oil using one-pot synthesis method. Nanocellulose was derived from pineapple leaves and then it was surface-functionalized via silylation. In-situ polymerization technique was used to incorporate the silylated nanocellulose into the polyurethane matrix. The prepared polyol from cottonseed oil was found to have an OH functionality of 2 which was confirmed by Fourier transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance (NMR) spectroscopy. Low functionality of polyol is the key factor in achieving flexible porous polyurethane. The silylated nanocellulose, polyurethane, and composites were characterized by FT-IR, X-ray diffraction analysis (XRD), and Scanning electron microscopy (SEM). The adsorption parameters were optimized using the Taguchi methodology and the adsorption efficiency was determined by carrying out adsorption at optimized parameters (5 wt% loading of silylated nanocellulose, pH 9, and temperature of 30 °C) for 8 h. Studies showed that the prepared composite has a high adsorption efficiency of 597 mg/g of silylated nanocellulose towards Rh-B.

Nanocellulose is a promising future material which has got attention due to its unique characteristics. Properties which make nanocellulose special are the eco-friendliness, high strength, stiffness, renewability, abundance, tunable surface characteristics, and low weight. This review addresses major factors like processing of nanocellulose, modification, properties, preparation of nanocomposites from nanocellulose, and their application in different fields. This review facilitates the selection of biomass sources, processing techniques for NC synthesis, application, and challenges. This review also emphasizes on different applications of nanocellulose reinforced polymer composites in different areas such as biomedical, packaging, electronic and environmental remediation, etc. Recent developments in the processing of cellulose nanocomposites using solution casting and other complex methods have been highlighted. As an emerging functional polymeric material, nanocellulose has become a research hotspot. The importance of nanocellulose in future includes the design of nanocellulose as per the specific user requirements, reduction of the production cost, and making customized products using nanocellulose using green processing. Hence this review is intended to provide new insights into the field of eco-friendly fundamental materials with in-depth perspectives and current research trends in its future applications. © 2024 Wiley-VCH GmbH.

Nanocellulose is a promising future material which has got attention due to its unique characteristics. Properties which make nanocellulose special are the eco-friendliness, high strength, stiffness, renewability, abundance, tunable surface characteristics, and low weight. This review addresses major factors like processing of nanocellulose, modification, properties, preparation of nanocomposites from nanocellulose, and their application in different fields. This review facilitates the selection of biomass sources, processing techniques for NC synthesis, application, and challenges. This review also emphasizes on different applications of nanocellulose reinforced polymer composites in different areas such as biomedical, packaging, electronic and environmental remediation, etc. Recent developments in the processing of cellulose nanocomposites using solution casting and other complex methods have been highlighted. As an emerging functional polymeric material, nanocellulose has become a research hotspot. the importance of nanocellulose in future includes the design of nanocellulose as per the specific user requirements, reduction of the production cost, and making customized products using nanocellulose using green processing. Hence this review is intended to provide new insights into the field of eco-friendly fundamental materials with in-depth perspectives and current research trends in its future applications.

Recently, considerable interest has been focused on developing greener and biodegradable materials due to growing environmental concerns. Owing to their low cost, biodegradability, and good mechanical properties, plant fibers have substituted synthetic fibers in the preparation of composites. However, the poor interfacial adhesion due to the hydrophilic nature and high-water absorption limits the use of plant fibers as a reinforcing agent in polymer matrices. The hydrophilic nature of the plant fibers can be overcome by chemical treatments. Cellulose the most abundant natural polymer obtained from sources such as plants, wood, and bacteria has gained wider attention these days. Different methods, such as mechanical, chemical, and chemical treatments in combination with mechanical treatments, have been adopted by researchers for the extraction of cellulose from plants, bacteria, algae, etc. Cellulose nanocrystals (CNC), cellulose nanofibrils (CNF), and microcrystalline cellulose (MCC) have been extracted and used for different applications such as food packaging, water purification, drug delivery, and in composites. In this review, updated information on the methods of isolation of nanocellulose, classification, characterization, and application of nanocellulose has been highlighted. The characteristics and the current status of cellulose-based fiber-reinforced polymer composites in the industry have also been discussed in detail.

