Structural composites hybridized with epoxy compatible polymer/MWCNT nanofibrous interlayers

Abstract

a b s t r a c tSurface reactive P(St-co-GMA) copolymer and P(St-co-GMA)/MWCNT fibrous mats are placed onto a conventional carbon fiber/epoxy prepreg as interlayer reinforcing material. Experimental observations are used to demonstrate excellent epoxy wetting and structural compatibility of the interlayers chemically tuned for the epoxy matrix. Comparisons of increase in mechanical performance by incorporating P(Stco-GMA) and P(St-co-GMA)/MWCNT interlayers also show the contribution of MWCNT presence in the copolymer nanofibers. Flexural strength and stiffness of (0/0/0) and (90/0/90) laminates increase up to 17% when the nanocomposite interlayers are integrated. Cross-sectional SEM analyses of the failure surfaces suggest reinforcing ability of interlayers both against transverse cracking and delamination. Further examination for the delamination resistance is presented by the End Notched Flexure (ENF) tests. An improvement up to 70% in mode II strain energy release rate (G IIc ) is recorded for the laminates with nanocomposite interlayers. The resistance against transverse matrix cracking in the presence of interlayers is also elaborated. Charpy-impact and transverse-tension tests result in up to 20% and 27% increase in the impact energy absorbance and transverse tensile strength, respectively. Overall, the test results suggest that mechanical behavior of the laminates is enhanced by the nanofibrous interlayers chemicallytuned for epoxy crosslinking, with no weight penalty.

MWCNTs/P(St-co-GMA) Composite Nanofibers of Engineered Interface Chemistry for Epoxy Matrix Nanocomposites

“…The increase in stiffness on the other hand was substantially enhanced, despite the low fraction of CNT introduced into the system. On the other hand, in our relevant work as Bilge et al, 43,44 surface-reactive P(St-co-GMA) and 1% MWCNT/P(St-co-GMA) nanocomposite interlayers were introduced to the conventional carbon fiber/ epoxy prepregs by electrospinning. Use of the nanocomposite interlayers resulted in improvements in mechanical performance of composite laminates.…”

Interlayer toughening mechanisms of composite materials

“…Zucchelli et al (2011) thoroughly reviewed the available studies that have followed the traces of this novel idea and demonstrated capabilities of electrospun nanofibers as interlayers in the composite materials. Table 10.1 aims to also supplement the review with very recent studies on polymeric nanofiber toughening of composite materials (Dzenis and Reneker, 2001;Dzenis, 2008;Sihn et al, 2008;Liu et al, 2006Liu et al, , 2008Liu et al, , 2014Zucchelli et al, 2012;Magniez et al, 2011;Zhang et al, 2010Zhang et al, , 2012Bilge et al, 2012Bilge et al, , 2014Subagia et al, 2014;Li et al, 2015;Heijden et al, 2014). It is clear from the available literature that nanofiber interlayer toughening method via polymeric nanofibers is considered a promising strategy to toughen composite materials both under in-plane and out-of-plane loading conditions (Sihn et al, 2008).…”

Electrospun nanofibers as reinforcement for composite laminates materials – A review

“…An interesting reading on how these are produced and employed can be found in [118][119][120]. CNT is the structure that has been the most employed in a range of different electropsun nanofibers.In [121] the effect of adding MWCNT has been assessed performed testing P(St-co-GMA) copolymer and P(St-co-GMA)/MWCNT nanofibrous mats interleaved into carbon fiber prepregs, and comparing the results. The authors performed flexural, ENF and Charpy-impact tests do determine the effect of adding MWCNT to the P(St-co-GMA) nanofibers.…”