Izod Impact Research Articles

Sustainable hybrid composites reinforced with textile waste for construction and building applications

The textile waste fibre reinforced composites are environment-friendly and economically beneficial. However, textile waste reinforced composites have not gained the attention of composite manufacturers due to limited reported studies, a variation in the waste fibre’s physical and mechanical properties that affect the resulting composite properties. In this research, new types of hybrid composites reinforced with a carded web of cotton fibres extracted from waste cotton textiles were developed by laminating with unidirectional glass fibre preform and needle punched jute nonwoven fabric. The hybrid composite reinforced with 30 wt% of glass UD preform (on the total fibre weight in the composite) shows an improvement of tensile, flexural, and izod impact strength by ~ 266, ~300, and ~ 830%, respectively, compared to cotton web reinforced composites. The hybrid composite reinforced with 14 wt% of jute nonwoven (on the total fibre weight in the composite) shows an improvement of tensile, flexural strength, and izod impact by ~ 28, ~21, and ~ 99%, respectively, compared to cotton web reinforced composites. The developed composites are thermally stable enough. The developed composites can replace low and medium-cost timber in furniture items, construction, and building materials.

Electromagnetic shielding behavior of epoxy multi‐hybrid composites comprises of E‐glass fiber, Ag nanoparticle, and Ni nanosheet: A novel approach

AbstractHigh performance epoxy based EMI shielding hybrid composites were prepared and characterized for their mechanical, magnetic, and Electromagnetic Interference (EMI) shielding behavior. The aim of this research was to enhance the electromagnetic interference shielding effect of a nanocomposite at high frequency with good mechanical strength. The shielding effectiveness of the epoxy composite was improved via the addition of E‐glass/silver nanoparticle and nickel nanosheets. The reinforcements were silane surface modified to enhance the adhesion and dispersion of reinforcements with matrix. The composites were prepared via hand layup process using glass fiber, silver nanoparticle, and Ni nanosheets followed by room temperature curing. The characterization of hybrid composites was done in accordance with ASTM standards. The results revealed that the Ag and Ni along with E‐glass fiber improved conductivity, permittivity, and permeability of epoxy composite. Similarly, the mechanical behavior of nanocomposite was found to be increased for tensile, flexural, and Izod impact toughness. Moreover, a maximum wave attenuation of –48 dB was observed for 3‐mm thick composite shielding material in “J” band frequency. These mechanically sound high EMI shielding lightweight polymer composites could be used as potential material for aerospace, defense, tele‐communication, and satellite data transfer applications. Besides the reduction of EMI effect between electronic gadgets could improves the utility and life span of electromagnetic devices and gadgets in several engineering applications.

Effects of Maleic Anhydride Grafted Polypropylene on the Physical, Mechanical and Flammability Properties of Wood-flour/Polypropylene/Ammonium Polyphosphate Composites

In this study, maleic anhydride grafted polypropylene (MAPP) was incorporated as coupling agent in the wood-flour/polypropylene/ammonium polyphosphate composites (flame-retardant WPCs). The effects of MAPP content (5 wt.%, 10 wt.% and 15 wt.%) on the physical, mechanical and flammability properties of flame-retardant WPCs were investigated. The water soaking tests showed that the incorporation of MAPP could reduce the hygroscopicity of flame-retardant WPCs. The mechanical properties of WPCs were evaluated by three-point bending tests, unnotched Izod impact strength tests, and dynamic mechanical analysis. The results showed that the flame-retardant WPC containing 10 wt.% MAPP (WPC/APP/MAPP-10 %) performed the best flexural properties, the highest impact strength, E′ value, and tan δ at room temperature. The limiting oxygen index (LOI) tests and cone calorimetry tests showed that the incorporation of 10 wt.% MAPP endowed the flame-retardant WPC with the highest LOI value, the lowest peak-heat release rate, total heat release, CO/CO2 weight ratio and total smoke release. Moreover, the characterization of the WPCs combustion residues performed that WPC/APP/MAPP-10 % had the most complete carbonaceous structure with the highest graphitization degree after combustion. In general, the addition of 10 wt.% MAPP could impart the flame-retardant WPC with the optimum physical-mechanical properties and flame-retardant performance.

