Epoxy-based Polymer Composites Research Articles

Effect of alkali treatment on mechanical and water absorption properties of biodegradable wheat-straw/glass fiber reinforced epoxy hybrid composites: A sustainable alternative for conventional materials

Fiber-reinforced polymer composites are preferred over conventional materials because of their superior strength and modulus. Previously limited due to high manufacturing costs, synthetic fibers have been replaced by some natural fibers, such as waste wheat straw fibers. Here, epoxy-based polymer composites' mechanical and physical properties have been investigated, focusing on fiber weight ratios for both treated and untreated fiber. The research found that treated fibers display more effective mechanical qualities than untreated fibers, with a higher tensile strength of 54.4 MPa. The untreated Wheat Straw-Glass fiber reinforced composite has a less tensile strength of 26.3 MPa (10 wt% fiber). Pure resin-based composite has the most minor tensile strength at 1.52 MPa. The highest flexural strength obtained for hybrid composite is 88.76 MPa for treated fiber with epoxy resin and 49.6 MPa for untreated 30 wt % fiber. At the same time, the sole epoxy resin composite has the lowest value of 10.60 MPa. Untreated fiber (30 wt%) has the highest impact energy of 8J. Untreated wheat straw fiber absorbs more water due to its hydrophilic nature. In contrast, treated fiber exhibits better bonding and minimal water content, and the sole epoxy resin composite exhibits hydrophobic properties, resulting in less water absorption. The treated fiber displays better bonding than the untreated fiber throughout the SEM analysis. Wheat Straw fiber is mainly used for biodegradable plastic formation, housing construction, building materials, etc.

Carbon Fiber and Carbon Fiber Reinforced Epoxy Composites for Automotive Applications-A Review

Lightweight materials have recently received much attention for the fabrication of various components for industrial usage, particularly in the automotive and aerospace fields. Nowadays, though, recycling epoxy-based composite at the end of its life is very complicated but due to its lightweight and enhanced properties "fiber-reinforced" epoxy based polymer composites are most preferred materials instead of conventional heavy metals. The composites based on epoxy resins reinforced with high-performance fibers such as carbon fiber (CF) are in extensive use for industrial and structural applications. Moreover, Thermoplastics are less expensive, simple to work with and simple to recycle but they can’t give desired properties like Thermosets. The current study encompasses about CF and multiple attempts done over the decades to enhance the mechanical attributes of CF-reinforced thermo-set (epoxy) based composites and to understand the part of many parameters on their performance.

Mechanical and tribological characterization of graphene nanoplatelets/Al2O3 reinforced epoxy hybrid composites

This study aimed to determine the effects of varying Aluminum oxide (Al2O3) and Graphene Nanoplatelets (GNP) concentrations on epoxy-based polymer composites’ mechanical and tribological characteristics. Al2O3 (1 to 5 wt.%) and GNP (0 to 1 wt.%) reinforced epoxy matrix composites were produced with sonication and stirring magnetic route. Mechanical, microstructural and tribological properties of composites were investigated via X-ray diffraction (XRD), Archimedes’ Method, Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDX), Raman spectroscopy, hardness, impact, tensile, compressive and wear tests. The highest ultimate tensile strength and compressive strength were found at 62.83 and 137 MPa for 3 wt.% reinforced Al2O3 epoxy matrix composites, and it was observed that there was a 38% and 17% increase compared to neat epoxy, respectively. The highest impact strength was found for 3 wt.% Al2O3 and 1 wt.% GNP-reinforced composites and increased by 19% compared to neat epoxy. The best hardness was found for 3 wt.% reinforced Al2O3 and 0.25 wt.% GNP-reinforced composite, and there was a 22% increase in hardness compared to neat epoxy. Also, the highest wear resistance (1.686x10−6 mm3/Nm) and lowest Coefficient of Friction (COF, 0.13755) were determined for the same specimen.

Tribological and mechanical analysis of hybrid epoxy based polymer composites with different in situ liquid lubricants (silicone oil, PAO and SN150 base oil)

This study compares the tribological, thermal and mechanical properties of epoxy-based composites with solid fillers (ultrahigh molecular weight polyethylene, molybdenum disulphide), and different in situ liquid lubricants in different volume proportions. Liquid lubricants used in this paper are three types of silicon oil with different viscosities, base oil and polyalphaolefins (PAO). The base oil-epoxy composite showed superior tribological performance among the three. The coefficient of friction of 0.1 and specific wear rate in the range of 10−7 mm3/Nm were obtained at an apparent pressure of 0.611 MPa. Transfer film formation with oil pockets on both the tribo-pair surfaces was identified as the main friction and wear reduction mechanisms. The surface of epoxy became hydrophobic, reducing adhesive interaction and friction.

