Shell Filler Research Articles

Mediating dielectric/breakdown conflict in polydopamine@HfB2 nanorod-filled polymer composites from rational meaty-sandwich structure

The contradiction between high permittivity and breakdown strength in dielectrics is acknowledged. Although a sandwich structure endows the nanocomposites with ultrahigh breakdown strengths, the permittivity is limited ascribed to series connection of layers. In this work, a novel strategy from “meaty-sandwich” food was utilized to prepare the multi-layer polymer nanocomposites with finely balanced high permittivity and breakdown strength. HfB2 nanorods, BaTiO3 nanoparticles, and BN nanosheets were used as fillers. HfB2 were surface-coated by polydopamine to gain the core–shell nanorods. High-content middle-layer composite results in a large dielectric response, while low-content bilateral-layer composite leads to high breakdown strength. Tri-layer composites with core–shell filler show high breakdown strengths. Five-layer composite with four high-insulation thin layers exhibits an ultrahigh breakdown strength and favorable permittivity. Breakdown mechanisms of composites were proposed. The best tri-layer composite shows a high permittivity of ~ 136@100 Hz and breakdown strength of ~ 263 MV m−1. This work might pave a road for fabrication of promising dielectrics.

The effect of walnut processing by-product filler on properties of plywood

In this study, walnut processing by-product was served as filler to make three-layer plywood, and the physical-mechanical properties were also discussed. The results showed that the formaldehyde emission of plywood corresponding to walnut shell and walnut dregs decreased by 0.0542 mg/L and 0.066 mg/L, respectively. The properties of plywood filled with walnut dregs are better than that of walnut shell filler, and the formaldehyde emission of the corresponding plate is lower. At the same time, compared with flour, the wet bond strength of walnut shell plywood increased by 0.0332 MPa, and that of walnut dregs plywood decreased by 0.123 MPa, but they all met the national standards.

The potential of rising husk fiber/native sago starch reinforced biocomposite to automotive component

This work aims to examine the mechanical and thermal behavior of rising husk fiber/starch reinforced epoxy polymer composites. Experiments are carried out to study the effect of fiber and filler volume percentage on the mechanical, and thermal behavior of epoxy-based polymer composites. The volume of fibre and filler is varied by 10%,20%,30%, 40%, and starch 5% and 10% and 1.5%, respectively. The specimens are fabricated by using hand layup technique. The specimens are expurgated according to ASTM standards. The effects of rising husk fiber and filler were examined under different thermal conditions. The mechanical results show that the addition of fiber increased the impact characters of epoxy resin, whereas the addition of starch shell filler increased the termal conductivity of the composite. We found that the results show that the stacking sequences of rising Husk/starch fibers have a significant impact on thermal conductivity. Composites with the stacking sequence mode RH40 with 15 % starch exhibit the highest thermal conductivity 2.6 W/m·K an enhancement of 472,72% over the thermal conductivity of the PC resin (0.55 W/m·K) it is significant

Impact behavior of pine needle fiber/pistachio shell filler based epoxy composite

Natural filler/fiber based composites are material focusing on the use of natural reinforcement material for fabrication process. In present research two different composites are developed using (i) pine needle fiber and epoxy (ii) pistachio shell filler and epoxy. Impact strength of developed composites is studied which shows that with addition of pistachio shell filler and pine needle fibers in composites, there is increase in impact strength as compared to neat epoxy sample. In addition, hybrid composite with natural filler and pine needle fiber has shown the highest impact strength of 23.33 kJ/m2. Investigating samples further in different conditions (petrol, kerosene, water) for impact strength, research shows that there is substantial decrease in strength in comparison to the samples subjected to ambient conditions.