Introduction to the Study of Mechanical Properties of Terpolymer PP/EPDM Mixtures

Thermoplastic elastomers (TPEs), based in PP (Polypropylene) / EPDM (Ethylene Propylene Diene Monomer) have as purpose improving PP resistance and impact, aiming to a more comprehensive use in automotive market, among edifications, construction and packaging sectors, due to their recyclability properties. PP is a commodity, with a high melting point, high mechanical resistance and low density, posing a balance between physical and mechanical properties; in addition, it shows an easy processing, at low cost. In order to minimize this deficiency, EPDM, an impact modifier, can be used. Nevertheless, most of polymeric blends are incompatible and immiscible, i.e., show a mutual and limited solubility and in most of cases, a high interfacial tension. However, there is a relatively low interfacial tension (force which acts on transformation of a continuous structure in a dispersion) between PP and EPDM (approximately 0.3 mN.m-1), reducing the rate of breakup and facilitating the build-up of a continuous structure. This work aims to the study of compatibility of PP and EPDM blends and variation of mechanical properties, emphasizing that many properties of thermoplastic elastomers can be processed according with conventional thermoplastics methods: herein, PP/EPDM blends, 90/10, 80/20, 70/30 and 50/50 were characterized according to: Mechanical essays, Differential Scanning Calorimetry, Thermogravimetric Analyses, Melt Flow Index, Izod Impact Strength and Dynamic mechanical Analyses.

Mechanical Properties of Bamboo on Virgin and Recycled High-Density Polyethylene Matrix

Natural fiber-reinforced polymer composites are considered to have advantages over synthetic fibers, namely that they are more environmentally friendly but with better mechanical properties. The purpose of this study was to make a pure / recycled HDPE (High-Density Polyethylene) composite with bamboo fiber reinforcement by analyzing the mechanical properties of the composite. The method used in this research is experimental with a quantitative approach. Experiments are carried out by creating or manipulating certain conditions and by providing control over the test specimen. Pure / recycled HDPE plastics and bamboo fibers will be mixed in a machine extrusion molding with a temperature heater (160, 165, 170, 175) ° C. Before fabrication, bamboo fibers are treated with alkaline treatment, namely by immersing 5% NaOH. The ratio of mass fraction between vHDPE/rHDPE and bamboo fiber was 70%: 30%. This study evaluated the mechanical properties of HDPE-bamboo composites using Izod Impact testing with ASTM D 256-05 standards. Tests were carried out to analyze the differences between pure HDPE and recycled HDPE matrices on bamboo fiber reinforced composites. The mechanical test results showed that the impact strength on bamboo composites with recycled HDPE matrix was 2.69 (KJ / m2) while bamboo composites with pure HDPE matrices had an impact strength of 1.6 (KJ / m2). Thus, the mechanical properties measured by impact strength on composites with recycled HDPE matrices were better than composites with pure HDPE matrices. In accordance with the results of research that has been done, recycled HDPE can be used as a matrix composite with mechanical properties that are not too different from composites with pure HDPE matrices. This can be done as a means of utilizing recycled HDPE waste instead of pure HDPE.

Mechanical, thermal and ballistic performance of epoxy composites reinforced with Cannabis sativa hemp fabric

Among the natural fibers, the hemp fiber extracted from the stem of Cannabis sativa is, after sisal, the second most applied as reinforcement of polymer composites and increasingly used from automotive to civil construction industries. Polypropylene (PP) is the most common hemp fiber-reinforced matrix. Despite numerous papers on the application of natural fibers reinforcing polymer composites for ballistic protection, only one was so far dedicated to hemp fibers/PP with this purpose. In the present work, the main objective is for the first time to investigate the ballistic performance of the epoxy matrix reinforced with up to 30 vol% of hemp fabric. Epoxy is recently emerging as another strong alternative for the hemp fiber/fabric matrix. Due to the great variability in properties, a preliminary investigation was conducted on the basic mechanical and thermal behavior of the composites. The 30 vol% reinforcement with hemp fabric increased by 7.5 times the Izod impact energy as well as by more than 60% the tensile strength and 80% of the elastic modulus as compared to the neat epoxy. For all composites, a decrease of 20% in thermal temperatures (Tonset and Tmax) occurred in comparison to neat epoxy. The absorbed ballistic energy from the impact of 0.22 ammunition was significantly higher (95–108.5 J) than that previously reported of 36 J for hemp fabric/PP composite and others natural fiber/epoxy composites.

