Izod Impact Energy Research Articles

Extrusion and characterization of recycled polyethylene terephthalate (rPET) filaments compounded with chain extender and impact modifiers for material-extrusion additive manufacturing

The continuous growth of annual production and consumption of polyethylene terephthalate (PET) is coined with increasing waste that leaks into the environment, landfills and oceans as microplastics and nano plastics fragments. Upcycling the recycled PET to make a feedstock for the fast-growing material-extrusion additive manufacturing (MEX-AM) technology can contribute to the solution and supports the concept of sustainable materials. In this work, extrudable filaments comprising recycled polyethylene terephthalate (rPET) with low-cost additives, such as pyromellitic dianhydride (PMDA) as a chain extender, styrene-ethylene-butylene-styrene terpolymer functionalized with maleic anhydride (SEBS-g-MA), a thermal modifier and toughening agent, ethylene-ethyl acrylate-glycidyl methacrylate terpolymer (E-EA-GMA), a functional reactive elastomeric impact modifier and ethylene-ethyl-acrylate (EEA), a non-reactive elastomeric impact modifier, have been fabricated using the twin-screw extruder. The optimum extrusion process parameters for producing uniform filaments of different rPET compounded formulations have been identified, this includes the extrusion die temperature of 280 °C and the screw speed of 150 ± 3 rpm. The compounded filaments are then printed into standard ASTM test specimens for thermal characterization and mechanical characterization, including glass transition and melting temperatures, crystallinity and crystallization temperature, tensile strength, tensile modulus, ductility, flexural strength, and Izod impact energy. Furthermore, the melt flow index for the filaments was measured. More significantly, the experimental data showed that compounding rPET with such additives in the reactive twin-screw extrusion process results in uniform filaments that display advantageous thermal and mechanical properties and can be used as a feedstock in the MEX-AM technology. This study suggests that compounding the recycled PET pellets with low-cost additives while extruding them into filaments for MEX-AM offers excellent potential to make high-value-added customized products from a sustainable polymer feedstock, such as prototyping, tooling, testing components or end-use internal components for small machines and cars.

Influence of hybrid nano/micro particles on the mechanical performance of cross-ply carbon fibre fabric reinforced epoxy polymer composite materials

This study presents the flexural strength, compressive strength, and impact energy behaviour of graphene nanoplates and fly ash microparticle-loaded cement-based CFRP composites manufactured by the vacuum-assisted resin infusion method (VARIM). The composite structures consist of a fixed ratio of graphene nanoplates (2%), fly ash (2%), silica (2%), cement (2%), and sand (4%) particles filled into cross-plied carbon fibre-reinforced epoxy resin polymer composite beams and columns. Composites fabricated by hand lay-up methods because of infiltration problems. A three-point bending test through the width was used to measure the flexural strength of the graphene nanoplate (GnP)-filled CFRP composite beam. The low-velocity Izod impact and Charpy impact tests through the thickness were used to determine Charpy impact energy (3.46 J), Izod impact energy (2.5 J), and the dynamic fracture toughness of notch specimens under Charpy (28.5 KJ/m2) and Izod impact (25.0 KJ/m2). Also, the compressive test method was used to measure the compressive strength of hybrid particles and short glass fibre-reinforced epoxy resin composite square and circular columns. The results show compressive strength and flexural strength. Izod impact energy, Charpy impact energy, and dynamic fracture toughness of hybrid nano/microparticle-filled fibre composites have higher values than virgin fibre composites because of the influence of graphene nanoparticles and the perfect interface bonding between two dissimilar molecules of nano and microparticles, which improve the fracture toughness and absorb impact energy. Overall, the results show that molecules of nano/microparticle-filled carbon fibre and glass fibre-reinforced epoxy resin composites can be used in seismic wave resistance because of their improved mechanical properties compared to virgin fibre composites. In addition, SEM micrographs clearly show that nano- and microparticles are resistant to crack propagation and the debonding of matrix fibres.