Investigation on thermo-mechanical characteristics of treated/untreated Portunus sanguinolentus shell powder-based jute fabrics reinforced epoxy composites

The current study deals with the effective usage of Portunus sanguinolentus shell, which is a solid waste in the seafood industry. This Portunus sanguinolentus shell waste was powdered and used as untreated fillers in jute fabrics reinforced epoxy composites. Then Portunus sanguinolentus shell waste powder was treated with chemicals to perform fat removal, deproteination, decarbonization and deacetylation to obtain treated Portunus sanguinolentus shell filler. Three different composites were developed with traditional hand layup process consisting of four layers jute fabrics that were filled with 10 wt% untreated Portunus sanguinolentus shell filler, chemical treated 10 wt% Portunus sanguinolentus shell filler and unfilled one. The thermo-mechanical and fracture morphologies were assessed by tensile, flexural, compression, shear, impact, hardness thermogravimetric analysis, Fourier-transform infrared spectroscopy and scanning electron microscopy analysis. The results showed an increase in the thermo-mechanical property of chemical-treated Portunus sanguinolentus shell powder-filled jute fabrics-based epoxy composite. This phenomenon is due to the increase in the chitosan, mineral contents and decrease in the organic content in the Portunus sanguinolentus shell powder due to chemical treatment, thus enhancing the bonding between the filler and fiber matrix with reduction of the void. A showcase stand was developed with the best performer, as an attempt in the perfection of application. The application is then analyzed using ANSYS to predict the deformation behavior when subjected to 0.25 kg, 0.5 kg and 1 kg loads.

Study of influence of process parameters in drilling of glass fibre reinforced polymer composite with clam shell filler

Abstract This study focuses on assessing the effects of drill diameter, spindle speed and feed rate on delamination factor (both peel up and push out) and surface roughness in drilling of three different composite plates with 0, 10 and 20 wt% of clam shell powder filler in glass fibre reinforced composite using twist drill bit. Taguchi’s experimental design approach is used to develop a parametric analysis of drilling process. Drill diameter is the most effective parameter for delamination of composite followed by feed rate and spindle speed. The filler content has influence in determining the surface roughness.

Experimental study on the influence of fibre surface treatments and coconut shell powder addition on the compressive strength, hardness and tribological properties of sisal fibre-natural rubber composites

In the present environment scenario, toxic wastes and their disposal is a major issue. Use of natural materials is the viable solution for this problem. This work aims to design and develop an elastomer composite using natural materials - natural rubber composite reinforced with sisal fibres. Since rubber components are essentials in industrial products, the developed material has lot significance. Six composites made with sisal fibres with various surface modifications and a 10%w/w coconut shell filler powder in natural rubber matrix. Sisal fibres used are raw fibre, alkalised fibres, rubber pre-impregnated raw fibres and rubber pre-impregnated alkalised fibre. The specimens tested for wear resistance, compressive strength and hardness. Maximum wear resistance exhibited by alkalised pre-impregnated sisal-rubber composite, followed by raw pre-impregnated-coconut shell powder-rubber composite. The hardness of raw sisal-rubber and raw pre-impregnated fibre composites improved by 228% than pure rubber (25 Shore A). Compressive strengths also showed improvements.

The strengthening of woven jute fiber/polylactide biocomposite without loss of ductility using rigid core–soft shell nanoparticles

Some efforts have been made to strengthen the environment friendly natural fiber-reinforced polylactide composite (NFPC), but common approaches impair its ductility. This paper successfully synthesized the rigid-soft core–shell nanoparticles which are feasible to simultaneously improve the strength and toughness of NFPC. The core–shell structure was molecularly designed to act the nano-silica and poly (butyl acrylate) rubber as rigid inner core and soft outer shell, respectively. Furthermore, the devised active functional groups at the end of core–shell filler also interact with polylactide (PLA) matrix to form strong interface. The effect of core–shell nanoparticle on crystalline, thermal and mechanical properties of NFPC was investigated. The results showed that the core–shell nanofiller can facilitate to form the more complete crystalline grain of PLA matrix and the thermal stability improvement of NFPC. More attractively, the addition of the rigid-soft core–shell nanoparticle enhanced the strength and stiffness of NFPC without sacrificing its elongation at break. Finally, the toughness improvement mechanisms and synergistic effect of core–shell nanoparticles were illustrated via field emission scanning electron microscope. It indicates that the micro-cracks, shear band and fibration of the matrix induced by the core–shell filler are the main causes of toughness improvement.

