Formulation Of Composite Materials Research Articles

Development of composite materials from recycled irrigation tape and corn stover

In this work, the formulation of composite materials of Recycled Irrigation Tape and Corn Stover (r-IT/CS) with additives, were studied. The variables analyzed were the size effect and the percentage of fibers. The r-IT/CS composites were processing in a twin screw extruder and compression molded. The materials characterization were by tension, bending, impact, hardness, and DSC measurements. As the fiber concentration and length increased, modulus, resistance (tension and bending), and hardness increased, but impact resistance decreased in comparison with the r-IT matrix. The percentage of crystallinity decreased by 4% with the addition of the CS fibers. The properties of the composite materials were similar to those of the polymeric matrix. These results open the possibility of using them as packaging.

Performance comparison between glass and basalt fibre-reinforced composites for an automotive seat backrest

In recent years, the automotive industry has been developing lightweight components in order to comply with stricter fuel consumption regulations. In fact, car mass reduction plays an important role in reducing fuel consumption and CO2 emissions. Composite materials are very promising solutions because of their potential to reduce mass by replacing traditional steel components, while ensuring safety requirements and structure reliability. However, they might present some issues in terms of sustainability and cost. This paper presents a methodology developed to carry out safety tests on a virtual automotive seat and then assess the structural practicability of using a more sustainable material, the Basalt Reinforced-Fibre Polymer (BFRP), as a replacement of the original material, the Glass Reinforced-Fibre Polymer (GFRP). The starting point of this study was the mechanical characterisation of both traditional and green composites. Then, the composite material formulation MAT-58 was optimised to correlate the simulated and experimental results. Finally, static and energy absorption simulation tests were performed according to the ECE R17 regulation. The seat model was compliant with the safety requirements in all cases studied, and both composites presented a similar structural performance.

Utilization of Polymer Composite for Development of Sustainable Construction Material

Polymers have gained an extensive application due to their versatility of properties and benefits. Hence, the polymer blends and composites reinforced with different infusions at different scales, macro to nanofillers, can be fabricated, leading to specific tailormade applications. The main objective of this investigation is to overview the various studies carried out to reuse the waste materials like electroplating sludge, fly ash, etc. For the development of construction materials. This paper summarizes the use of polymers in composite material formulations for the development of building materials such as lightweight concrete, protective coatings, paver blocks, bricks, and structural components. Different tests, namely viscosity, density, flash point, amine value, and epoxy equivalent weight, were performed on polymers to find their suitability as binder materials. Various laboratory tests such as compressive strength, water absorption, tear resistance, flexural strength, and split tensile tests were carried out to determine the mechanical properties of the developed materials. By using polymers with the addition of sustainable filler and waste materials, the replacement of costly raw material can be achieved by more than 50% in the case of paver blocks, up to 60% in bitumen-polymer composite, 80% in case of lightweight concrete and polymer-based panels. This insight gives the framework for the selection of different materials, optimization of combining ratio of materials, and their testing for the development of polymer-based materials.

Wave energy harvesting using Silicone as Electro-active Polymers

Wave energy is one of the renewable resources, which is very little exploited at the moment. Note that the energy transmitted through this energy is important, 140 to 700 TWh/year according to the WEC (World Energy Council), that is 1 to 5% of the world's electricity demand. The mechanical energy of the waves can be converted into electricity thanks to a completely flexible system based on the technology of electro-active polymers (EAP). These materials have the ability to generate a voltage when subjected to a certain stress and conversely to deform when subjected to an electrical voltage, hence the importance of developing conductive materials. The EAP material selected for the study is silicone rubber. Thus, the formulation of composite materials from a silicon elastomer matrix loaded with conductive carbon particles (graphite, graphite nanosheets and multi-wall carbon nanotubes) is the route followed for the formation of deformable electrodes.