Melt extruded versus extrusion compression molded glass-polypropylene long fiber thermoplastic composites

Long fiber thermoplastic (LFT) composites are processed either with extrusion compression or fiber injection processes. The properties of LFT materials are highly influenced by processing techniques, which lead to different porosity contents, fiber length distributions, and fiber orientation distributions. It is important to understand the various LFT processing techniques and their effects on mechanical, thermal, and microscopic properties. This work considered LFT sheets processed via extrusion, which offers highly aligned fibers (referred to as “Tecnogor composites”), and LFT composites produced via extrusion compression molding (ECM), which offers a random distribution of fibers. Tecnogor composites exhibited higher flexural strength (35–65%), flexural modulus (132–172%), tensile strength (39–52%), tensile modulus (67–75%), and Izod impact resistance (195–220%) than the random LFT composites. This response was attributed to the aligned fibers in Tecnogor composites. Mathematical models including Halpin-Tsai and Lavengood-Goettler were used to predict and compare the Young’s modulus of Tecnogor and ECM composites, respectively.

Experimental and statistical analysis of robotic 3D printing process parameters for continuous fiber reinforced composites

3D printing technology has gradually taken its place in many sectors. However, expected performance cannot be obtained from the structural parts with this method due to the raw material properties and constraints of Cartesian motion systems. This technology cannot replace structural parts produced by traditional manufacturing methods. In order to avoid these constraints, it is preferred to use continuous fiber reinforced polymer composites in many areas such as automotive and aerospace industries due to their low weight and high specific strength properties. These automated composite manufacturing methods currently have limited production of geometric shapes due to the need for additional molds and production as flat surfaces. To overcome all these constraints, fiberglass reinforced ultraviolet ray-curing polymer matrix composite material are selected for robotic 3 D printing process and various parameters are examined. Fiber-polymer combination and layer structure formation was examined. Scanning Electron Microscopy (SEM) images of sections of 3 D printed test samples were taken and fiber resin curing was examined. The nozzle diameter, printing speed, fiber density and Ultra Violet (UV) light intensity parameters, which will provide effective 3 D printing process, are optimized with the Taguchi method. Tensile strength, flexural strength and izod impact values are considered as result parameters for optimization. It was found that it would be appropriate for 3D printing with a 1.0 mm nozzle diameter, 600 tex fiber density, 4 UV light, 600 mm/min printing speed. With these 3D printing process parameters, approximately 125 MPa tensile strength and 450 MPa flexural strength can be obtained. With this study, support and contribution was provided to researchers, composite producers, tool manufacturer and literature who want to use and develop this 3D printing process.

Interfacial improvements in cellulose nanofibers reinforced polylactide bionanocomposites prepared by in situ reactive extrusion