Mechanical, wear and thermal behaviour of hemp fibre/egg shell particle reinforced epoxy resin bio composite

The aim of this work is to examine the mechanical, tribological, and thermal behaviour of hemp fibre reinforced egg shell epoxy polymer composites. Experiments are carried out to study the effect of fiber and filler volume percentage on mechanical, wear, and thermal behaviour of epoxy based polymer composites. The volume of fibre and filler is varied by 30%, 40%, and 50% and 0.25%, 0.5%, and 1.0%, respectively. The specimens are fabricated by using hand layup technique. The specimens are expurgated according to ASTM standards. The mechanical tests such as hardness, tensile, impact and flexural strength are evaluated and abrasive wear behaviour of the specimen was investigated using a pin-on-disc machine. The thermal stability was evaluated using a thermo gravimetric analyzer. The effects of hemp fibre and filler were examined under different mechanical and thermal conditions. The mechanical results show that the addition of fibre increased the load bearing characters of epoxy resin, whereas the addition of egg shell filler increased thermal stability of the composite.

Waste walnut shell as an alternative bio-based filler for the EPDM: mechanical, thermal, and kinetic studies

In recent years, bio-based polymers and fillers are attracting the attention of researchers due to strong concerns on environmental friendly production of rubbers. In this study, the waste walnut shell was used as an alternative filler for ethylene–propylene–diene monomer rubber (EPDM). The surface of the waste walnut shell was modified with bis[3-(triethoxysilyl)propyl] tetrasulfide to achieve a better interfacial interaction with EPDM matrix. Effect of different parameters on mechanical, thermal, and rheological properties of EPDM/waste walnut shell filler composite was investigated. It was seen that the increase of walnut shell content led the increase in tensile strength. Moving die rheometer tests have shown that the addition of walnut shell improved the torque value. In addition, the thermal tests were shown that using the waste walnut shell as filler results with no considerable difference in the thermal properties. Swelling test and cross-link density analyses showed that walnut shell addition has no negative effect on cross-link density. It was concluded that the waste walnut shell could be an effective filler with its advantages of bio-based and biodegradable.

Thermal, mechanical and physical properties of nanoegg shell particle-filled epoxy nanocomposites

This work involves the study of the thermal, mechanical and physical properties of epoxy filled with nanoegg shell particles. Nanoegg shell particles of near uniform size and shape were prepared by high-speed ball milling technique. The influence of nanoegg shell particle concentration (1 to 5 wt.%) on epoxy curing rate, thermal stability, dynamic mechanical properties and the tensile, hardness, impact and water uptake properties was evaluated. The result showed improvement in most of these properties except for storage modulus in the rubbery phase. Microscopic examination revealed strong particle–matrix adhesion strength, with optimum improvement of all properties at 2 wt.% nanoegg shell filler concentration.

Effect of Clams Shell in Impact Properties of Jute Epoxy Composite

The present study attempts to explore the possibilities of utilizing marine waste like Clams Shell as filler material in jute fibre reinforced composites. It's use in composites would address the utilization of waste material as filler material into a value added product. In order to determine the impact property of this polymer composites with jute fibre and clams shell filler (0, 5, 10 wt%) content, impact test is performed by using Izod impact tester. The hand layup technique is used for the preparation of the composite samples. It is found that introduction of fillers on jute fibre reinforced composite results in reduction of its impact strength.