On the use of wood charcoal filler to improve the properties of natural fiber reinforced polymer composites

Abstract This study aims to analyze the incorporation of widely available, cheap and biobased waste material such as wood charcoal which is used as filler in natural fiber reinforced polymer composites. Jute woven fabric (1 × 1 plain weave) was used as a natural fiber reinforcement, unsaturated polyester resin was used as matrix material, and wood charcoal powder used as bio-filler to manufacture various composite material formulations of 25% fiber weight fraction. The wood charcoal filler loadings were 4, 8, 12, 16 and 20 wt% in the polymer matrix of the composites. The developed composite formulations were tested in terms of mechanical and physicochemical properties. Improved tensile properties were revealed with a 4 wt% filler modification, compared to the reference (unmodified) polymer composite. Nonetheless, further increase of filler (8–20 wt%), led to lower mechanical properties. Thermogravimetric analysis showed increased thermal stability of the 4 wt% charcoal filler modified composite compared to the reference one.

Polymer-Based Composites: An Indispensable Material for Present and Future Applications

Right from the early days, polymer materials have been discovered as being beneficial for various applications but a poor understanding of these materials greatly handicapped their usage. However, with a change in this trend, polymer materials have gradually displaced other materials in most applications. In recent times, due to improved research and knowledge, polymer-based materials are the first choice materials for several applications and are now replacing other materials rapidly. More advanced materials from polymers are being developed daily as a substitute for other materials even in areas where polymers are considered not to be suitable in the time past. More recently, polymers have replaced metals and ceramics in applications like constructions, aerospace, automobiles, and medical. It is no doubt that this trend will continue due to the inherent properties of polymers and sustainability potential. Today, most of the limitations of polymers are being taken care of in the formulation of composite materials. Besides, the adaptation to positive environmental influence is being handled by scientists and researchers. Hence, this review reveals core areas of application of polymer-based composites and the significance of these materials to the advancement of humanity.

Dental composite resins with low polymerization stress based on a new allyl carbonate monomer

The objective of this study was to synthesize a diallyl carbonate monomer, allyl(2-(2-(((allyloxy)carbonyl)oxy)benzoyl)-5-methoxyphenyl) carbonate (BZ-AL), and to evaluate its effect as Bis-GMA diluent in the formulation of photopolymerizable dental composite resins. The chemical structure of BZ-AL monomer was determined by means of H1 NMR, C13 NMR and FTIR spectroscopies. An experimental composite comprising a mixture of Bis-GMA and BZ-AL monomers and silanized inorganic filler was formulated. Experimental material was compared with a control composite formulated with Bis-GMA/TEGDMA. Double bond conversion, polymerization kinetics, volumetric shrinkage, polymerization stress, and flexural properties were investigated. The data were analyzed through a Student t-test (α = 0.05). Flexural strength of the experimental materials with BZ-AL monomer showed a statistically significant increase (p < 0.001). The experimental composite has a lower polymerization rate than the control composite, on the other hand, the experimental composite resin has the highest degree of double bond conversion. There are no differences in the polymerization shrinkage of the composites, however, the polymerization stress of the experimental materials was 50% lower than the control resin. Finally, the cell viability test showed that the experimental resins formulated with the BZ-AL monomer was not cytotoxic. Due to its characteristics, BZ-AL monomer is potentially useful for the formulation of composite materials with applications in dentistry.

Application of preference selection index method in performance based ranking of ceramic particulate (SiO2/SiC) reinforced AA2024 composite materials

In this research article, ceramic particulate (SiO2/SiC) reinforced AA2024 alloy composite material formulation has been prepared via semi-automatic stir casting technique following industrial standard practice. The samples specimens have been prepared as per ASTM standard dimensions and the physical, mechanical and wear performance test were performed. The obtained test results have higher confidence level (95%) and the same has been used to rank the composite materials of the formulation using Preference Selection Index (PSI) method (a Multi-Criteria-Decision-Making (MCDM) tool) which is simple to compute and understand. This enables a practicing engineer to rank the designed materials via optimizing material properties like tensile strength, flexural strength, impact strength, wear resistance, density etc. It has been observed that the aluminium alloy composite incorporated with an equal presence of both ceramics shows best properties and also ranked highest by PSI method. Hence, such techniques may be used for decision making successfully in the selection of materials.