Grafting of polylactide (PLA) onto the cellulose nanofiber (CNF) (CNF‐g‐PLA) was prepared by in situ reactive extrusion using dicumyl peroxide (DCP) as a free radical initiator to improve the interfacial adhesion between CNFs and PLA. The effect of DCP content on the dynamic rheological properties, crystallization behavior, mechanical properties, and micromorphology of PLA/CNF (95/5) bionanocomposite was systematically investigated. FTIR spectra confirmed that PLA chains were successfully grafted onto the CNF surface by forming CC bonds. The presence of such CC crosslinks improved stress transfer at the CNF–PLA interface; SEM and TEM observations and adhesion factor calculated from DMA data confirmed that the synthesized graft copolymers improved the interfacial interaction between CNFs and PLA matrix, thus enhancing the mechanical properties of CNF‐g‐PLA nanocomposites. Compared with PLA/CNF (95/5) bionanocomposite, the maximum tensile modulus, tensile strength, elongation at break, and V‐notched Izod impact strength of CNF‐g‐PLA nanocomposites were increased by 31.8%, 20.0%, 12.0%, and 27.9%, respectively. WAXD and DSC analyses indicated that the crystallinity degree of the grafted CNF‐g‐PLA was higher than that of PLA/CNF (95/5) bionanocomposite, and first increased and then decreased with increasing DCP content. The polarized optical micrographs confirmed that DCP‐initiated grafting significantly increased the nucleation density but decreased the spherulite size of PLA. The melt strength of CNF‐g‐PLA nanocomposites was improved due to stronger intermolecular interaction by grafting. This one‐step in situ reactive extrusion technology provides an efficient and economical way to enhance the properties of PLA/CNF bionanocomposites.

Thermal analysis and polarized light microscopy as methods to study the increasing of the durability of PLA designed for 3D printing

The aim of the article was to study the possibility to use a sulfonic ester derivative of isophthalic acid as nucleating agent for increasing the durability of poly (lactic acid) designed for 3 D printing. The neat and nucleated PLA achieved via melt compounding were characterized through differential scanning calorimetry, polarized optical microscopy and by measuring its functional properties as Izod impact resistance and heat deflection temperature. The ability of nucleated PLA to be shaped as filaments and the potential of the obtained filaments to be 3 D printed as well were studied. The nucleation with a sulfonic ester derivative of isophthalic acid changes the polymer morphology and therefore generates the improvement of PLA functional properties and its durability. The obtained nucleated PLA is able to be shaped as filaments, which prove to have better 3 D printability because it melts and crystallizes in narrow temperature ranges, crystallizes with high speed, at higher temperature and the 3 D printed items can be quickly removed from the printing support.

The use of recycled low‐density polyethylene films from protective prepreg for the development of nanocomposites with bentonite clay

AbstractPrepreg is a pre‐impregnated composite fiber where a thermoset polymer matrix material is present. Before being used, these materials are kept at low temperatures and have a low‐density polyethylene (LDPE) film for your protection. The increase in the use of structural composites based on prepregs causes an increase in the amount of protective LDPE film. This material is usually discarded or incinerated and can cause great damage to the environment. Thus, the present work aimed to study the feasibility of recycling up to 100% of protective LDPE (rLDPE) to develop blends‐based nanocomposites with rLDPE/virgin LDPE (60/40, 70/30, 80/20, 90/10 and 100/0) with the addition of 5 wt% of compatibilizer agent (maleic anhydride grafted LDPE, LDPE‐g‐MA), and 1 wt% of bentonite (BNT) using a co‐rotational twin‐screw extruder, followed by hot pressing in a hydropneumatic press and die‐cutting. Water absorption test, thermal aging resistance, morphological characterization by scanning electron microscopy, mechanical properties by Izod impact strength and tensile tests, and differential scanning calorimetry were performed. By the results, it was possible to verify the viability of 100% of the recycling of rLDPE. The results showed a good distribution of 1 wt% of BNT in the matrix, better mechanical properties when compared with virgin LDPE. Furthermore, the thermal properties, water absorption test, and thermal aging resistance showed no statistical differences between the samples. These results confirm the effectiveness and the environmental gain in the use of the recycled material.