Mechanical Performance of Hybrid Graphene Nanoplates, Fly-Ash, Cement, Silica, and Sand Particles Filled Cross-Ply Carbon Fibre Woven Fabric Reinforced Epoxy Polymer Composites Beam and Column

The main goal of this study is to reduce the brittleness of a fibre-reinforced cement base structure when exposed to the effects of graphene nanoplates, fly ash, silica, sand, and cement fillers to better understand the effect of hybrid nano/micro particle fillers on the mechanical performance of cross-ply carbon fibre reinforced epoxy resin composites. A three-point bending test through the width was used to measure flexural strength. The impact tests Izod at low impact velocity and Charpy through the thickness were used to determine the dynamic fracture strengths of pre-cracked and non-cracked composite samples. Also, the compressive test method was used to measure the compressive strength of hybrid particles and short glass fibre-reinforced epoxy resin composite square and circular columns. The results show compressive strength and flexural strength. Izod impact energy, Charpy impact energy, and dynamic fracture toughness of hybrid nano/microparticle-filled fibre composites have higher values than virgin fibre composites due to the influence of graphene nanoparticles and perfect interface bonding between two dissimilar molecules of nano and microparticles, which improve the fracture toughness and absorb impact energy. Overall, the results indicate that molecules of nano/microparticle-filled carbon fibre and glass fibre-reinforced epoxy resin composites can be used in aggressive environments because of the improved mechanical properties in comparison to the virgin fibre composites. In addition, SEM micrographs clearly indicate that nano- and microparticles are resistant crack propagation and deboned of matrix fibres.

Dynamic Fracture Toughness Behaviour of CFRP-Foam-CFRP Sandwich Composite and Particles Filled Hybrid Glass Fiber Cloth, Graphene Nanoplates Coated Glass Fiber Strand Composite Materials under Low Impact Velocity

The main objective of the present study is to investigate the dynamic fracture toughness behaviors of CFRP-Foam-CFRP sandwich composite of V-notched through -thickness, surface, and un-notched specimens under Izod, and Charpy impact tests.  The sandwich composite structures are made of cross-plied carbon fiber reinforced plastic (CFRP) composite faces with polyurethane foam core. CFRP composites are used to combine the upper face and the lower face through the core in stitched sandwich structures. Compressive strength of weight drop impact perforated and un-perforated sandwich composite specimens are measured from a universal testing machine. Also, particles (Al2O3, CNTs, and cement) filled glass fiber cloth and graphene nanoplates coated glass fiber strands reinforced polymer hybrid composite are fabricated for V-notched, un-notched Izod impact and Charpy impact tests. The results show that weight drop impact energy is lower than the Izod impact energy but higher than the Charpy impact energy, whereas the dynamic fracture toughness of Izod impact energy is more than the Charpy and weight drop impact energy due to geometry of impactor and sandwich specimen. However energy and dynamic fracture toughness of Al2O3, CNTs, and Cement filled un-notched hybrid composites higher than the notched hybrid composites under Izod Impact. The dynamic fracture toughness and energy of CNTs filled hybrid composites is higher than the sandwich composites, Al2O3, and Cement filled hybrid composites under Charpy Impact.

Post‐consumer recycled high density polyethylene/polypropylene blend with improved overall performance through modification by impact polypropylene copolymer: morphology, properties and fracture resistance