Mechanical characterization of polymer composite reinforced with Bio-fillers

In order to attain environmental protection, organic composite materials are increasingly replacing plastics. The goal of this study was to create composites by using discarded tamarind seed powder (TP) as a bio-filler reinforcement material into an epoxy-based polymer matrix. The epoxy-based polymer composites were fabricated by altering the filler proportions from 10 to 20% by the weight of epoxy matrix. A computerized universal testing machine (CUTM) had been used to assess the impact of reinforced TP content on the mechanical characteristics (tensile, flexural and impact strength) of the polymer composites. The mechanical characteristics of the polymer composite was considerably climbed-up as the bio-filler content increased from 10% to 40% and unexpectedly dropped at the weight fraction of 50% TP in composite, according to the experiments. The extreme tensile, flexural and impact strength of the TP bio-filler reinforced polymer composite was reported at the weight fraction of 40% TP in epoxy, and the attained values were 15 MPa, 20 MPa and 25 MPa, respectively.

Bio waste (Pistacia vera nut shell) filled polymer composites for tribological applications

The environmental concerns and quest for a sustainable future have encouraged the utilisation of bio-waste in a productive manner. In the present investigation, characterization studies such EDS, XRD and FTIR of pistacia vera (pistachio) nut shell particulates were carried out to have a knowledge of the morphological properties. Further, an attempt was made to utilise the bio-waste i.e. pistacia vera nut shell as a reinforcing phase in epoxy based polymer composites to assess the tribological behaviour of the fabricated composites. The pistachio shell particulate was incorporated with epoxy resin in different weight fractions (0, 10, 20 and 30%) to develop a new class of composite. The effect of filler content, normal load, sliding velocity and sliding distance on the two body abrasive wear behaviour of pistachio shell particulate reinforced epoxy composites was studied. The obtained results showed significant enhancement of abrasion resistance of the fabricated composites as compared to neat epoxy. Further, it was found that the composites with 20 weight percent of filler provide optimum abrasion resistance to the developed composite. The worn out surfaces of the composites were analysed using Scanning Electron Microscope to determine various failure mechanisms leading to deformation of the composite surface.

Tribological Properties of Fly Ash Blended Polymer Composites

In this study, it was studied that the abrasion resistance and characteristics of polymer composites with fly ash (FA). The epoxy based polymer composites are produced with resin and FA as mineral additive. Mixtures of different ratio by replacing the FA were added to the resin from 0 to 30% by weight. Polymeric samples were cured in air conditioning and they were taken from the molds after 24 hours. Polymeric samples gain ultimate strength after 7 days. Therefore, abrasion tests were performed on 7 aged specimens. Abrasion characteristics of polymer composites were defined by pin-on-disc test for 500 m under a dry friction condition and room temperature. Three types of loading conditions were carried out as 5, 10, 15 and 30 N. The hardness and wear resistance values increased with the increase in the content of fly ash. Showing the relationship between wear rate and hardness, an equation with parameters dependent on load was provided. There was an increase in the friction coefficient with an increase in the surface roughness values. In addition, dynamic friction was as a function of the wear rate. The wear surfaces of the polymer composites were analyzed using scanning electron microscopy. It was observed that the wear rate of the polymer composites and pure epoxy samples ranged from 17.82 to 172.96 mm3/Nm.

Effect of castor oil on mechanical and thermal behaviours of hybrid fibres reinforced epoxy based polymer composites

A series of cotton-nylon (CN) hybrid fibre polymer composites with varying castor oil as a crosslinker were prepared conventional wet hand-layup technique followed by vacuum bagging using an anhydride-based curing agent. The prepared composites have been assessed for mechanical and thermal behaviours. The Tensile strength, tensile modulus, percentage elongation at break, impact and flexural strength of these composites are evaluated are as per ASTM methods. The thermal attributes of the composites have been analysed by utilizing DMA. Results revealed that composites exhibited promising results with increase in fibre content. In addition, the composites prepared with castor oil also exhibited better results compared to the composites prepared without castor oil. The tensile Strength of the composite with 15 wt% of CN fibres in the presence of castor oil was found to be 35.98 N/mm2 and 38.32 N/mm2. Thermal behaviours of oil based composites were investigated by dynamic mechanical analyser (DMA). The glass transition (Tg) temperature and storage modulus of castor oil based composites shown higher results than composites prepared without castor oil.

