Molecular dynamics simulation of the influence of sizing agent on the interfacial properties of sized carbon fiber/vinyl ester resin composite modified by self-migration method

• Published in: Composite interfaces Vol. 28; no. 5; pp. 445 - 459
• Main Authors: Jiao, Weiwei, Hou, Chunli, Zhang, Xinhang, Liu, Wenbo
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 04-05-2021
• Subjects: fiber/matrix bond; interphase; Polymer-matrix composites (PMCs); transport phenomena analysis
• ISSN: 0927-6440; 1568-5543
• DOI: 10.1080/09276440.2020.1788305

The interfacial property of sized carbon fiber reinforced vinyl ester resin (SCF/VE) composite was improved by a self-migration method using acrylamide (AM) as a modifier. A molecular dynamics simulation was performed to study the influence of sizing agent on the interphase formation and the interfacial modification effect. After the system equilibrium, the analysis of monomer distribution shows that an interphase region with thickness of ~2.0-2.5 nm was formed surrounding the fiber surface and the interaction energy was increased obviously. The thickness of this interphase region is obviously larger than that of unsized carbon-reinforced composite (~0.5-1.0 nm). This is mainly due to the sizing agent diffusion to the resin and the strong polar interaction between the sizing agent and AM molecule. As a consequence, the interfacial strength and toughness of the composite were enhanced jointly, which was confirmed by the test of interface shear strength and interlaminar shear strength.