Evaluation of bio-based monomers from isosorbide used in the formulation of dental composite resins

The objective of this study was to synthesize two bio-based monomers from isosorbide, the bis(allylcarbonate) isosorbide (IBAC) and the bis(methacrylate) isosorbide (IBM), and to evaluate its effect as Bis-GMA diluents in the formulation of photopolymerizable dental composite resins. The chemical structure of both bio-based monomers was determinate by means H1 NMR, C13 NMR and FTIR spectroscopies. Experimental composites comprising Bis-GMA/IBAC or Bis-GMA/IBM were formulated using 65 %wt of silanized inorganic filler. Experimental materials were compared with a control composite formulated with Bis-GMA/TEGDMA. Double bond conversion, polymerization kinetics, volumetric shrinkage, water sorption, solubility, and flexural properties were investigated. The data were analyzed by one-way ANOVA and Tukey test (α = 0.05). Flexural strength of the experimental materials was similar to the control (p = 0.733). Bis-GMA/IBM achieved the highest values of elastic modulus (p = 0.135). Bis-GMA/IBAC composite achieved the highest values of degree of conversion, while the values of Bis-GMA/IBM composite were similar to the control (p > 0.05). There were no differences in the polymerization shrinkage of the composites, however, the polymerization stress of the experimental materials was lower (p < 0.05). Finally, the cell viability test showed that the experimental resins formulated with the bio-based monomers were not cytotoxic. Due to its characteristics, IBAC and IBM monomers are potentially useful for the formulation of composite materials with applications in dentistry.

Materials and Technologies Ensuring Environmental Safety of Reconstruction and Overhaul of Trunk Pipelines

The paper presents an overview of the studies of Russian and foreign scientists exploring the issues of reliable operation of trunk pipelines transporting oil and gas. It is found that subsea pipeline networks pose a greater danger in terms of their functional failures and environmental effects and appear more prone to stress corrosion cracking. Certain materials and technologies are brought into focus to demonstrate that their use allows curbing the environmental expansion or ensures the reliable operation of oil and gas pipelines. It is noted that one of the most promising methods for reconstruction and overhaul of trunk pipelines provide for the application of composite materials to the internal surface of a damaged pipes. The appropriate formulation of composite materials depends on the condition of the internal pipeline cavity. Also, there are scientific breakthroughs which may serve to reduce corrosion activity of clayey soils. Stress is laid on the importance of innovations in the development of technologies and materials ensuring the maintenance of ecological balance in the areas where oil and gas transmission networks operate.

Influence of the Individual Layers of Laminate on the Final Static Response

The thesis based on a model example, describes in details the formulation of composite materials in simulation software. Furthermore, it points out the influence of the material properties orientation in composite materials by means of a comparison between two geometrically identical models with different material properties orientations. Changes in stress of layers were achieved through changes in orientation. The results of the achieved maximum stress levels are systematically processed in the table, in which the influence of orientation across the individual layers may be clearly observed.

Development of recycled polymer composites for structural applications

This paper is concerned with the formulation of composite materials for structural or semistructural applications using thermoplastic polymer waste. The mechanical and thermal properties of a proprietary blend of recycled polymers with a range of different fillers were investigated. The effect varied with the aspect ratio of the filler and the mode of loading. Spherical calcium carbonate gave a marginal improvement in modulus. Plate-like mica produced a significant increase in modulus without reduction in strength. Glass fibres caused a significant increase in modulus and strength while decreasing the linear coefficient of thermal expansion. Hybrid systems containing glass fibre and a lower aspect ratio filler were also investigated to obtain a material system which combines high properties and reasonably low cost. It was found that addition of small quantities of mica to glass fibre reinforced blends exhibited a significant synergy in tensile strength and modulus.

