Polymer Composites For Applications Research Articles

Spherical CaCO3: Synthesis, Characterization, Surface Modification and Efficacy as a Reinforcing Filler in Natural Rubber Composites

Natural rubber (NR), an important natural polymer derived from the Hevea brasiliensis tree, has been widely used in the rubber industry owing to its excellent elastic properties. However, it requires reinforcing fillers to improve its mechanical properties for the manufacturing of rubber products. Generally, calcium carbonate (CaCO3) is employed as a non-reinforcing filler. This work aimed to synthesize spherical-shaped CaCO3 at a submicrometric scale without and with surface treatment and explore its utilization as a reinforcing filler in NR composites. The morphological shape and polymorphic phase of CaCO3 were investigated using SEM, TEM, XRD, ATR-FTIR and Raman techniques. The mechanical properties of various amounts (0 to 60 phr) of CaCO3-filled NR composites were explored. As a result, the NR/treated CaCO3 composites provided higher tensile strength than the NR/untreated CaCO3 composites and pure NR at all filler loadings. This may have been due to the improved interfacial interaction between NR and CaCO3 with the improved hydrophobicity of CaCO3 after treatment with olive soap. The optimal filler loading was 20 phr for the highest tensile strength of the rubber composites. In addition, the elongation at break of the NR/treated CaCO3 was slightly decreased. Evidence from SEM and FTIR revealed the vaterite polymorph and shape stability of CaCO3 particles in the NR matrix. The results demonstrate that the particle size and surface treatment of the filler have essential effects on the mechanical property enhancement of the rubber composites. Synthesized spherical CaCO3 could be a potential reinforcing filler with broader application in polymer composites.

Extraction and Characterization of Novel Ligno-Cellulosic Fiber from Wrightia tinctoria and Cebia pentandra Plant for Textile and Polymer Composite Applications

Natural fibers derived from cellulose and ligno-celluloses materials have many advantages, such as being renewable, low density, inexhaustible, and cheap rather than synthetic fibers. Researchers and scientists are searching for a new fiber source that can be processed environmentally sustainable. The aim is to produce an organic and Eco-friendly product. The present investigation aims to extract and characterize ligno-cellulosic fiber from the seedpod of Wrightia tinctoria (WT) and Cebia pentandra (CP) plants. The extraction of WT fibers (WTFs) and CP fibers (CPFs) was carried out using the hand-stripping method. The structural and functional Characterization of WTFs and CPFs were determined using Scanning Electron Microscope (SEM), Fourier Transform Infrared (FT-IR) spectroscopy, Chemical analysis, X-ray diffraction studies (XRD), and the thermal behavior of fibers determined by using Thermo Gravimetric Analysis (TGA). The results indicated that WTFs composed of 75% cellulose, 14% lignin, and 0.55% wax content were, as the CPFs were composed of 38% cellulose, 15% lignin, and wax content of 2.34%. The SEM micrograph confirms that both fibers were hollow structures with thin cell walls and luminous because of the wax content presence on the surface of the fiber. The crystallinity percentage of WTFs and CPFs was calculated from XRD studies and is valued at 62% and 52%. Thermo gravimetric analysis revealed that WTFs and CPFs were thermally stable up to 460°C and 350°C. The above characterization results confirm that WTFs and CPFs have a wide scope in textile and polymer composite applications.

Chemical, thermal and morphological properties of polybutylene succinate-waste pineapple leaf fibres composites