AbstractThe effect of an impact polypropylene copolymer (IPC) having excellent stiffness–toughness balance on the microstructure and properties of a blend comprising 80 wt% recycled high density polyethylene (rHDPE) and 20 wt% recycled isotactic polypropylene (rPP) was studied. Morphological observations revealed improved interfacial interactions, a finer dispersion state and a more homogeneous phase morphology upon IPC incorporation into the blend up to 20 wt%. Flexural modulus, flexural strength, tensile strength and tensile ductility were steadily increased with IPC loading, and exhibited 13%, 14%, 35% and 520% improvement at 20 wt% IPC. A monotonic rise in Izod impact energy, accompanied by a transition from semi‐brittle to fully ductile failure mode, was observed with IPC concentration, so that this parameter showed 110% increment at 20 wt% IPC. The change in properties was attributed to the compatibilization, toughening as well as reinforcing effects of the IPC phase in the modified blends. Melting and crystallization of the blends were studied by the DSC technique. Failure mechanisms and micro‐deformations accompanying the impact fracture process of the blends were closely examined, and the role of IPC in improving the toughness and fracture resistance of the modified blends was clarified. The results were interpreted in terms of interfacial strength, efficiency of stress transfer across the phase boundaries, and stability of plastic micro‐deformations during the fracture process. The results clearly demonstrate that simultaneous improvement in stiffness, strength and (impact) toughness of the incompatible rHDPE/rPP blend can be achieved by modification with a properly chosen IPC. The present work addresses some challenges, with respect to stiffness and strength, encountered with the use of conventional elastomeric and/or plastomeric olefin copolymers as common modifiers for polyolefin blends. © 2021 Society of Industrial Chemistry.

Impact and Tensile Properties of Polyester Nanocomposites Reinforced with Conifer Fiber Cellulose Nanocrystal: A Previous Study Extension.

In a recent paper, novel polyester nanocomposites reinforced with up to 3 wt% of cellulose nanocrystals (CNCs) extracted from conifer fiber were characterized for their crystallinity index, water absorption, and flexural and thermal resistance. The use of this novel class of nanocomposites as a possible substitute for conventional glass fiber composites (fiberglass) was then suggested, especially for the 1 and 2 wt% CNC composites due to promising bending, density, and water absorption results. However, for effective engineering applications requiring impact and tensile performance, the corresponding properties need to be evaluated. Therefore, this extension of the previous work presents additional results on Izod and tensile tests of 1 and 2 wt% CNC-reinforced polyester composites, together with a comparative cost analysis with fiberglass. The chemical effect caused by incorporation of CNCs into polyester was also investigated by FTIR. In comparison to the neat polyester, the Izod impact energy increased 50% and 16% for the 1 and 2 wt% composites, respectively. On the other hand, the tensile strength and Young’s modulus remained constant within the ANOVA statistical analysis. FTIR analysis failed to reveal any chemical modification caused by up to 2 wt% CNC incorporation. The present impact and tensile results corroborate the promising substitution of a polyester composite reinforced with very low amount of CNCs for common fiberglass in engineering application.

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.

High-performance molded composites using additively manufactured preforms with controlled fiber and pore morphology

In this work, large-scale multimaterial preforms produced by additive manufacturing (AM) underwent compression molding (CM) to produce high-performance thermoplastic composites reinforced with short carbon fibers. AM and CM techniques were integrated to control the fiber orientation (microstructure) and to reduce void content for the improved mechanical performance of the composite. The new integrated manufacturing technique is termed “additive manufacturing-compression molding” (AM-CM). For the present study, the most common materials were used for large-scale printing, i.e., acrylonitrile butadiene styrene (ABS), carbon fiber (CF)–filled ABS (CF/ABS) and glass fiber (GF)–filled ABS (GF/ABS). Three different manufacturing processes; (a) AM (b) extrusion compression molding (ECM), and (c) AM-CM were used to prepare four different panel configurations: (1) neat ABS, (2) CF/ABS, (3) overmold (CF/ABS over neat ABS), and (4) sandwich (neat ABS between two CF/ABS layers). The mechanical properties (tensile and flexural strength and modulus, and Izod impact energy) of samples prepared via all three manufacturing processes were compared. X-ray microcomputer tomography was employed to evaluate the fiber orientation distribution and the volumetric porosity content. The preform maintained high fiber alignment (≈ 82% of fibers within the range of 0–20° in the deposition direction), and the volumetric porosity was reduced by 50% from 3.79% to 1.91% after compression. The alignment of long pores along the deposition direction was also observed. The mechanical properties are discussed with correlation to the fiber alignment and void content in the samples. CF/ABS samples prepared by AM-CM showed significant improvement of 11.15%, 35.27%, 28.6%, and 74.3% in the tensile strength, tensile modulus, flexural strength, and flexural modulus, respectively, when compared with samples prepared by ECM. Unique aspects of this study are the demonstration of large-scale multimaterial AM and the use of multimaterials as preforms to make high-performance composites.

