Effect of Electrospun Nanofibers on the Short Beam Strength of Laminated Fiberglass Composite (original) (raw)
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SHORT BEAM STRENGTH OF LAMINATED FIBERGLASS COMPOSITE WITH AND WITHOUT ELECTROSPUN TEOS NANOFIBERS
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Effect of Electrospun Fibers on the Interlaminar Properties of Woven Composites
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Journal of Reinforced Plastics and Composites, 2015
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Nylon 6,6 nanofibers manufactured by means of electrospinning have been used to interleave Mode II fracture mechanics glass and carbon unidirectional fiber composite specimens. The aim of this work was to study the effect of the nanofibers materials in their ability to reinforce the interleave. Experimental testing was carried out on specimens with a nanofibrous mat interleaved into a delaminated interface. Specimens of 10, 16 and 18 layers were manufactured and tested. Results demonstrated that the effect of nanofibers was different between the two materials and that the fiber materials play an important role in the reinforcement mechanism of the nanofibers.
Authors Figures Multimedia References Cited By Keywords Application of electrospun nanofibers for the improvements in mode-i fracture toughness of fiberglass composites Delamination is a major mode of failure in laminated composites. This paper addresses development of advanced delamination resistant composites using interlaminar SiO nanoflbers. The SiO nanoflbers were manufactured using Tetra Ethyl Orthosilicate (TEOS) sol gel. The sol gel viscosity of 100-200 cps Voltage of 18kV and distance between spinneret and grounded collector plate of 80 mm were found to be suitable for maximizing production of electrospun fibers. It was observed that typical electrospun fibers were of 300 nm diameter after they were sintered at 600 degrees C. These SiO nanoflbers produced using electrospinning were then integrated into fiber glass Epon 862 resin matrix composites. During mechanical characterization of these three phase (fiber glass+Epon 862+SiO nanoflbers) composites, extensive experimentation was carried out as per the ASTM D 5528 standard to study the influence of electrospun SiO nanoflbers on the Mode I fracture toughness of fiber glass composites. Other characterization studies were related to determining the effect of SiO nanoflbers on short beam shear strength, flexure properties, and tensile properties of three phase composites.
Electrospun nanofibers as reinforcement for composite laminates materials - A Review
Composite Structures
In the last few decades nanofibers have been developed and introduced in a vast number of industrial and research applications. One of their most effective use is as interleaved reinforcement for composite laminate materials against delamination. Nanofibrous mats have the ideal morphology to be embedded between two plies of a laminate, and a vast and deep research has been carried out investigating their effect on the global behaviour of a composite laminate. This review is the first of its kind to date which presents a detailed state-ofthe-art on the effect of nanofibrous interleaves into composite laminates with focus on the mechanical performances and behaviours of nanomodified materials. A detailed description of the working mechanisms of the nanointerleave under different load cases is presented, and a comparative analysis between papers in literature will provide readers with a powerful tool to understand and use nanofibers for reinforcing purposes.
Interlaminar toughening of glass epoxy composites by electrospun nanofibers
2016
List of publications xiii Publications directly presented in this PhD xiii Other publications xiv 1 Introduction 1.1 Fiber reinforced composites 1.2 Composite laminates and delamination 1.3 Toughening methods for FRP composites 1.3.1 Z-binders 1.3.2 Rigid nanoparticle toughened epoxies 1.3.3 Rubber and thermoplastic toughened epoxies 1.4 Nanofiber toughened composites 1.4.1 Nanofibers and their applications 1.4.2 Production of nanofibers by electrospinning 1.4.3 Nanofibers in composite materials 1.5 Objectives and outline 2 Materials and methods 2.1 Materials 2.1.1 Materials used for the production and postmodification of electrospun fibers 2.1.2 Materials used for the production of glass epoxy laminates 2.2 Electrospinning 2.2.1 Electrospinning equipment 2.2.2 Electrospun membranes 2.3 Production of glass epoxy laminates using vacuum assisted resin transfer molding 2.4 Characterization of electrospinning solutions and electrospun nanofibrous veils 2.4.1 Viscosity 2.4.2 Conductivity 2.4.3 Scanning electron microscopy 2.4.4 Tensile properties 2.4.5 Dynamic mechanical analysis 2.4.6 Infrared spectroscopy 2.5 Characterization of the composite laminates 2.5.1 Mode I interlaminar fracture toughness 2.5.2 Mode II interlaminar fracture toughness 2.5.3 Tensile properties 2.5.4 Open hole strength 2.5.5 Low velocity impact 2.5.6 Dynamic mechanical analysis 2.5.7 Optical