Jordanian Clay-Based Heat Insulator Composites: Mechanical Properties

In this study formulation of composite materials was made using different types and compositions of Jordanian fillers of virgin, untreated bentonite, and feldspar. Unsaturated polyester liquid blended with the filler with a given polyester/filler ratio was transformed into solid upon thermo-set process using chemical reagents to initiate the thermo-set process, and later control the propagation and termination steps. The solid samples produced were then subjected to mechanical, thermal conductivity, and water absorption tests to come up with a product formulation having best or optimum properties in terms of previously tested characteristics. In this paper, the results of the mechanical tests will be presented. In brief, it was found that mechanical properties did improve with increasing clay weight percentage up to 60 wt%. Beyond 60 wt% the product formulation was found to be inconsistent and non-reproducible. Furthermore, it was found that a composite material based on a certain type of clay (with highest content of Al2O3 and SiO 2), possessed superior characteristics in terms of mechanical properties and compared with calcium-carbonate-containing, polyester-based composite materials.

Fracture Toughness and Fatigue Crack Propagation Rate of Short Fiber Reinforced Epoxy Composites for Analogue Cortical Bone

Third-generation mechanical analogue bone models and synthetic analogue cortical bone materials manufactured by Pacific Research Laboratories, Inc. (PRL) are popular tools for use in mechanical testing of various orthopedic implants and biomaterials. A major issue with these models is that the current third-generation epoxy-short fiberglass based composite used as the cortical bone substitute is prone to crack formation and failure in fatigue or repeated quasistatic loading of the model. The purpose of the present study was to compare the tensile and fracture mechanics properties of the current baseline (established PRL "third-generation" E-glass-fiber-epoxy) composite analogue for cortical bone to a new composite material formulation proposed for use as an enhanced fourth-generation cortical bone analogue material. Standard tensile, plane strain fracture toughness, and fatigue crack propagation rate tests were performed on both the third- and fourth-generation composite material formulations using standard ASTM test techniques. Injection molding techniques were used to create random fiber orientation in all test specimens. Standard dog-bone style tensile specimens were tested to obtain ultimate tensile strength and stiffness. Compact tension fracture toughness specimens were utilized to determine plane strain fracture toughness values. Reduced thickness compact tension specimens were also used to determine fatigue crack propagation rate behavior for the two material groups. Literature values for the same parameters for human cortical bone were compared to results from the third- and fourth-generation cortical analogue bone materials. Tensile properties of the fourth-generation material were closer to that of average human cortical bone than the third-generation material. Fracture toughness was significantly increased by 48% in the fourth-generation composite as compared to the third-generation analogue bone. The threshold stress intensity to propagate the crack was much higher for the fourth-generation material than for the third-generation composite. Even at the higher stress intensity threshold, the fatigue crack propagation rate was significantly decreased in the fourth-generation composite compared to the third-generation composite. These results indicate that the bone analogue models made from the fourth-generation analogue cortical bone material may exhibit better performance in fracture and longer fatigue lives than similar models made of third-generation analogue cortical bone material. Further fatigue testing of the new composite material in clinically relevant use of bone models is still required for verification of these results. Biomechanical test models using the superior fourth-generation cortical analogue material are currently in development.

The Ingrowth of New Bone Tissue and Initial Mechanical Properties of a Degrading Polymeric Composite Scaffold