Mechanical characterization of animal fibre-based composites

Horsehair-based composites have been prepared by reinforcing polylactic acid (PLA) using hot compression molding. The weight fraction of horsehair fibre in composites has been varied from 0% to 30 wt.% to investigate the effect of fibre loading on the mechanical properties and moisture absorption performance of the developed composites. The mechanical properties, such as strength and modulus (tensile and flexural), impact energy, and moisture absorption behaviour of the fabricated composites, are experimentally evaluated. The experimental results recommend that the composites reinforced with 20 wt.% horsehair exhibit superior mechanical properties as compared to other developed composites. The tensile strength and modulus, flexural strength and modulus, Charpy and Izod impact energy of the composites reinforced with 20 wt.% horsehair are improved by 9.52, 28.74, 7, 5.63, 398.11 and 379.31% as compared to, one-on-one, neat PLA. The findings also reveal that the percentage of moisture absorption of the developed composites increases with an increase in the fibre content in the developed composites.

Tucum Fiber from Amazon Astrocaryum vulgare Palm Tree: Novel Reinforcement for Polymer Composites.

The replacement of synthetic fibers by natural fibers has, in recent decades, been the subject of intense research, particularly as reinforcement of composites. In this work, the lesser known tucum fiber, extracted from the leaves of the Amazon Astrocaryum vulgare palm tree, is investigated as a possible novel reinforcement of epoxy composites. The tucum fiber was characterized by pullout test for interfacial adhesion with epoxy matrix. The fiber presented a critical length of 6.30 mm, with interfacial shear strength of 2.73 MPa. Composites prepared with different volume fractions of 20 and 40% tucum fiber were characterized by tensile and Izod impact tests, as well as by ballistic impact energy absorption using .22 ammunition. A cost analysis compared the tucum fiber epoxy composites with other natural and synthetic fiber reinforced epoxy composites. The results showed that 40 vol% tucum fiber epoxy composites increased the tensile strength by 104% and the absorbed Izod impact energy by 157% in comparison to the plain epoxy, while the ballistic performance of the 20 vol% tucum fiber composites increased 150%. These results confirmed for the first time a reinforcement effect of the tucum fiber to polymer composites. Moreover, these composites exhibit superior cost effectiveness, taking into account a comparison made with others epoxy polymer composites.

Promising Mechanical, Thermal, and Ballistic Properties of Novel Epoxy Composites Reinforced with Cyperus malaccensis Sedge Fiber

Composites reinforced with natural lignocellulosic fibers (NLFs) are gaining relevance as the worldwide demand for renewable and sustainable materials increases. To develop novel natural composites with satisfactory properties, less common NLFs should also be investigated. Among these, the Cyperus malaccensis (CM), a type of sedge fiber, is already used in simple items like ropes, furniture, and paper, but has not yet been investigated as composite reinforcement for possible engineering applications. Therefore, the present work evaluated for the first time the properties of novel epoxy composites incorporated with 10, 20, and 30 vol.% of CM sedge fibers. Tensile, Izod-impact, and ballistic impact tests were performed, as well as Fourier transform infrared (FT-IR) spectroscopy and thermal analysis of the composites. Results disclosed a decrease (−55%) in tensile strengths as compared to the neat epoxy. However, the elastic modulus of the 30 vol.% sedge fiber composite increased (+127%). The total strain and absorbed ballistic energy did not show significant variation. The Izod impact energy of the 30 vol.% composite was found to be 181% higher than the values obtained for the neat epoxy as a control sample. An increase in both stiffness and toughness characterized a reinforcement effect of the sedge fiber. The thermal analysis revealed a slight decrease (−15%) in the degradation temperature of the CM sedge fiber composites compared to the neat epoxy. The glass-transition temperatures were determined to be in the range of 67 to 81 °C.