microscopy 3 Interlaminar toughening using electrospun nanofibers: general toughening mechanisms 3.1 Introduction: a multi-level approach for analyzing nanofiber reinforced composites 3.2 Level 1: The nanotoughened epoxy 3.3 Level 2: Nanotoughened interlaminar region 3.4 Level 3: Nanotoughened laminate 3.5 Conclusions 4 Effect of electrospun morphology on the interlaminar toughness of PCL toughened laminates 4.1 Introduction: importance of toughening morphology and interlaminar crack path 4.2 Production of different electrospun morphologies and their laminates 4.3 Morphology and tensile properties of electrospun structures 4.4 Effect of the electrospun PCL morphology on the Mode I interlaminar fracture toughness 4.5 Effect of electrospun PCL morphology on the Mode II interlaminar fracture toughness 4.6 Conclusions 5 How different interleaving methods can affect the interlaminar fracture toughness 5.1 Sample preparation using different interleaving methods 5.2 Effect of the interleaving method on Mode I interlaminar fracture toughness 5.3 Position of the delamination initiation film in the DCB specimen iii 5.4 Effect of nanofiber veil areal density for SLD and DLD configuration 5.5 Effect of PCL nanofibers on the in-plane laminate properties and open hole strength 5.6 Conclusions 6 The use of triazolinedione click chemistry for tuning the mechanical properties of electrospun SBS fibers 6.1 Introduction: tunable electrospun SBS fibers 6.2 Development of an SBS electrospinning system in butyl acetate 6.3 TAD post-treatment of electrospun SBS membranes 6.4 Effect of a TAD post-treatment on the thermomechanical properties of electrospun SBS membranes 6.5 Effect of a TAD post-treatment on the tensile properties of electrospun SBS membranes 6.6 Conclusions 7 The influence of the mechanical properties of electrospun nanofibers on the interlaminar fracture toughness of nanofiber toughened laminates. 7.1 Introduction: linking the mechanical properties of tunable SBS fibers to the fracture toughness of composite laminates 7.2 Effect of MDI-TAD cross-linker on tensile properties of SBS fibers 7.3 Effect of the mechanical properties of the SBS fibers on the mechanism of electrospun fiber bridging 7.4 Effect of the mechanical properties of the SBS fibers on the Mode II interlaminar fracture toughness 7.5 Effect of the mechanical properties of the SBS fibers on the Mode I interlaminar fracture toughness 7.6 Conclusion 8 Concluding remarks and outlook References xiii
Ultra-thin electrospun nanofibers for development of damage-tolerant composite laminates
Materials Today Chemistry, 2019
The present article overcomes existing challenges ahead of inter-laminar toughening of novel multifunctional fibre-reinforced polymer composites via development and embedment of highly stretched, ultra-thin electrospun thermoplastic nanofibers made of polyamide 6.6. The nanofibers have exhibited significant enhancement of the composite laminate's structural integrity with almost zero weight penalty via ensuring a smooth stress transfer throughout the plies and serving tailoring mechanical properties in desired directions, with no interference with geometric features e.g. thickness. The findings for 1.5 grams per square meter (gsm) electrospun nanofibers have demonstrated, on test coupons specimens, improvements up to 85% and 43% in peak load and crack opening displacement, respectively, with significant improvement (> 25%) and no sacrifice of fracture toughness at both initiation and propagation phases. The initial stiffness for the modified specimens was improved by nearly 150%. The enhancement is mainly due to nano-fibres contributing to the stiffness of the resin rich area at the crack tip adjacent to the Polytetrafluoroethylene (PTFE) film. Glass fibre-reinforced woven phenolic preimpregnated composite plies have been modified with the nano-fibres (each layer having an average thickness of <1 micron) at 0.5, 1.0, 1.5, 2.0 and 4.0 gsm, electrospun at room temperature on each ply, and manufactured via autoclave vacuum bagging process. Inter-laminar fracture toughness specimens were manufactured for Mode I (double cantilever beam, DCB) fracture tests. It was found that there is threshold for electrospun nanofibers density, at which an optimum performance is reached in modified composite Manuscript File
Interlaminar shear strength (ILSS) of fiber reinforced polymer composite is an important property for most of the structural applications. Matrix modification is an effective method used to improve the interlaminar shear strength of composite. In this paper, EPON 862/w epoxy system was modified using Tetraethyl orthosilicate (TEOS) electrospun nanofibers (ENFs) which were produced using electrospinning method. Unmodified and nanofibers modified resins were used to fabricate glass fiber reinforced polymer composite (GFRP) using H-VARTM method. The ILSS of the Glass Fiber Reinforced Polymeric Composites (GFRP) was investigated. The study shows that introduction of TEOS ENFs in the epoxy resin enhanced the ILSS of GFRPby 15% with 0.6% wt. fraction of TEOS ENFs.