Application of low-grade recyclate to enhance reactive toughening of poly(ethylene terephthalate)

This paper presents a new recognition in reactive toughening of poly(ethylene terephthalate) (PET), namely the major effect of the molecular weight of PET on the evolution of the compatibilization and crosslinking reactions with ethylene‑butyl acrylate-glycidyl methacrylate (EBA-GMA) type reactive terpolymer, and thus indirectly on its toughening efficiency. It was found that the use of highly degraded recycled PET (rPET) grades, due to the available larger number of reactive functional end groups and increased mobility of the decreased-molecular-weight chains, multiplies the impact strength of the product compared to that of original PET (oPET) with identical EBA-GMA contents. The evinced noticeable difference between the toughening behaviour of rPET and oPET is explained by morphological and interfacial factors and connected to differences in rheological behaviour as well. The reactive oligomeric rPET macromolecules form a Toughening Enhancer Interphase (TEI) around the dispersed particles. Based on systematic analyses, conclusions were drawn regarding the quality, i.e. optimal intrinsic viscosity (IV) range, and quantity of rPET to be used to obtain high-impact-strength PET blends (notched Izod impact strength higher than 40 kJ/m2) with optimised mechanical properties, being suitable even for injection moulding applications, at significantly lower terpolymer contents (10.0–12.5 wt%) than expected. Besides, the proposed new way of utilisation of PET recyclates, especially the unmarketable highly degraded fractions, is believed to give a new driving force in PET recycling.

Effect of retrogression and re-aging on mechanical &wear properties of LM-25 aluminium alloy

.The effect of retrogression and re-aging on the mechanical and wear properties of LM 25 were studied. The raw material ingot was casted in to cylindrical rods. The samples were solutionized at 530 °C for 2 hours and then artificially aged at 165 °C for 12 hours. The samples were heat treated using retrogression process at temperatures 200 °C, 225 °C, 250 °C, and 275 °C and re-aged at 165 °C for 12 h. The samples were tested for its hardness and tensile strength and found that the 200°C retrogressed and re-aged sample (HT1) was having high hardness (125 HV) and the tensile strength was recorded as highest (182 N/mm2) when compared to other samples. Izod impact test was conducted for all the samples and it remains same for all the samples. Dry sliding wear test results shows that HT1 sample was having least wear rate when compared to other samples.Microstructure of HT1 sample reveals that the silicon precipitates of sleek and finer grain structure, which improves the hardness and tensile strength.

Biomimetic construction peanut-leaf structure on ammonium polyphosphate surface: Improving its compatibility with poly(lactic acid) and flame-retardant efficiency simultaneously

To suppress the fire hazards caused by polymer materials and at the same time keep or improve the properties of polymer materials, the exploration of high-efficiency flame retardants with property enhancement function is quite urgent. Inspired by the high adhesion result from the hierarchical micro-nanostructures of peanut leaves, herein, a bionic peanut-leaf structure is constructed on the surface of widely used flame retardant, ammonium polyphosphate (APP) to improve the compatibility with polymers. To test the validity of this modification method, poly(lactic acid) (PLA) with poor toughness and high fire risk is selected as a model polymer and blended with modified APP (MAPP). The high interfacial adhesion caused by the hierarchical micro-nanostructures of MAPP enhance the compatibility with PLA resulting in the toughness enhancement of materials. Owing to unique microstructure, 5 wt% addition of MAPP not only endow material with good flame retardancy but also enhance the elongation at break and notched Izod impact strength to 21 and 3 times of pure PLA. The biomimetic strategy outlined here can be extended to other flame retardant and may provide us a new method to balance the flame retardancy and mechanical properties.

Effect of carbon nanotubes functionalization on properties of their nanocomposites with polycarbonate/poly(acrylonitrile‐butadiene‐styrene) matrix

AbstractIn this work, a comparative study evaluating the influence of different functionalization of carbon nanotubes on the properties of nanocomposites with polymeric matrix was performed. A 50/50 wt% polycarbonate (PC)/poly(acrylonitrile‐butadiene‐styrene) (ABS) blend was used as polymeric matrix of the nanocomposites. The comparison was made between nanocomposites reinforced with covalently functionalized multiwall carbon nanotubes (MWCNTf) and MWCNTf/nanoclay hybrid functionalization. The effect on the mechanical and morphological properties of the nanocomposites was evaluated through tensile and Izod impact tests and scanning electron microscopy and transmission electron microscopy (TEM) analyses. The thermal characterization of PC/ABS blends and nanocomposites was performed by differential scanning calorimetry (DSC). Results showed that both methods of functionalization of MWCNTs increased the stiffness and impact resistance of the nanocomposites. TEM micrographs indicated the preferred location of the reinforcements in the SAN phase of ABS. Results from DSC indicated an increase in the thermal resistance of the nanocomposites.