Statistical analysis of notch toughness of epoxy matrix composites reinforced with fique fabric

Reinforcement of polymer matrices with natural lignocellulosic fibers (NLFs) is today presenting great potential for the reduction of both product weight and cost in many industrial sectors as well as the advantage of being renewable and eco-friendly materials. For some industrial applications, especially in ballistic armor, the materials are expected to meet technical and mechanical requirements in terms of impact behavior, which motivate the present work. This work conducted a notch toughness assessment by Izod and Charpy impact tests of epoxy matrix composites reinforced with different volume fractions of fique fabric, up to 50vol%. Statistical analyses indicated significant differences between composites with distinct amount of fique fabric. Failure mechanisms were analyzed by scanning electron microscopy (SEM). The results revealed that composite reinforced with 40vol% of fique fabric presented the best notch toughness performance. Composites with 15 and 30vol% of fique fabric display predominantly brittle fracture associated with lower impact energies. With higher amount, 50vol%, of fique fabric reinforcement both Izod and Charpy impact energy suffered a small decrease according to the Roger and Plumtree model.

Effect of weave parameters on the mechanical properties of 3D woven glass composites

Due to the complex structure of 3D woven fabrics, their mechanical properties and failure modes tend to deviate from that of conventional equivalent 2D woven and unidirectional fabric composites. A lack of in-depth understanding of the relationships between the weave parameters and mechanical properties of 3D woven composite materials has inspired this investigation. This paper presents a comprehensive experimental study of the effect of pick density on the mechanical properties such as tension, compression, short beam shear and Izod impact energy in 3D layer-to-layer glass/epoxy woven composite structures. The 3D woven fabrics are manufactured in two different pick density extremes: 4 and 14 picks/cm with a constant end density of 12 ends/cm from Hybon 2002 E glass fibres. The mechanical properties were improved by the decrease in waviness and misalignment of the load carrying fibres. An interesting observation which has never been seen before was made in lower pick density specimens under tensile loading. Severe diagonal crack propagation because of strain-induced shear failure was observed and attributed to influence of the movement of misaligned yarns with increasing tensile strain. This study has helped in deriving a relationship between the weave parameters and the in-plane mechanical properties and expected failure in this 3D woven layer-to-layer warp interlock glass fabric.

Izod impact energy study of re-forced polisher matrix compounds with curaous fibers aligned and epoxy matrix reinforced with piassava fibers

Polymer matrix composites have been applied in components such as helmets and shielding for which tough-ness is a major requirement. Natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. The objective of this work was then to assess the Izod impact resistance of polymeric composites reinforced with different amounts, up to 30% in volume, of a promising high strength natural fiber from the Amazon region known as curaua. Among these, the piassava fiber extracted from a palm tree native of South America stands as one of the most rigid with a potential to be used as composite reinforcement. Therefore, the present work investigates the notch toughness behavior, by Izod impact tests, of epoxy composites reinforced with up to 40 % in volume of continuous and aligned piassava fibers.The results showed a remarkable increase in the notch toughness with the amount of incorporated curaua fibers. This can be attributed to a preferential debonding of the fiber/matrix interface, which contributes to an elevated absorbed energy. . It was found that the incorporation of piassava fibers results in significant increase in the impact energy of the composite. Scanning electron microscopy analysis showed that the nature of the piassava fiber interface with the epoxy matrix is the major responsible for the superior toughness of the composite. Keywords:Piassava, curaua, polymer matrix, epoxy matriz, Izod