Comparing Impact Behavior of Natural Fiber with Termite Mound and Egg Shell Filler added Reinforced Composite

Comparing Impact Behavior of Natural Fiber with Termite Mound and Egg Shell Filler added Reinforced Composite

Mechanical Property Evaluation of Palm/Glass Sandwiched Fiber Reinforced Polymer Composite in Comparison with few natural composites

Natural fibers available plenty can be used as reinforcements in development of eco friendly polymer composites. The less utilized palm leaf stalk fibers sandwiched with artificial glass fibers was researched in this work to have a better reinforcement in preparing a green composite. The commercially available polyester resin blend with coconut shell filler in nano form was used as matrix to sandwich these composites. Naturally available Fibers of palm leaf stalk, coconut leaf stalk, raffia and oil palm were extracted and treated with potassium permanganate solution which enhances the properties. For experimentation four different plates were fabricated using these fibers adopting hand lay-up method. These sandwiched composite plates are further machined to obtain ASTM standards Specimens which are mechanically tested as per standards. Experimental results reveal that the alkali treated palm leaf stalk fiber based polymer composite shows appreciable results than the others. Hence the developed composite can be recommended for fabrication of automobile parts.

Degradation Test of Natural Rubber/Chitosan Composite

Degradable materials from 20wt% chitosan loading and natural rubber (CS/NR) were prepared by solution casting without surface treatment to study their thermal and mechanical properties after degradation test in aging condition. The test was done in an acrylic degradation box with 600 W light and high humidity for accelerate degradation condition. Samples included high ammonia concentrated latex (HA) with no filler, fresh latex (FL) with no filler, HA with chitosan filler, FL with chitosan filler, and natural rubber with shrimp shell filler to compare the result with chitosan filler. After degradation test, thermal properties from TGA both before and after degradation showed that the fillers effected on these composite materials. TGA result of CS/NR composite with aging at temperature 100 °C for 10 h and 20 h showed that chitosan slightly effected on thermal stability of composites when compare to natural rubber. SEM images were compared before and after degradation of HA and FL with no filler, chitosan filler, and shrimp shell. It was clearly seen that the samples degraded as the shape and size were changed. Tensile testing values showed that longer aging time could lead to the degradation in CS/HA and lower the tensile strength.

Synergy of cashew nut shell filler on tribological behaviors of natural-fiber-reinforced epoxy composite

Abstract The aim of this work is to investigate the adhesive dry sliding wear and friction performance of biodegradable cashew nut shell (CNS)-filler-reinforced epoxy composite. The composites are prepared with 5, 10, 15, 20, 25, 30, 35, and 40 weight content of CNS filler. Experiments were conducted to perform the required measurements. The results show that the specific wear rates and frictional coefficients are found lower at 30% untreated and treated CNS-containing composites. The NaOH-treated CNS filler composites showed low wear and frictional performance compared to raw CNS. The back film formation was associated with the predominant wear mechanics with the formation of fine debris on the worn surface and counterface.

Processing and Evaluation of Mechanical Properties of Sugarcane Fiber Reinforced Natural Composites

In the present work, the natural composites based on sugarcane bagasse fiber and/or coconut shell powder were processed using hand lay-up technique. The matrix selected was polyester. Three different types of composites were considered: polyester matrix + sugarcane fiber, polyester matrix + sugarcane fiber + metal mesh and polyester matrix + sugarcane fiber + coconut shell filler. The sugarcane fibers were used in three forms: (1) chemically treated by NaOH, (2) chemically treated by HCl, and (3) untreated condition. In total, 9 types of composites were developed and studied for tensile, flexural and impact properties. The fracture surface of the tensile and flexural test samples was examined with the aid of scanning electron microscope to understand the bonding characteristics and the mode of failure. The key-findings from the present work are: (1) the composites reinforced with the NaOH treated sugarcane fiber and the metal mesh show superior tensile and impact properties whereas the composites reinforced with the NaOH treated sugarcane fiber show the best flexural properties, (2) NaOH treatment of sugarcane fibres has a significant effect in improving the mechanical properties by surface modification of fibres through OH− functional groups. In contrast, HCl treatment of sugarcane deteriorates the surface of the sugarcane by absorbing the electrons. The damaged surface results in weak bonding causing poor mechanical properties, (3) From the SEM analysis of the surface of the sugarcane fiber, it may be concluded that the surface condition of the sugarcane fibres decide the bonding with the matrix. The fiber pull-outs and porosities are less in the NaOH treated sugarcane reinforced composites. The fiber failure is the main mechanism of failure in the tensile test whereas the fiber debonding from the matrix is the main source of failure in the flexural test.