The use of natural fibres for polymer composite applications has been widely researched due to the biodegradable and lightweight nature of natural fibres. To achieve good adhesion and compatibility between the matrix and the fibre filler, prior modification of the fibre surface via the use of various methods has been found to be effective. The natural fibres have been modified using chemical, physical, radiation, grafting and biological methods. The current study aims to evaluate the effect of sodium hydroxide-treated waste pineapple leaf fibres (PALF) content on the chemical, thermal, and morphological properties of polybutylene succinate (PBS) composites. PBS-PALF composites with fibre content ranging from 0 to 20 wt% were prepared using an internal mixer and their properties were studied using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA) and Scanning electron microscope (SEM). The FTIR results showed no noticeable functionality differences among the composites, however, carbonyl groups from PBS polymer at ∼1700 cm−1 and hydroxyl groups from PALF at ∼3000 cm−1 were observed in the composites. The water absorption uptake of the composites increased with fibre content due to the hydrophilic nature of the PALF fibres and the highest water absorption percentage achieved was ∼30 %. The incorporation of the fibres into the PBS matrix decreased the crystallinity of the composites as shown by the XRD peaks at 2ϴ = 22 and 30°. SEM images of the composites with 20 wt% exhibited morphologies where the fibres protruded out from the polymer matrix, and this was ascribed to the agglomerated fibres which were poorly mixed with the matrix at the higher fibre content. Overall, the incorporation of high PALF content in the composites disrupted the crystallinity and thermal stability of the PBS matrix. The composites have potential in industrial agricultural mulching film applications due to their sustainability characteristics.

Superior high-temperature mechanical and thermal performance of carbon fiber/epoxy composites by incorporating highly dispersed aramid nanofibers

Enhancing the high-temperature properties of polymer-matrix fiber-reinforced composites is a challenging task, given the thermal limitations of polymer resins. In this study, we propose a straightforward and efficient method for producing high-performance carbon fiber/epoxy composites with superior high-temperature properties by incorporating highly dispersed aramid nanofibers. To achieve high dispersion of aramid nanofibers in the epoxy, we used a sequential solvent exchange method, which allowed us to fabricate B-stage cured resin films. The aramid nanofiber-hybridized carbon fiber composite, manufactured using resin film infiltration, demonstrated impressive mechanical and thermal properties. Specifically, in the glass transition temperature range at high temperatures, the composite provided 3.1, 5.1, and 6.8 times higher Young's modulus, tensile strength, and short beam strength, respectively, compared to the unmodified composite. Moreover, incorporating aramid nanofibers significantly increased the glass transition temperature by 31 °C, resulting in 2.4 times higher storage modulus and improved thermal stability with an increase in the total weight residue at 800 °C by 33.7 %. Therefore, the highly dispersed aramid nanofiber-embedded carbon fiber composite shows great potential for use in high-performance polymer composite applications.

Metal oxide nanofillers induced changes in material properties and related applications of polymer composites

Nanometal oxides have attracted considerable research interest because of the widespread applications in which nanomaterials can be synthesised in various oxide forms that can adopt various structural geometries with unique electronic band structures. Additionally, nanometal oxides provide unique features imputed to quantum confinement effects that stimulate changes in their optical, electrical, and optoelectronic behaviours. Meanwhile, introducing such nanometal oxides into host polymeric materials enables the formation of advanced polymeric nanocomposites with versatile properties. Even so, the utilisation of such nanocomposites in diverse potential applications requires a fundamental understanding of their inherent material functionalities. Therefore, this document aims to demonstrate the importance of polymer nanocomposites with a special focus on the impact of nanometal oxides to enhance the optical and electrical behaviours of polymer composites for advanced optoelectronic and energy storage applications.

Application of Artificial Neural Networks in Polymer Composites: A Review

Artificial neural networks (ANN), which have been a hot topic in the field of artificial intelligence (AI) since the 1980s, are widely applied these years for their strong ability in the field of nonlinear mapping, pattern recognition, robots, automatic control, biology, economy and so on. This review presents and summarizes the history of artificial neural networks, briefly introducing the application of artificial neural networks. After that, the paper focuses on an overview of research advances in neural networks for polymer composites and introduces several classical categories of applications. Finally, we look ahead to the development of neural network applications in polymer composites and provide a future outlook for the application of artificial neural network in polymer composites.

