Simultaneously enhanced cryogenic tensile strength and fracture toughness of epoxy resins by carboxylic nitrile-butadiene nano-rubber

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2013-12, Vol.55, p.178-187
• Main Authors: Zhao, Yang, Chen, Zhen-Kun, Liu, Yu, Xiao, Hong-Mei, Feng, Qing-Ping, Fu, Shao-Yun
• Format: Article
• Language: English
• Subjects: A. Nano-composite; A. Polymer–matrix composites (PMCs); Applied sciences; B. Fracture toughness; B. Mechanical properties; Composites; epoxides; Exact sciences and technology; Forms of application and semi-finished materials; particles; Polymer industry, paints, wood; resins; room temperature; scanning electron microscopy; Technology of polymers; tensile strength; toluene
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2013.09.005

Epoxy resins are important matrices for composites. Carboxylic nitrile-butadiene nano-rubber (NR) particles are employed to improve the tensile strength and fracture toughness at 77K of diglycidyl ether of bisphenol-F epoxy using diethyl toluene diamine as curing agent. It is shown that the cryogenic tensile strength and fracture toughness are simultaneously enhanced by the addition of NR. Also, the fracture toughness at room temperature (RT) is enhanced by the addition of NR. On the other hand, the tensile strength at RT first increases and then decreases with further increasing the NR content up to 5phr. 5phr NR is the proper content, which corresponds to the simultaneous enhancements in the tensile strength and fracture toughness at RT. Moreover, the comparison of mechanical properties between 77K and room temperature indicates that the tensile strength, Young’s modulus and fracture toughness at 77K are higher than those at RT but the failure strain shows the opposite results. The results are properly explained by the SEM observation.