Trabecular bone deficiency causes a dilemma at surgery in a variety of clinical situations, including trauma, tumor resection, and reconstruction. A synthetic material to replace trabecular bone would be biocompatible, provide temporary mechanical strength to the reconstructed region, and serve as a scaffold upon which new bone could grow (i.e., osteoconduction). In addition, it should serve as a carrier for osteoinductive biomolecules, degrade into nontoxic materials that the body can excrete via normal metabolic pathways, and allow the new bone to remodel along lines of local stress. A particulate filled composite based on an unsaturated linear polyester was designed as a candidate material for this application. The components are mixed with a monomer that cross links the double bonds of the unsaturated polyester. Degradation occurs via hydrolytic degradation of the backbone polymer's ester linkages. This strategy of prepolymer synthesis via condensation polymerization in the laboratory followed by cross linking the unsaturated prepolymer via radical polymerization at surgery offers design flexibility. The radical polymerization allows curing during surgery to facilitate reconstruction of various shaped defects. The laboratory synthesis of the prepolymer allows alterations of its composition and physical properties to effect desired properties in the resulting composite. This study investigates the effect of several composite material formulations on the in vitro mechanical properties and the associated in vivo histologic characteristics of the resulting material. The prepolymer molecular weight, presence of a leachable salt, and amount of cross linking monomer had strong effects on the resulting strength and modulus of the composite. These strengths were on the order of 5 MPa, a magnitude appropriate for consideration of the material as a temporary trabecular bone substitute. The in vivo studies in a rat proximal tibia model demonstrated progressive growth of new bone against the receding surface of the degrading material, and ingrowth of new bone trabeculae into the interior of the degrading specimen. The specimen was also well integrated with the surrounding bone, with no internal fibrosis. There was an absence of a foreign body inflammatory response to the presence of this material over a 5-week time span. This material may thus be an attractive candidate for temporary replacement of trabecular bone, facilitating both osteoconduction and osteoinduction.

A micromechanics model for composites under fatigue loading

Based upon an average stress formulation of composite materials derived from the Mori-Tanaka method, a fatigue criterion is established. The criterion is at the micromechanics level, and addresses the failure of all the constituents of the composite and represents the interactions between the constituents of the composite by involving the volume fraction, the properties of the constituents and the interfacial bond. Predictions of the S N curves for E-glass/epoxy laminae under off-axis loading are compared with the existing experimental data.

Nonlinear buckling analysis of discretely stiffened composite cylindrical shells

A nonlinear theoretical analysis for predicting the buckling and postbuckling loads of discretely stiffened composite cylindrical shells is presented in this paper. Geometric and material nonlinearities, the effects of transverse shear and initial imperfection are considered in the analytical model. The composite material formulation is valid with the nonlinear behavior described by the modified Romberg-Osgood relation and Hill's criterion combined in an elastic-plastic model. The prebuckling analysis is obtained using the principle of virtual work, with the postbuckling bifurcation analysis based on Huchinson's criterion. Some shell examples calculated numerically show that the theoretical analysis is in good agreement with the experimental results and other known solutions. Thus, the nonlinear theory and analysis procedure described herein can be used as an aid in the design process of composite or isotropic cylindrical shells with or without stiffeners and rings.

Buckling, postbuckling, and crippling of shallow-curved composite plates with edge stiffeners

Stress-energy density A theoreticai/anal ytical capability for prediction of buckling, p ostbuckling, and crippling ,af metal and composite shallow curved plates is presented. The theoretical model accounts for both geometric and material nonlinearities. The composite material formulation is valid fgr anisstropic lamina with the nonlinear behavior described by Ramberg-Osgood inplane and matrix stress-strain relations. Transverse shear effects are 4153 included. Correlations with available metai and composite experimental data confirm the accuracy qf the p resent approach. Stress-energy density of the th lamina as a function of inplane stresses in material coordinates Stress-energy denstiy of kth layer of matrix m aterial Inplane shear moduius relative ts material axes coordinates Yatrix material shear modulus and stiffener average shear modulus, respectively Yomenclature Laminate thickness

Protective coatings for SiC fibers in contact with nickel alloys

1. SiC vigorously reacts with Ni-Cr base alloys and cannot be used in direct contact with them. 2. TiN and Al2O3 coatings applied to SiC fibers are compatible with Ni-Cr base alloy matrices and may be utilized for barrier protection in the formulation of composite materials. 3. Si3N4 and BNC coatings react with Ni-Cr base alloys and are therefore unsuitable for operation at high temperatures.

An experimental radiopaque composite material.

Numerous physical properties of a new reinforced resin were found to be similar to those obtained with earlier composite material formulations.