Engineering impact modification of anionically polymerized polyamide 6

ABSTRACTA new approach to toughen anionically polymerized polyamide 6 (aPA6) is presented using an additive monomer that simultaneously polymerizes and undergoes reaction‐induced phase separation (RIPS) during aPA6 polymerization. In this work, the selection of additive, concentration, and reaction conditions are controlled in such a way to produce rubbery domains of the proper size and interparticle distance necessary for effective toughening without the diminishment of other engineering properties. This method circumvents the issues of particle dispersion and mixture viscosity that are commonly associated with other conventional methods of impact modification thereby making it an ideal system for fiber‐reinforced aPA6 reaction injection molding. Controlled phase separation, modulus retention, and increased crystallinity are achieved at low additive concentrations. The additive monomer used in this case is octamethylcyclotetrasiloxane (D4). D4 undergoes RIPS during aPA6 polymerization and simultaneously polymerizes to produce polydimethylsiloxane. Optimal properties to maximize fracture energy without reducing the modulus are achieved with 2 wt % D4. The fracture mechanisms are investigated and results show approximately a 3‐fold increase in energy release rate and a twofold increase in Izod impact energy. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46823.

Mechanical Strength Behaviour of Silane Treated E-glass Fibre/Al 6061 & SS-304 Wire Mesh Reinforced Epoxy Resin Hybrid Composite

In this research work the mechanical strength behaviour of silane treated e-glass fibre, Aluminium 6061 and stainless steel 304 metal wire mesh reinforced epoxy resin hybrid composites were analyzed. The principal objective of this research work is to unveil the importance of silane treatment on metal surface in adhesion and delamination resistance in composites. The reinforcements were acid etched then silanated by 3-Aminopropyletrimethoxylane via aqueous solution method. The mechanical properties were found increase for surface modified reinforcements rather than as-received reinforcement epoxy composites. Maximum tensile strength, flexural strength and Izod impact energy of 134 MPa, 241 MPa and 5.4 J were observed for composite consist of surface modified SS-304 wire mesh and e-glass fibre. The surface treated SS-304 steel mesh reinforced epoxy composite gives ¾ of penetration depth from the impacting side while the other composites gives maximum penetration. Scanning electron microscopy results revealed the improved bonding of e-glass fibre and metal wire meshes with epoxy resin.

WITHDRAWN: Mechanical Strength Behaviour of Silane treated E-glass Fibre, Al-6061 and SS-304 Wire Mesh Reinforced Epoxy resin Hybrid Composites

Abstract In this research work the mechanical strength behaviour of silane treated e-glass fibre, Aluminium 6061 and stainless steel 304 metal wire mesh reinforced epoxy resin Hybrid composites were analyzed. The principal objective of this research work is to unveil the importance of silane treatment on metal surface in adhesion and delamination resistance in composites. The reinforcements were acid etched then silanated by 3-Aminopropyletrimethoxylane via aqueous solution method. The mechanical properties were found increase for surface modified reinforcements rather than as-received reinforcement epoxy composites. Maximum tensile strength, flexural strength and Izod impact energy of 134 MPa, 241 MPa and 5.4 J were observed for composite consist of surface modified SS-304 wire mesh and e-glass fibre. The surface treated SS-304 steel mesh reinforced epoxy composite gives ¾ of penetration depth from the impacting side while the other composites gives maximum penetration. Scanning electron microscopy results revealed the improved bonding of e-glass fibre and metal wire meshes with epoxy resin. These mechanically strengthened composites could be used as working material where sudden load prone zones are available. Similarly defence safety equipments, automobile body parts and construction devices manufacturing industries the requirements of these materials are highly welcome one.