Eco‐friendly bamboo fiber‐reinforced poly(butylene succinate) biocomposites

AbstractThis research experimentally synthesizes bamboo fiber‐reinforced biocomposites by using bamboo fiber (BF) as filler material and poly(butylene succinate) (PBS) as biodegradable polymer matrix. The experimental filler materials included alkaline‐treated BF and untreated BF. The alkali treatment of BF was carried out to remove the hydrophobic components from the BF surface. The PBS/BF ratios were varied between 90/10, 80/20, and 70/30 (w/w). The experiments revealed that the tensile strength of PBS/treated BF biocomposites were higher than that of PBS/untreated BF ones, independent of BF content. Elongation at break decreased with increase in BF content, while Young's modulus increased as BF content increased. The Izod impact strength of the biocomposites were similar to that of neat PBS. The water absorption capacity of PBS/BF biocomposites increased with increase in BF content. The water uptake of alkali‐treated BF was higher than that of untreated BF as lignin and hemicellulose were removed from the BF surface. The novelty of this research lies in the use of biodegradable PBS polymer as biocomposite matrix reinforced with natural fiber, as opposed to conventional petroleum‐based non‐biodegradable polymers. Moreover, this research also performed water absorption experiments to characterize the effect of alkali treatment on bamboo fibers. The characteristic of biocomposites is appropriate to be used as packaging and indoor furniture parts.

Influence of stacking sequence on impact strength/hardness of CF/GF hybrid composites fabricated by VARIMC technique

For light weight and high strength applications, different types of fibers such as carbon fiber (CF), glass fiber (GF) and Kevlar fibers are stacked layer by layer to fabricate low density laminates. This process is known as hybridization and fabricated composites are called hybrid composites. These types of composites used in high structural applications. Hybrid composites are known for their high strength to weight ration and ability to absorb energy. In present work, Izod impact and shore-D hardness response of hybrid composites (GF and CF reinforced polymer matrix) were investigated. Hybrid composites with different stacking sequence of CF and GF were fabricated by vacuum assisted resin infusion microwave curing (VARIMC) process. Bidirectional woven fabrics of CF and GF was used. Three types of stacking sequence (CGCGCGC)3, (C2G3C2)3 and (GC2GC2G)3 was used for hybrid composites. According to ASTM standard for testing, the thickness of the laminates was maintained about 6 mm. Results revealed that the variation of impact strength was strongly depends on lay-up stacking sequence of GFs and CFs in hybrid composite laminates. Three modes of failure of laminates i.e., matrix cracking, fiber breakage and delamination were observed.

Estimation of IZOD impact strength between different concentrations of chitosan-reinforced denture base resins.

Poly-methyl methacrylate (PMMA) is an universally acceptable denture base material. Efforts are made to increase the applications with the addition of new constituents. Chitosan has established antifungal properties. The mechanical properties of Chitosan-denture base composite is less evaluated in the literature. This study estimates the differences in impact strength of material for different concentrations of chitosan-reinforced denture base resins. The study estimated the differences in IZOD impact strength of denture base resin reinforced with 0%, 5%, 10% and 15% of chitosan by weight. The acrylic samples were fabricated in according to ISO 180 regulations. The study had four test groups (n = 10). ACh0 was the control group with no reinforcements. ACh5, ACh10 and ACh15 had chitosan reinforcement of 5%, 10% and 15% by weight. The samples were processed by conventional heat polymerization cycle and tested in IZOD impact testing machine. The data were recorded and statistically analyzed with Kruskal-Wallis test. The mean impact strength was high in ACh5 (4.25 ± 1.05 kJ/m2) compared to ACh0 (2.88 ± 0.60 kJ/m2), ACh10 (3.63 ± 0.40 kJ/m2), ACh15 (3.38±0.60 KJ/m2). Statistically significant differences between the test groups was determined by Kruskal-Wallis and post hoc Bonferroni test (Chi-square = 12.843, P = .005, df = 3). The impact strength of denture base resin increased with 5% chitosan compared with other percentage of chitosan. No statistical significant relationship was observed between the groups.

