Interlaminar toughening of resin transfer moulded glass fibre epoxy laminates by polycaprolactone electrospun nanofibres

Abstract

Delamination and brittle matrix fracture has since long been a problem of fibre reinforced composites. This paper investigates if polycaprolactone (PCL) nanofibre nonwovens can increase the interlaminar fracture toughness of resin transfer moulded glass fibre/epoxy laminates, without causing problems during impregnation and without negatively affecting other (mechanical) properties.The mode I fracture toughness was shown to be dependent on both the nanofibre content as well as on how the nanofibres were introduced into the laminates. Almost 100% improvement in fracture toughness could be achieved by electrospinning the PCL nanofibres on both sides of the glass fibre mats prior to impregnation. This led to a mode I fracture toughness of over 1200 J/m 2 . 2Tensile and dynamic mechanical properties of the toughened laminates were not affected by the PCL nanofibres. It could be concluded that even state of the art infusion resins with a high intrinsic fracture toughness can benefit significantly from nanofibre toughening.

Electrospun nanofibers as reinforcement for composite laminates materials – A review

“…In the other 12 sets (85.7% of the total), nanofibers had positive (11 cases, 78.6% of the total) or negligible (1 case, 7.1%) effects on the performances of the samples. The highest registered improvement was 94% (UD glass fibers, PCL nanofibers, [50]). Given the larger number of papers found for carbon fibers, Figure 7 has been split in two: Figures 7a and 7b show delamination's initiation and propagation's results, respectively.…”

“…Three works in literature have been found dealing with tensile properties of nanomodified GFRP laminates, and they do not show the same agreement registered for carbon fibers. In [50] it is showed that tensile properties of UD GFRP laminates are not affected by the presence of PCL nanofiber; in [30], it is shown that PA6 nanofibers caused an increase of stress at failure of the composite of about 6% and 11% when the nanofibers were added during layup and when directly deposited onto the fabric, respectively. A unique use of Silk has been presented in [69], showing a 5% improved tensile strength.…”

Improved fatigue delamination behaviour of composite laminates with electrospun thermoplastic nanofibrous interleaves using the Central Cut-Ply method

“…Hence, many methods of interlaminar toughening have been proposed and researched over the past decades [1][2][3][4][5][6][7][8][9][10][11][12]. The more recent principle of interleaving composite laminates with electrospun nanofibrous veils has shown to be a viable interlaminar toughening method [13][14][15][16][17][18][19][20]. There are several advantages associated to these veils which adds to their commercial applicability.…”

Multiscale Polymer Composites: A Review of the Interlaminar Fracture Toughness Improvement

“…The nanocomposites thin film can also be manufactured using electrospinning [194][195][196][197] and electrospun [198][199][200] processes. These methods have gained popularity and are found to be an effective technique to also produce the electrospinning/electrospun nano-interlayers [201][202][203][204][205] which toughen the composite laminate. Klein et al [206] reported the ILFT of specimens (satin woven CFRPs) with carbon nanotube/epoxy films.…”

“…to also produce the electrospinning/electrospun nano-interlayers [201][202][203][204][205] which toughen the composite laminate. Klein et al [206] reported the ILFT of specimens (satin woven CFRPs) with carbon nanotube/epoxy films.…”