Effects of carbon nanotube/polymer interfacial bonding on the long‐term creep performance of nanophased glass fiber/epoxy composites

Abstract

This article is focused on prediction of the long‐term creep performance of glass fiber/epoxy (GE) composites reinforced with pristine carbon nanotube (CNT) and functionalized carbon nanotube (FCNT). 0.1 wt% of CNT and FCNT are added to GE composites to fabricate CNT‐GE and FCNT‐GE composite laminates, respectively. Flexural tests were carried out at room temperature (RT) and 120°C to assess the effect of environment temperature on the flexural properties of the aforesaid materials. FCNT‐GE showed highest improvement in flexural properties at RT followed by CNT‐GE composite and control GE composite, due to better stress transfer with strong chemical interfacial bonding. By using accelerated deformation at elevated temperature and time‐temperature superposition principle, long‐term creep behavior of GE, CNT‐GE, and FCNT‐GE composites at various reference temperatures (30°C, 60°C, 90°C, and 110°C) has been anticipated. Positive reinforcement efficiency is noted up to ~1010.5 and ~1012.5 years for CNT‐GE and FCNT‐GE, respectively at reference temperature of 30°C, following which it neutralized and moderately became negative. However, at higher temperature this time period is reduced abruptly due to unfavorable thermal stress generation at the CNT/polymer interface. Evaluation of thermomechanical properties were also carried out using dynamic mechanical analysis. Differential scanning calorimetry was used to investigate the variation in glass transition temperature due to CNT/FCNT addition to GE composite. Fractographic study was also carried out to know the mode of failure for CNT‐GE and FCNT‐GE composite flexural tested at room temperature.

Effects of fiber surface grafting by functionalized carbon nanotubes on the interfacial durability during cryogenic testing and conditioning of CFRP composites

“…The chemical bonding between FCNT and epoxy (ester bonds with the epoxide groups) further helps retain it's improved ILSS properties. [54][55][56] In stark contrast, neat CE composites have weak van der Waals interactions between the fiber and matrix. 57,58 Consequently, the load-carrying capacity of the composites is enhanced by improving the efficiency of load transfer across the interface in the case of FCNT-CE composite than neat CE composite.…”

Carbon nanotube/polyetheretherketone nanocomposites: mechanical, thermal, and electrical properties

“…Jia et al 122 found that the formation of CNT network structure can efficiently reduce the creep strain, for CNT/polystyrene nanocomposites. Fulmali et al 123 showed that the weak CNT-polymer bonding can cause slippage during the long-term creep behavior, based on the investigation on CNT/epoxy composites.…”

A Phenomenological Primary–Secondary–Tertiary Creep Model for Polymer-Bonded Composite Materials

“…Several studies have shown that the creep behavior of PBMs depends on many factors such as matrix content [ 6 , 7 , 8 , 9 ], particle size [ 10 , 11 , 12 ], stress [ 13 , 14 , 15 ], temperature [ 16 , 17 ], and humidity [ 18 , 19 ]. The importance of long-term properties for polymer composites are highlighted in recent studies [ 20 , 21 ].…”