Synthesis and application of magnetic polystyrene polymer composites for magnetic solid-phase extraction of three fluoroquinolones from milk samples

Synthesis and application of magnetic polystyrene polymer composites for magnetic solid-phase extraction of three fluoroquinolones from milk samples

Effect of alkali treatment on novel natural fiber extracted from palmyra palm primary flower leaf stalk for polymer composite applications

Effect of alkali treatment on novel natural fiber extracted from palmyra palm primary flower leaf stalk for polymer composite applications

Isolation and characterization of a novel lignocellulosic fiber from Butea monosperma as a sustainable material for lightweight polymer composite applications

Isolation and characterization of a novel lignocellulosic fiber from Butea monosperma as a sustainable material for lightweight polymer composite applications

Modern Applications of Polymer Composites in Structural Industries: A Review of Philosophies, Product Development, and Graphical Applications

Polymer-based materials have been discovered as the most outstanding class of material that is fast displacing other materials in all areas of human needs. The dire need for durable, aesthetic, and lightweight materials has favored the increasing demand for polymer-based materials in structural industries. The application of polymeric-based materials in all aspects of human endeavor is based on their ease of formation, lightweight, and acceptable properties. The philosophy of composite development has also contributed immensely to the production of components from polymer-based materials suitable for several structural applications. More recently, interest in green materials also encourages the use of polymer-based materials in structural applications. The suitability of a material for any selected application is justified by structural and environmental compatibility. Thus, researchers have focused on these two major areas in their investigations for product development. Despite continuous efforts in these two directions, they are still issues of great concern to researchers in satisfying the desires of users presently. Hence, this review presents the philosophies of researchers, the product developed, and areas of application for polymer-based materials in structural industries such as biomedical, building and construction, energy, and sports. The paper advanced graphical presentation of the application of developed products and strongly supports the recommendation of polymer-based composite materials as a viable alternative to other materials due to their remarkable capabilities in many application domains.

Isolation and characterization of agro-waste biomass sapodilla seeds as reinforcement in potential polymer composite applications

Fillers or particulate fillers find a growing utilization as reinforcement material in polymer composites due to their ability to enhance the properties of the ensuing composites. The discarded seed in sapodilla fruit is available in abundant and the shell of the seed can be used as a reinforcing filler. The primary goal of this study is to extract and characterize the sapodilla seed shell powder (SSS) physically and chemically in order to assess its potential for reinforcement as a particulate filler in polymer composites. The sapodilla seed shell filler was characterized experimentally by Physio-chemical analysis, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Energy dispersive X-ray analysis (EDAX). The morphology and the filler size were determined by Scanning electron microscopy (SEM) and Particle size analysis. The thermal degradation behaviour was evaluated by Thermogravimetric analysis (TGA).

Extensive characterization of pretreated/enzyme treated cellulosicAreca catechu L. peduncle fiber for polymer composite applications

AbstractThis paper investigates thermo‐mechanical, chemical, and morphological characteristics of alkali pretreated and enzyme treatedAreca catechutree peduncle fibers (ACTPFs) for probable reinforcement in polymer composites. ACTPFs were pre‐treated with 0.4 M NaOH solution and treated with enzymes such as xylanase, laccase, and pectinase before investigations. Alkali pre‐treated ACTPF (AACTPF) cum pectinase treated AACTPF (PAACTPF) exhibited maximum cellulose content 57.28 wt% and single fiber tensile strength 203.5 ± 22.12 MPa. Further, the crystallinity index and crystal size of PAACTPF was determined as 55% and 12.9 nm by x‐ray diffraction analysis. Also, the prevalence of chemical bonds and thermal stability up to 233°C in PAACTPF was exposed through Fourier transform infrared spectroscopy analysis and thermogravimetric analysis respectively. Moreover, the coarse surface of PAACTPF viewed through scanning electron microscope owing to removal of amorphous contents makes it a considerable counterpart for substitutional reinforcement to artificial fibers in polymer composites.

Periquiteira (Cochlospermum orinocense): A Promising Amazon Fiber for Application in Composite Materials.