Improving Mechanical Properties of Carbon/Epoxy Composite by Incorporating Functionalized Electrospun Polyacrylonitrile Nanofibers

Electrospun functionalized polyacrylonitrile grafted glycidyl methacrylate (PAN‐g‐GMA) nanofibers are incorporated between the plies of a conventional carbon fiber/epoxy composite to improve the composite's mechanical performance. Glycidyl methacrylate (GMA) is successfully grafted onto polyacrylonitrile (PAN) polymer powder via a free radical mechanism. Characterization of the electrospun PAN and PAN‐g‐GMA nanofibers indicates that the grafting of GMA does not significantly alter the tensile properties of the PAN nanofibers but results in an increase in the diameter of nanofibers. Statistical analysis of the mechanical characterization studies on PAN‐carbon/epoxy hybrid composites conclusively shows that the composite reinforced with functionalized PAN nanofibers has greater mechanical properties than that of both the neat PAN nanofiber enriched hybrid composite and control composite (without nanofibers). The improved performance is attributed to the grafted glycidyl groups on PAN, leading to stronger interactions between the nanofibers and the epoxy matrix. PAN‐g‐GMA nanofiber reinforced composite outperforms their neat PAN counterparts in tensile strength, short beam shear strength, flexural strength, and Izod impact energy absorption by 8%, 9%, 6%, and 8%, respectively. Compared to the control composite, the improvements resulting from the PAN‐g‐GMA nanofiber incorporation are even more pronounced at 28%, 41%, 32%, and 21% in the corresponding tests, respectively. image

A study of mechanical properties of biobased epoxy network: Effect of addition of epoxidized soybean oil and poly(furfuryl alcohol)

ABSTRACTA novel biobased thermoset interpenetrating network was introduced in this study. Epoxidized soybean oil (ESO) and poly(furfuryl alcohol) (PFA) were added to a commercial biobased epoxy resin. It was hypothesized that addition of ESO and PFA can decrease brittleness of bioepoxy resin and also increase biobased content. Mechanical properties of samples were evaluated using tensile and impact test. It was found that the addition of ESO and PFA increased notched Izod impact energy by 76.6%. This significant increase was related to incorporation of long flexible chains of ESO into the matrix. Hybridization of ESO and PFA in bioepoxy reduced tensile strength (around 70%), tensile modulus (around 90%), and glass transition temperature in comparison to neat bioepoxy. Tensile strength and modulus of hybridized system can be further improved by addition of natural fibers and the resultant composite may be considered as a good candidate for applications in which damping properties are important. Crosslink density was calculated using dynamic mechanical analysis and a decrease in crosslink density was observed in hybridized system. PFA domains were observed in the matrix using atomic force microscopy in peak force quantitative nano‐mechanical mode and it revealed inhomogeneity in the crosslinked structure. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44352.

Utilization of Chicken Eggshell Waste as a Bio-Filler for Thermoplastic Polymers: Thermal and Mechanical Characterization of Polypropylene Filled with Naturally Derived CaCo3

The processing and characterization of polypropylene/eggshell composites was the main objective of this study. Natural source-derived calcium carbonate (CaCO3) was extracted from waste chicken eggshell and compounded with polypropylene polymer. The compound was molded using the Extrusion Compression Molding (ECM) process. X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis were conducted on the eggshell to characterize its constituents. The effects of filler loading, 30 wt.% eggshell and 30 wt.% eggshell with 5 wt.% of maleic anhydride grafted polypropylene (MAPP) on the mechanical and thermal properties were studied. The addition of a small amount of MAPP during melt extrusion improved the dispersion and bonding of CaCO3 particles in polypropylene. 7.49% decrease in tensile strength, 35.51% enhancement in flexural modulus and 66.05% increase in notched Izod impact energy were obtained by adding 30 wt.% eggshell with 5 wt.% MAPP to polypropylene. Adding 30-wt % of eggshell filler and 5 wt.% MAPP to polypropylene delayed the flame propagation time by 99 seconds.