Influence of Fiber Orientation on Impact Resistance Behavior of Woven Sisal Fiber Reinforced Polyester Composite

Woven natural fiber reinforced polymer composites have better tensile, flexural, and compressive strength compared to the mechanical properties of unidirectional and randomly oriented NFRPC because of the interlacing of fiber bundles. However, the characterization of impact behavior with different fiber orientation such as 30°/60°, 0/90°, 30°/−45°, and 45°/−45° woven sisal fiber reinforced polyester composite was not studied vigorously. Thus, this paper focuses on the experimental characterization of the impact resistance behavior on woven sisal fiber reinforced polyester composite materials for semistructural part by using Izod impact testing setup. The 30°/60°, 30°/−45°, 0°/90°, and 45°/−45° woven sisal fiber was prepared using nailed wooden frame as a warp and weft guider. The woven sisal fiber was impregnated in order to make woven sisal fiber dimensionally stable. Using 40% by weight of fiber and 60% by weight of polyester, the composite was developed using hand layup process. The morphology and cross‐sectional elemental detection was carried out using scanning electron microscope (SEM) assessment in leather development institute (LDI). Finally, impact tests were carried out using Izod impact testing setup in Addis Ababa Science and Technology University (ASTU). The average impact strength of a 40 wt% fiber 45°/−45° woven sisal fiber reinforced unsaturated polyester composite (WSFRPC) test specimen with consecutive warp and weft tow spacing of 2 mm was 342.67 J/m and this was greater energy compared to the other orientations. But the average impact strength of a 40 wt% fiber 30°/60° WSFRPC of test specimen with consecutive warp and weft tow spacing of 2 mm was 241.33 J/m.

Properties of Oil Shale Ash Filled Polypropylene Composite Material: Mechanical and Physical Characterization

The outcome of oil shale ash (OSA) filler addition on the mechanical, morphological, thermal and water uptake properties of the polypropylene (PP) matrix was investigated. The test specimens were prepared with various ratios of the mixtures that contain OSA and polypropylene in the following weight percentages: 0%, 10%, 20%, 30% and 40% OSA in polymer matrix. Composites specimens were produced by using a co-rotating twin screw extruder and a thermal press machine. The properties of the polymer composite specimens were characterized by using a universal testing machine (WDW-5) and izod impact testing machine (FI-68). The morphology of the composite samples was also characterized by using the scanning electron microscopy (SEM). Impact strength and Young’s modulus of the OSA/PP composite formulations were consistently improved on OSA inclusion. On the other hand, addition of OSA to pure polypropylene had consistently reduced the tensile stress at yield, tensile stress at rupture, tensile strain at yield and tensile strain at break. Adding OSA to polypropylene decreased the maximum flexural stress and flexural strain of maximum force. The observed SEM confirmed that the addition of OSA to pure polypropylene resulted in a significant increase in its agglomerates and filler pullout. Differential scanning calorimetry (DSC) results confirmed the addition of the OSA to pure polypropylene resulted in a significant decrease in normalized heat of crystallization, normalized enthalpy of melting. Where the degree of the crystallinity (Xc) of polymer composite decreased from 59% to 34% for 0% and 40% OSA addition, respectively. While melting temperature (Tm) of the composite did not change (167 °C) the crystallization temperature (Tc) increased from 116.6 °C to 127.1 ºC for 0% to 40% OSA addition, respectively. Water uptake, however, demonstrated different behaviour. The initial addition of OSA to polypropylene increased the water uptake property up to 4% for the 40% filler addition. The results of this study demonstrated that the OSA could be used as reinforcement material for polypropylene, as long as good mechanical properties and homogeneous morphology obtained.