Natural lignocellulosic fibers (NLFs) have in recent decades appeared as sustainable reinforcement alternatives to replace synthetic fibers in polymer composite material applications. In this work, for the first time, the periquiteira (Cochlospermum orinocense), a lesser known NLF from the Amazon region, was analyzed for its density and, by X-ray diffraction (XRD), to calculate the crystallinity index as well as the microfibrillar angle (MFA), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron analysis (SEM) and tensile strength. The apparent density found for the periquiteira fiber was 0.43 g/cm3, one of the NLF's lowest. XRD analysis indicated a crystallinity index of 70.49% and MFA of 7.32°. The TGA disclosed thermal stability up to 250 °C. The FTIR analysis indicated the presence of functional groups characteristic of NLFs. The SEM morphological analysis revealed that the periquiteira fiber presents fine bundles of fibrils and a rough surface throughout its entire length. The average strength value of the periquiteira fiber was found as 178 MPa. These preliminary results indicate that the periquiteira fiber has the potential to be used as a reinforcing agent in polymeric matrices and can generate a lightweight composite with excellent mechanical properties that can be used in various industrial sectors.

Effect of alkali treatment on novel natural fiber extracted from the stem of Lankaran acacia for polymer composite applications

Effect of alkali treatment on novel natural fiber extracted from the stem of Lankaran acacia for polymer composite applications

Research advances in preparation, mechanism and application of thermally conductive and electrically insulating polymer composites in thermal management materials: A review

Today, electronic components are gradually developing towards miniaturization and multi-function. During the use of electronic components, a large amount of heat will be generated, which seriously limits the performance and service life of electronic components. Therefore, the preparation of thermal management material (TMMs) with high thermal conductivity (λ) can effectively solve the problem of thermal accumulation in electronic components. Compared with the preparation of intrinsic thermal conductive polymer composite, the method of filling thermal conductive filler in polymer matrix can better improve the λ of polymer composite. This review discusses the heat conduction mechanism of polymer and the factors affecting λ of polymer composites, including the type of filler, the shape and distribution of filler, and the functional surface treatment of filler. Then, the different methods of preparing thermally conductive and electrically insulating polymer composites (TCEIPCs) are introduced in detail. The application of polymer composites in thermal management is also introduced.

Thermoset polymer composites with gradient natural and synthetic fiber reinforcement: Self-healing, shape-memory, and fiber recyclability

Natural fibers have high potential as renewable reinforcement for polymers; however, their lower load-carrying capacity compared to synthetic fibers significantly limits the wide application in fiber-reinforced polymer composites. In laminated composite beams under bending load, the normal stress is the highest on the top and bottom layers but is zero at the mid-plane, with almost a linear normal strain distribution. Although the shear stress is the highest at the mid-plane, it may not be a major concern as most polymers can survive the high shear stress. Using this concept, we have designed a hybrid fiber reinforcement in a gradient manner: from the surface to the mid-plane were carbon fiber, glass fiber, and natural jute fiber, respectively. A newly synthesized self-healable shape memory polymer was used for laminating the fibers. Performance characterizations demonstrated that even using a significant amount of natural fibers in the composites, the samples with gradient fiber reinforcement showed competitive mechanical properties to fully carbon or glass fiber reinforced composites and much higher mechanical properties than the composite prepared with entirely natural fibers or glass fibers. For example, the gradient composites show up to 550 % flexural strength of the composites made of fully natural fibers, and around 14 % and 34 % higher flexural strength than that of the composites made of pure glass and pure carbon fibers, respectively. In addition, the composites retain excellent self-healing, shape-recovery, and fiber-recycling properties.