Fabrication and Comparative Study on the Mechanical Properties of Epoxy based Polymer Composites with Coconut Shell Powder and Rice Husk Powder as Filler Materials

Fabrication and Comparative Study on the Mechanical Properties of Epoxy based Polymer Composites with Coconut Shell Powder and Rice Husk Powder as Filler Materials - written by D Soumyalata , Adarsh B , Ajas Latheef published on 2020/07/08 download full article with reference data and citations

Epoksi esaslı polimer kompozitlerde mikrodalga kürleme işlemi parametreleri

Microwave rapid curing processing has great potential for improving composite manufacturing such as reduction of curing time, energy requirements and operational costs. In this study, pre-waiting time and curing time effects on epoxy based polymer composites with and without fillers were investigated during a microwave curing process. Silica sand was used as filler material. After prefabrication of polymer samples with and without fillers, the samples were left waiting for pre-curing for 0, 30, 60 and 90 min. In addition, the power of microwave curing was altered to be either 100W, 300W, 450W, 600W or 800W. Other polymer samples were cured at the laboratory for 7 days for comparison. Tensile strength, energy to break, hardness, water absorption and microstructure investigations were performed on all samples. Results show that subjecting polymer materials to microwave treatment instead of keeping them at room temperature for 7 days yielded similar or higher tensile strength, hardness and impact toughness values in a shorter time.

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.

Influence of woven bast-leaf hybrid fiber on the physico-mechanical and sliding wear performance of epoxy based polymer composites

Epoxy composites reinforced with novel bast (Bauhinia vahlii) fiber and leaf (sisal) fiber combinations are designed, fabricated and characterized for physico-mechanical and sliding wear properties. The densities, void contents and the water absorption of these developed composites remain between the range of 1.247–1.254, 0.24%–0.48% and 0.147%–0.230%, respectively. The mechanical (impact energy, tensile strength, hardness and flexural strength) properties were found to increase with fiber reinforcement and remains highest for 6 wt% hybrid fiber content. The sliding wear tests were carried out as per Taguchi experimental design and L16 orthogonal array was utilized to study the impact of various combinations of control factors on wear rate. Analysis of variance investigation was conducted to determine the significance of each control factor on wear rate. The experimental outcomes demonstrated that fiber content is the most significant factor influencing the wear rate followed by sliding distance, normal load and sliding velocity. To study the possible wear mechanism, the worn surfaces of the composites were examined using scanning electron microscopy.

Effect of fiber length on mechanical behavior of coir fiber reinforced epoxy composites

Fiber reinforced polymer composites have played a dominant role for a long time in a variety of applications for their high specific strength and modulus. The fiber which serves as a reinforcement in reinforced plastics may be synthetic or natural. To this end, an investigation has been carried out to make use of coir, a natural fiber abundantly available in India. Natural fibers are not only strong and lightweight but also relatively very cheap. The present work describes the development and characterization of a new set of natural fiber based polymer composites consisting of coconut coir as reinforcement and epoxy resin as matrix material. The developed composites are characterized with respect to their mechanical characteristics. Experiments are carried out to study the effect of fiber length on mechanical behavior of these epoxy based polymer composites. Finally, the scanning electron microscope (SEM) of fractured surfaces has been done to study their surface morphology.

Mechanical and Thermal Properties of Polymer Composites for Electronic Packaging Application

Alumina (AE) and mica (ME) particles were used as fillers in epoxy-based polymer composites. Comparisons were made between the composites with respect to mechanical, thermal, and morphological properties. Mechanical and thermal studies were performed on the composites at various filler contents. Dispersion of the filler was evaluated using scanning electron micrograph (SEM). It was found that the flexural modulus of the composites was almost identical as far as AE and ME are concerned, particularly at 025 vol% of filler content. However, obvious increment was observed in the case of AE for flexural strength.