Epoxy composites with ceramic core–shell fillers for thermal management in electrical devices

In this work, a novel core–shell material has been manufactured in order to enhance the thermal conductivity of epoxy‐based composites. The polymer derived ceramics technique has been used to produce fillers whose core is composed of a standard material – silica, and whose outer layer consists of a boron nitride or silicon nitride shell. The synthesized filler was characterized by infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy coupled with an energy dispersive spectroscopy analysis. The successful formation of core–shell structure was proven. Composite samples based on an epoxy resin filled with 31 vol% of synthetized core–shell filler have been investigated in order to determine the effective thermal conductivity of the modified system. The resulting core–shell composite samples exhibited improvements in thermal conductivity of almost 30% in relation to standard systems, making them a promising material for heat management applications. Additionally, the temperature dependence of the thermal conductivity was investigated over a broad temperature range indicating that the thermal behavior of the composite with incorporated core–shell filler is stable. This stability is a crucial factor when considering the potential of using this technology in applications such as electronics and power systems. Copyright © 2017 John Wiley & Sons, Ltd.

Effect of Hybrid Talc-Basalt Fillers in the Shell Layer on Thermal and Mechanical Performance of Co-Extruded Wood Plastic Composites.

Hybrid basalt fiber (BF) and Talc filled high density polyethylene (HDPE) and co-extruded wood-plastic composites (WPCs) with different BF/Talc/HDPE composition levels in the shell were prepared and their mechanical, morphological and thermal properties were characterized. Incorporating BFs into the HDPE-Talc composite substantially enhanced the thermal expansion property, flexural, tensile and dynamic modulus without causing a significant decrease in the tensile and impact strength of the composites. Strain energy estimation suggested positive and better interfacial interactions of HDPE with BFs than that with talc. The co-extruded structure design improved the mechanical properties of WPC due to the protective shell layer. The composite flexural and impact strength properties increased, and the thermal expansion decreased as BF content increased in the hybrid BF/Talc filled shells. The cone calorimetry data demonstrated that flame resistance of co-extruded WPCs was improved with the use of combined fillers in the shell layer, especially with increased loading of BFs. The combined shell filler system with BFs and Talc could offer a balance between cost and performance for co-extruded WPCs.

Core–shell SiC/SiO2 whisker reinforced polymer composite with high dielectric permittivity and low dielectric loss

A polymer composite with high dielectric permittivity and low dielectric loss was successfully fabricated by embedding core–shell structure whisker in polymer matrix. The novel core–shell structure of silicon carbide/silicon dioxide whisker (SiC/SiO2-W) filler was prepared via a one-step air-exposure calcination treatment of original SiC whisker (SiC-W). The effects of semiconductor-insulator core–shell filler on morphology structure, mechanical properties, dielectric and electrical properties of poly(vinylidene fluoride) (PVDF) composite were investigated. Compared with SiC-W/PVDF composite, SiC/SiO2-W/PVDF composite shows stronger mechanical properties, and dramatically suppressed dielectric loss and conductivity while remains high dielectric permittivity. Furthermore, the dielectric and electrical properties of the composite can be further optimized by adjusting the shell thickness. Especially, the composite with SiO2 thickness of 6–7nm presents the best integrative dielectric and electrical properties, which exhibits a dielectric permittivity of 2230.3 and a dielectric loss of 0.86 at 100Hz.