Nanocellulose and its polymer composites: preparation, characterization, and applications

Natural and synthetic polymeric materials are in high demand that continues to increase year after year, making them essential part of human life. By employing cellulose and cellulose derivatives as fillers for either synthetic or natural polymers, the environmental impact of non-biodegradable materials can be reduced. Nanocellulose (NC) materials have recently gained a lot of interest as potential fillers for reinforcing polymeric materials. The article highlights the different sources of NC, including plant sources, marine algae, bacteria and sea animals. The use of dewaxing solvents, alkali, bleaching agents, enzymes, 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO), ammonium persulfate (APS), ionic liquids, deep eutectic solvents and steam explosion for pretreatment of lignocellulosic materials was explained. In addition, this review considers the extraction methods, including mechanical fibrillation for the production of cellulose nanofibers (CNF) and acid hydrolysis for the production of cellulose nanocrystals (CNC). Furthermore, the article discusses recent advances in the fabrication of NC polymer composites, such as the melt mixing process, solution casting, 3D printing, electrospinning and pickering emulsions methods. The different characterization techniques of NC polymer composites were discussed in this article. Many promising applications of NC polymer composites, such as sensors, electronics, fuel cells, construction, paper and board, biomedical, food packaging, water purification, aerogels, and hydrogels are considered. <br> The bibliography includes 299 references.

Fabrication of highly hydrophobic layered double hydroxide decorated with tannic acid cross-linked phosphazene as a novel flame retardant for polypropylene

Layered double hydroxide (LDH) is a promising flame-retardant nano-additive for polymers, however, its efficiency is highly based on its composition and dispersity. Based on this cognition, a core-shell LDH-based architecture (LDH@TA-HP) was designed using LDH sheet as core and tannic acid and phosphazene cross-linkd polymers network (TA-HP) as shell. In the flame retardant process, renewable tannic acid (TA) as a carbon source with phosphazene was combined to form an intumescent flame-retardant system, which synergizes with the “tortuous path” effect of LDH which greatly enhance the flame retardancy of PP and LDH@TA-HP composites (PP/LDH@TA-HP). With the addition of 20 wt% LDH@TA-HP, the peak heat release rate and total smoke production of the PP/LDH@TA-HP composites were decreased by 63.5% and 47.6%, respectively, in comparison with those of Neat PP. The flame retardant level reached UL-94 V-0 rating and the limiting oxygen index (LOI) value of PP/LDH@TA-HP composites reached 30.1%, which was related to the “tortuous path’’ effect of LDH and the formation of the intumescent char layer of TA-HP. This investigation provided a facile strategy for the design of multifunctional LDH-based hybrids, expanding LDH potential applications in polymer composites.

Natural Polymeric Composites Derived from Animals, Plants, and Microbes for Vaccine Delivery and Adjuvant Applications: A Review.

A key element in ensuring successful immunization is the efficient delivery of vaccines. However, poor immunogenicity and adverse inflammatory immunogenic reactions make the establishment of an efficient vaccine delivery method a challenging task. The delivery of vaccines has been performed via a variety of delivery methods, including natural-polymer-based carriers that are relatively biocompatible and have low toxicity. The incorporation of adjuvants or antigens into biomaterial-based immunizations has demonstrated better immune response than formulations that just contain the antigen. This system may enable antigen-mediated immunogenicity and shelter and transport the cargo vaccine or antigen to the appropriate target organ. In this regard, this work reviews the recent applications of natural polymer composites from different sources, such as animals, plants, and microbes, in vaccine delivery systems.

Effects of bondline defects on the bond behaviour of CFRP-steel double strap joints

Adhesive bonding is used frequently for the applications of carbon fiber-reinforced polymer (CFRP) composites in steel structures such as strengthening or joining. However, the bondline defects are inevitable and could negatively affect the bond behaviour between CFRP and steel. Thus, the bondline defects represent a critical hazard and require careful assessment. This paper presents an experimental and numerical study on the effects of bondline defects on the bond behaviour of CFRP-steel double strap joints. The variables include the defect size (up to 35% of the bonded area), number (up to 45) and locations in the bondline. Multiple defects with mixed sizes are considered in a numerical analysis to investigate the effect of the defect number in more detail. It is found that the bondline defects lead to a reduction in the joint capacity. The highest reduction in capacity (36%) is observed when multiple small-sized defects are presented in the bondline. With the increment of the defect area, the failure mode becomes a combination of steel-adhesive interface debonding and CFRP delamination. A design framework is proposed based on the experimental and numerical results for the conservative prediction of the joint capacity with consideration of bondline defects.