• 文献标题:   Is Graphene Always Effective in Reinforcing Composites? The Case of Highly Graphene-Modified Thermoplastic Nanofibers and Their Unfortunate Application in CFRP Laminates
  • 文献类型:   Article
  • 作  者:   MACCAFERRI E, MAZZOCCHETTI L, BENELLI T, ORTOLANI J, BRUGO TM, ZUCCHELLI A, GIORGINI L
  • 作者关键词:   polyethylene oxide, polycaprolactone, polyamide, graphene, thermal propertie, mechanical propertie, delamination, interlaminar fracture toughnes, epoxy, carbon fiber composite
  • 出版物名称:   POLYMERS
  • ISSN:  
  • 通讯作者地址:  
  • 被引频次:   1
  • DOI:   10.3390/polym14245565
  • 出版年:   2022

▎ 摘  要

Graphene (G) can effectively enhance polymers' and polymer composites' electric, thermal, and mechanical properties. Nanofibrous mats have been demonstrated to significantly increase the interlaminar fracture toughness of composite laminates, hindering delamination and, consequently, making such materials safer and more sustainable thanks to increased service life. In the present paper, poly(ethylene oxide) (PEO), polycaprolactone (PCL), and Nylon 66 nanofibers, plain or reinforced with G, were integrated into epoxy-matrix Carbon Fiber Reinforced Polymers (CFRPs) to evaluate the effect of polymers and polymers + G on the laminate mechanical properties. The main aim of this work is to compare the reinforcing action of the different nanofibers (polyether, polyester, and polyamide) and to disclose the effect of G addition. The polymers were chosen considering their thermal properties and, consequently, their mechanism of action against delamination. PEO and PCL, displaying a low melting temperature, melt, and mix during the curing cycle, act via matrix toughening; in this context, they are also used as tools to deploy G specifically in the interlaminar region when melting and mixing with epoxy resin. The high extent of modification stems from an attempt to deploy it in the interlaminar layer, thus diluting further in the resin. In contrast, Nylon 66 does not melt and maintain the nanostructure, allowing laminate toughening via nanofiber bridging. The flexural properties of the nanomodifed CFRPs were determined via a three-point bending (3PB) test, while delamination behavior in Mode I and Mode II was carried out using Double Cantilever Beam (DCB) and End-Notched Flexture (ENF) tests, respectively. The lack of a positive contribution of G in this context is an interesting point to raise in the field of nanoreinforced CFRP.