New hybrid metal organic framework based polymer nanocomposite (ZIF-8/NC-PU) and interpenetrating polymer gel nanocomposites (NC-PU) were prepared for the adsorption of cationic (Rh-B) and anionic (IC) dyes from aqueous solution. The characterisation of the ZIF-8 based composites and gel composites is carried out using FT-IR and SEM analysis to investigate the chemical composition and morphology of the sample. Moringa oleifera seed pod based nanocellulose (5 wt%) is used as the filler in NC-PU gel composites and ZIF-8/NC-PU MOF composites. The optimal level of the most significant identified variables affecting the adsorption process were determined by the response surface methodology (RSM) using Plackett–Burman and Box–Behnken design. Adsorption capacity increased with the increase in dosage of the adsorbent, pH and initial dye concentration. Plackett–Burman was performed for the experiments involving the dyes Rh-B and Indigo carmine dyes. It gave 12 experiments in each trials and resulted in 3 significant parameters. Box–Behnken was further used to determine the optimum parameters for the adsorption keeping PU weight percentage as 3. The percentage uptake predicted by the model is in good agreement with the experimental values. The findings assume that the adsorbents could be used effectively as highly efficient adsorbents for the removal of multiple dyes from wastewater.

Nanosized m-BiVO4 and Sr-doped derivatives were prepared by solid state reactions, to produce Bi1-xSrxVO4 (X = 0%, 4%, 8% & 12%). XRD and Raman investigations confirmed the formation of BiVO4 phase. 8% and 12% doped samples contained a small fraction of secondary t-BiVO4 phase. SEM images exhibited flat and irregular nanoparticles (64–70 nm). Estimated band gaps were in visible region (2.34–2.42 eV). The materials were used to photodegrade malachite green and BVO-12 showed maximum efficiency ˜ 88% in 180 min. The catalyst was stable and effective for three cycles. Radical scavenging experiments proved the role of holes and hydroxyl radicals. Polymer nanocomposite films made of EOC and photocatalyst were prepared. 0.15 g catalyst loaded film showed maximum activity and recyclability.

Polyols from chaulmoogra seed oil and grape seed oil were prepared by epoxidation and ring opening of oxirane ring using lactic acid in nitrogen atmosphere with a control over their functionality. Nanocellulose was derived from Desmostachya Bipinnata grass leaves and further surface functionalized. Modified nanocellulose was used as filler to prepare porous flexible bio-based polyurethane nanocomposites via in-situ polymerization. Adsorption of malachite green (MG) dye from wastewater using the prepared polyurethane composites was carried out. The effect of varying factors such as weight percentage of filers (modified nanocellulose), dosage of the adsorbent, pH, temperature and time on the MG adsorption have been studied experimentally. Material characterization for prepared materials was carried out using FTIR, NMR, TGA, DSC, and SEM along with other physical and chemical methods. FTIR results indicated the presence of peaks at 1704 cm−1 for –C=O stretching vibrations from urethane groups, 1531 cm−1 for –NH bending, 1232 cm−1 for –C–N stretching and 1105 cm−1 for –C–O stretching in the urethane group (–NHCOO–) thus, indicating the formation of urethane linkage in the polyurethane. Polyols with functionality around 2.8 were obtained from the oils, which has contributed to forming flexible polyurethanes. Morphological studies indicate the nano fibrillation of cellulose and closed-cell porosity in polyurethane and its composites. The flexible porous PU and its nanocellulose composites displayed improved thermal stability from 256.3°C to 270.5°C. Taguchi’s L27 orthogonal array have been applied for experimental design and optimization and the results were analyzed using ANOVA for raw and S/N ratio. It was found that pH is the most influential factor for adsorption lead by quantity of nanocellulose, time, dosage of the adsorbent and temperature.

Plant fiber–reinforced biocomposites have emerged as sustainable alternatives to synthetic fiber reinforced composites due to their biodegradability, nontoxic nature, less environmental impact, and comparable technical performances. This chapter presents an overview of recent advances in the field of processing and treatment of plant fibers to be used as reinforcement in biocomposites. This chapter explores various extraction methods from various plant sources and the characteristics of the plant fibers obtained from these extraction methods. This chapter also discusses the role of both physical and chemical surface modification of plant fibers on the interfacial adhesion between fibers and polymer matrices and their impact on the properties of the composites. © 2026 Elsevier Ltd. All rights reserved.

Exceptional thermal conductivity of graphene and graphene-based nanomaterials is a key factor in driving their uses in various thermal management systems. This chapter explores the diverse thermal applications of graphene and its derivatives in advanced thermal management systems. The chapter examines the enhanced thermal performance of graphene-based nanofluids, graphene-based phase-change materials, and polymer-graphene nanocomposites. Critical role of these materials in improving the efficiency and reliability of electronic devices, energy storage systems, and renewable energy technologies is discussed in detail. Specific applications within these domains, including thermal interface materials, cooling solutions for electronics, and thermal management in batteries and solar cells, are also outlined. This chapter provides a comprehensive overview of the latest advancements in graphene-based thermal management solutions and their potential to address the growing demand for efficient thermal management systems in various sectors. © 2026 Elsevier Ltd. All rights reserved.